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Personality disorders disturbances of the physical brain
Medical Hypotheses 79 (2012) 487–492
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Personality disorders disturbances of the physical brain Avi Peled ⇑ Sha’ar Menashe Mental Health Center, Hadera, Israel Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa, Israel
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Article history: Received 4 June 2012 Accepted 27 June 2012
a b s t r a c t How can physical systems of the brain, explain a psychological phenomenon such as personality? Personality is an emergent property of the brain as such it requires interacting elements that generate a whole. Per definition a physical system is a compound whole made of interacting interdependent elements. The brain is composed of multiple levels of elements ranging from single neurons interconnected by axons dendrites and synapses, up to brain regions and neural network ensembles connected by multiple modalities, from direct physical pathways to synchronized functional connectivity. Today we know that the brain develops and wires according to the influences of its environment, this is called ‘‘experience dependent plasticity’’ and follows Hebbian-like algorithms. Such process ‘‘embeds’’ into the brain internal representations in the form of physical attractor configurations distributed within the brain neuralnetworks. Development entails formation of personal individual-specific network configurations found recently as resting-state networks or ‘‘default-mode networks.’’ These internal configurations represent the outer world to us and determine the way we perceive it and react to it. In other words these internal configurations determine our personality styles. The internal representations continuously adapt to the changing worlds offering good adaptability and effective functionality in our changing environments. Personality disorders are reconceptualized in terms of altered disturbed mal-developed default-modenetworks, such that the internal representations are biased, limited, fixated and non-adaptive. In this context therapy of personality disorders can be reconceptualized as experience-depended plasticity therapy. Ó 2012 Elsevier Ltd. All rights reserved.
Introduction to the physics of the brain relevant to personality How can physical systems the brain, explain a psychological phenomenon such as personality? Psychiatrists cannot avoid the psycho-physics problem; their patients suffer from psychological maladies. If psychiatrists consider themselves scientists they then acknowledge that these maladies emerge from the brain which is a physical entity. For a scientist this question can only have one answer, that of ‘‘Emergent Properties’’. Emergent Properties are characteristics of the system as a whole which are not found in its elements. ‘‘Mood’’, ‘‘consciousness’’, ‘‘awareness’’ and ‘‘identity’’ are not found in single neurons or even groups of neurons but they are properties of the brain as a whole. This materialistic explanation is not only critically necessary if we ever plan to treat the brain and cure patients; it also directs us to the prediction that mental disorders will involve the disturbances of large-scale neural networks in the brain (whole-brain disturbances). Emergence of properties requires interacting elements that generate a whole. Per definition a system is a compound whole made ⇑ Address: Sha’ar Menashe Mental Health Center, Mobile Post Hefer, 38814, Israel. Tel.: +972 522844050. E-mail addresses: [email protected], [email protected] 0306-9877/$ - see front matter Ó 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.mehy.2012.06.031
of interacting interdependent elements. The brain is composed of multiple levels of elements ranging from single neurons interconnected by axons dendrites and synapses, up to brain regions and neural network ensembles connected by multiple modalities, from direct physical pathways to synchronized functional connectivity. The networks of such interactivity can evolve in many patterns, they can be centralized, where many units (e.g., neurons or brain regions) of the system are connected to few (or one) main units (Hubs) or they can be distributed with units randomly connected forming no central organization, thus having no Hubs at all. Recently it has been found that the best organization of well functioning (optimal) systems is in-between the organizations described above; the organization is neither too centralized nor randomly dispersed, it is composed of Hubs receiving many connections from many far-away units that are a part of clusters of ‘locally’ spread highly connected nearby units. This type of organization is most effective for a well-functioning system; In the case of communication networks it is most effective for information transfer earning the title of ‘‘small world network (SWN)’’ describing effective communication transfer around the globe (Fig. 1). SWN organization entails high clustering and small path length (connections from many far-away units) comparable to random
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Fig. 1. Schematic structure of a small world network organization.
graphs. Thus in addition to small worldliness clustering coefficient, path length and hierarchy are also important measures that can be used to estimate whether a system is optimal and effective. These parameters become critical when one wants to investigate the efficacy of functioning networks and needs measurable extracted parameters to decide (or detect) whether a system is functioning optimally. How is network organization relevant to emergent properties? To answer this question we shall consider consciousness as an emergent property of the brain. According to Bernard Baars [1], consciousness emerges from global brain organizations; at each moment in time sets of partial processes integrate to form e global formation of activity. Across time the participating partial processes may change because some partial processes might be ‘‘dropped out’’ and new ones engaged in the global formation. Thus, from instant to instant the global message may change, just as conscious experience is aware of changing contents from moment to moment. Stanislav Dehene showed that the small world network organization is a relevant organization for Baar’s formulation. The Hubs of long connections from multiple clusters act as integrators of processes within the clusters, thus partial inter-cluster activity is integrated more globally at the higher level offered by the Hubs. This structure offers a multiple-level hierarchy where even higher-level integrators that have nested lower level networks can integrate even more global cognitive computations. The brain organizes accordingly with hierarchy of lower level activity integrated to form global organizations (bottom up) which in turn also influence the activity of lower level processes (topdown). Marcel Mesulam [5] described this as unimodal activity, integrating to a higher-level multimodal activity and then integrated into an even higher-level transmodal activity, that of the global all-integrating brain activity. Fuster has also described similar organization showing its relevancy to cognition and conceptual abstraction. It now becomes clear how small world optimal brain organization supports consciousness as an emerging property, and in addition it reveals how such small worldliness explains integration for perception and cognition with bottom-up and top-down dynamics maintaining global organizations in balance.
How can we now further understand conscious thought processes using this knowledge? As early as 1884 Theodor Meynert a Viennese neuropsychiatrist, stated that thoughts are represented by activated neuronal ensembles. When we have a thought, he said, it is represented by a group on acting neurons, when we have another thought it is represented by another group of activated neurons, when we have associations between these two thoughts, connections form between them. Meynert preceded his time, but today, especially with artificial
intelligence and neural network models; we can understand how neuronal ensembles actually represent information. Thus global organizations that support emergence of consciousness can be viewed as hierarchically emergent neuronal ensembles. At this point one can introduce the concept of state-space dynamics to offer a good description of the conscious thought process as a process emerging from physical complex brain systems. In state-space formulation, every neuronal activation at any given instant is a ‘‘state’’ and this state is represented as a point in a ‘‘space’’. The space represents all the other possible states of the system. As conscious experience proceeds from one occurrence to the other, and thoughts progress from one concept to the next, so the point in space ‘‘moves’’ ahead from one point to the next, creating a trajectory. Thus space-state trajectories can represent the dynamics of consciousness as the dynamics of a changing physical brain system [7]. We know that our thoughts and experiences depend on learning and practice. How is learning and acquisition of experiences accomplished within the physics of the brain? As already mentioned, as early as 1884 Meynert stated that associating information is related to the forming of connections in the brain. Donald Hebb in 1948 stated that if two (or more) neurons fire simultaneously together for certain long periods than the connection between them is strengthened. The opposite is also relevant, connections weaken if neuronal activity is not synchronous. More important is the resulting fact that when connections between two (or more) neurons are strengthened, the chance that they will fire together is increased as one activates the other (or others). Today we know that learning is a process that involves formation and strengthening of connections on a variety of scales from neurotransmitter chemical connections to structural actual synaptic connections. Once the connection within a neural ensemble is strengthened, that ensemble will tend to activate itself because of mutual activations. As such, the ensemble is a state of the system and it is represented by a point on the space (of all other states) of the system, thus the system will tend to assume that state more than other states, where neuronal connections were not strengthened. In other words the system will tend to be ‘‘drawn’’ to that state, or point in space. These dynamics of becoming drawn to a state are called ‘‘attractors’’ because the system as a whole is attracted to the state that activates it. For purposes of imagination the space of the system can now be viewed as a landscape of basins and peaks where the peaks represent the states, or activations that the system tends to avoid. In contrast the basins represent the states that the systems tend to activate and achieve [7,8,11]. This means that when we learn something new it is embedded in the physical brain in the form of attractor formations. When we recall this information the trajectory of conscious dynamic activity has reached the basin-state and activated it. This also means that in our brains we have a representation, or a ‘‘map,’’ if you will, of all of we have learned and experienced from birth until the present, in other words we are equipped with an internal representation of the world (including its psychosocial players) as we have come to know it. We can conclude that internal representations of the world which cognitively and socially guide our actions and enable us to, adapt and function in the environment, are corporal attractor configuration maps of the physical brain.
But why should learned acquired maps match the actual world, and how can such maps be achieved in a continuously changing environment? A match between environmental occurrences and the internal maps of these occurrences is intuitively explainable. If internal maps guide our reactions and behaviors in the environment, then
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in order to function in the environment we need to have an accurate representation of it. Because the environment changes continually our internal map of representations must be dynamic to adapt, learn and represent these changes. Building upon thermodynamic physics and biological evolution, Karl Friston [4] delineated a unifying theory for the brain in which he showed that the brain acts to reduce ‘‘Free Energy’’. In this case Free Energy is a measure of surprise, or in other words the statistical difference between the predictions made by the brain and the results of those predictions. The brain continually generates predictions about its input and acts to validate those predictions in a way that every change in the brain is governed by the free-energy-reduction law. The consequences are that the brain acts to achieve flexibly updated internal representations of its input. It also acts to actively develop organ senses (epithelia) and motor actions that reduce free energy by actively making input-sampling match internal predicted representations. The brain networks achieve free-energy reduction with any change of connectivity strength in order to create a hierarchy that mediates effective free energy reductions. When the brain achieves optimal reductions of free energy the cost is rooted in the connectivity values of its neural network. Optimization is ‘‘to make perfect or as effective as possible’’ and to find the best compromise among several requirements that are often conflicting. So how does the brain obtain and maintain its flexible dynamics? It can be concluded that the physical brain that obeys the natural laws of physics reduces entropy (measure of disorder) by reducing free-energy when interacting with its environment. This reduction is achieved by hierarchical network structures and motor-sensory adaptations, ultimately resulting in the formation of dynamic actively-predictive internal-representations that are actuated in the physical, ever-changing state-space configurations activated by plasticity of the physical brain of protoplasmatic neural networks. Brain systems and organizations relevant to emergence of personality disorders. Theodor Meynert, mentioned above, stated that thoughts and experiences are represented by activations of neuronal ensembles. He later postulated that each individual has unique personal experiences that characterize his/her development from infancy to adulthood. As such each individual has personal neural network activations and unique personal connectivity formations. Meynert looked for a name that would describe the individual experiencedependent personal connectivity organization of the brain and he decided to call it ‘‘EGO’’ [6]. It is customary to think that the term Ego was coined by Freud but in reality it was invented by Meynert to define a specific person-related neural-network connectivity organization of the brain, one that represents developmental experience-dependent organization of the brain. Freud was Meynert’s student and developed the idea of an Ego (detaching it from brain structure) and theoretically used it to explain clinical observations of patients’ malfunctions and complaints. The ego was conceptualized as an organizing factor mediating between drives and realty. Thus, the ego implies mechanisms such as ‘‘defense mechanisms’’ to defend ego integration from destabilizing drives. It is not within the scope of this paper to detail Freud’s work. The reader is directed to the enormous body of literature about Freud. In very concise description, one can consider Freud’s biological thinking as drives that are related to biological needs. The Ego seems to describe a developmental organization factor, and conflict-resolution and defense mechanisms seem to reflect multiple constraint activity that a neural-network-brain would require for optimization (i.e., optimization in the sense of finding the best compromise among several conflicting requirements, see above).
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Freud claimed that once neuroscience is advanced enough, then the theoretical Ego and the rest of his psychological conceptualizations would be reconceptualized as brain organization and activity within neuroscience. An important contribution of Freud’s theoretical (non-brain-related) psychological approach is the formulation of theoretical explanatory frameworks for behavioral disturbances and emotional complaints of patients and the developmental conceptualization of phases and stages. This was powerful because until then there were only a few theories about human emotional complaints; they were not comprehensive and well defined, and here for the first time a theoretical explanatory framework was described to be capable of explaining many such complaints. Furthermore the theoretical explanatory framework guided clinicians toward an idea of talking-therapy that could generate changes in the complaints and alleviate some of the ensued suffering. Those who came after Freud, elaborated on his ideas and gradually went onto develop the direction of object-relationship psychology. They began to emphasize the importance of internal representations as explanatory structures to the personality styles of people. Objects are internalized representations of experiences with important figures in the life of the individual. The ‘self’ is also an object, and it is the internal representation of the individual. The emotional experiences between the important people in one’s life and the individual, (i.e., objects and self-objects) are also internalized and represented. These representations act as a sort of internal ‘map’ that governs the way people perceive their environment including psychosocial occurrences, themselves and others. Actually it was Carl Rogers [14] who used the term ‘‘internal maps’’ for such representations and also used the term ‘‘organizmic evaluation’ to explain how these maps determine our experience, behavior and reactions. Using this conceptualization of internal objects, personality disorders could then be attributed to immature, biased and distorted internal representations. Moreover psychotherapy can then be conceptualized as the process where internal representations are ‘‘developed,’’ ‘‘maturated’’ and ‘‘corrected’’ by the psychotherapeutic technique (see below). Freud stated that in the future (his future is our present) we shall need to go back to brain-related conceptualization of his teachings. The first question that arises is – ‘‘Was Meynert correct about an individual’s network of brain organizations?’’ In recent years his network formulation was validated and is now known as the Default Mode Network. It is default because it was detected during rest, when the brain was not engaged in any cognitive task. For many years imaging studies have identified various cognitivetask-related brain networks when studied subjects were engaged in cognitive tasks in fMRI scanners. Recently subjects were investigated when daydreaming or just resting. These studies have identified a resting-state neural network organization titled default-mode-network (DMN) because it involves a default condition when cognitive task networks cease. Can this DMN constitute the Ego as was initially conceptualized by Meynert, thereafter developed theoretically by Freud, and later further elaborated upon by object relationship psychologists? In order to answer this question there must first be evidence of neural network brain organization at rest, and this has already become evident with the DMN. In addition, according to Freud the EgoDMN constitutes an organizing factor for mental function. This is evident by small worldliness; in recent years it has become evident that the DMN achieves small world organization, as such, the DMN optimizes computation organization and concords with Freud’s notion of an organizing Ego. Finally, as depicted by object-relationship psychologists, the DMN can embed information through strengthening-patterns of its connectivity formations, as previously explained. The neural network structure of the DMN can embed information and representations within its physical
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state-space attractor configuration. Based on Hebbian dynamics of learning and adjusting connectivity such internal state-space attractor maps are dynamic, and continuously adapt to the input they receive, or in other words, to environmental occurrences (psychosocial or others). Connectivity adapts to the environment by obeying the free-energy principle that reduces predicted differences between the environment and the input, thus the developing brain continuously predicts the occurrences in the environment and adapts in order to reduce surprises, and create adaptable matching (surprise-less) internal representational maps of reality. The process of internal synaptic-connectivity changes resulting from interactions with the environment is best described using the term of ExperienceDependent-Plasticity (EDP). Carhart-Harris and Friston [3] describe the connections between Ego, DMN and free-energy in a detailed all-encompassing review. Personality disorders were initially (and also currently) described as disorders of ego development and usage of primitive and ineffective defense mechanisms. With the development of object relationships, psychologists have begun to portray personality disorders in terms of immature or altered internal representations. Typically, personality disorder is defined as enduring and persistent styles of behavior and thought (about the self and others), that are inappropriate, stereotyped, maladaptive, causing distress and impairments in social and occupational functions. If internal representations (maps) are non-adaptive i.e., do not match environmental occurrences (especially psychosocial encounters), then the result would be biased, inappropriate and maladaptive thoughts and behaviors. What causes mismatching of internal representations? The answer is rooted in development; the internal representations are formed gradually during childhood/adulthood under the mechanisms of synaptic changes that obey the free-energy laws (see above). If the developmental process is delayed or hampered for some reason then the internal representational maps will be rudimental and not sufficiently complex to represent multifaceted environmental occurrences, and thus result in non-adaptive and inappropriate behaviors. Alternatively the developmental process maybe progressed but adapted to biased conditions which inevitably create biased internal representations and maps. Biased internal representations are also maladaptive and inappropriate. It is thus conceivable that those suffering from mental retardation, probably because of some neuronal tissue-defect, typically have immature, childish, non-adaptive malfunctioning personalities. Anything that hampers EDP would result in delayed immature internal configurations, probably rudimental undeveloped statespace attractor formations, causing the individual to think, react and behave as a young child that is incapable of functioning in the adult world. However sometimes the EDP and brain dynamics are intact, but the upbringing, i.e., the psychosocial context within which one develops is biased in specific aspects. These specific experiential distortions will be embedded as misrepresentations or partial circumscribed biases and deformations within the internal map of object representations. Normally (statistically) everyone encounters similar histories of psychosocial contexts from infancy through childhood and to adulthood. Generally speaking infancy is characterized by a structured family care-giving environment where the individual is relatively passive and surprises and frustrations are reduced by parental care-giving efforts. These first relatively stable and comfortable conditions are essential for the development of initial stable internal configurations. Neural-network structures are probably just beginning to transform from relatively random activity to better structured initial state-space configurations expressed as primordial attractor mapping. The structured routine of infant care-giving is directly relevant to the formation of
hebbian ensembles, as these require repeated coherent activations of neuronal ensembles to form the basic attractor state-space configurations. Progressing to childhood, each individual encounters more complicated and less caring environments. It is inevitable that going to kindergarten and then to school, leaving the protective environment of the home and family, will result in more complex unpredictable (surprising) and frustrating environments that multiply with progression to adulthood. The rudimentary unstable initial configuration maps now gradually begin to incorporate more complex occurrences including representations that involve frustrations surprises and delay predictions, and thus acquire flexibility that is necessary for optimal adaptability and matching dynamics with the environment. A biased psychosocial context can begin as early as the first phases of development. For example if the mother’s, attitude toward the infant child is somewhat (statistically) biased, e.g., an over-admiring parent can generate in the child’s internal selfrepresentations inflated self-esteem. If the parent is overprotective, and reduces surprises and eliminates frustrations, the child will not learn to cope with unpredictable conditions and the child might be deprived of internal representations that would later help him cope and adapt to disappointing, frustrating surprises in the environment. We shall see how inadaptability and mismatch results in the emergent property of reduced anxious mood, something that characterizes complaints of individuals with personality disorders [9,10,12]. The above example is restricted to a specific circumscribed bias in the developmental psychosocial context. What happens if multiple biases, such as a vastly unstable family with unstable everchanging attitudes toward the infant? In this case the transition from a rudimentary fragmented, unstable internally-represented configuration, toward a mature coherent and complex map of internal constructs, can be hampered. This leaves the individual with rudimentary fragmented, unstable internal-representations leading him to experience the world as unstable, split and frustrating. Such fragmented, unstable internal representations will mismatch and become non-adaptive to psychosocial contexts and occurrences in the environment. They might become severe and have the potential to fragment experiences altogether resulting in psychosis. These cases are typically titled ‘‘Borderline’’ personality disorders (on the border of psychosis). Severe pathological development of internal representations results in emergent properties of markedly unstable mood and even psychosis that are typical clinical manifestations [12]. To conclude, it is possible to re-conceptualize personality disorders in terms of altered disturbed mal-developed DMN organization. Thus the psychological formulation is explained in terms of the physical brain which by EDP and free-energy principle creates biased immature personality-related internal representations (or altered object relationships).
Testable predictions about treating the physical brain of personality disorders As explained above, personality disorders are reconceptualized in terms of altered disturbed mal-developed DMN. Based on this assumption therapy for personality disorders should involve reexperiences (i.e., therapeutic sessions) in which maladaptive experiences are suppressed by more adaptive maturing experiences from the therapeutic interrelationships with a professional psychotherapist. Accordingly sets of connectivity patterns from the maladaptive internal organizations are gradually substituted by more adaptive mature structures. According to this description one can understand how personality disorders can be treated by
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psychotherapy offering an EDP process to make internal representations more mature and effectively adaptive, i.e., turning the internal representations into optimal SWN similar to that of healthy subjects that have no personality disorder. Thus maturated, better matching and adaptive internal representations have less deoptimization dynamics (see above) and better adaptability explaining how the signs, symptoms and other manifestations of personality disorders can be reduced and even eliminated (cured). The descriptions of current therapies in terms of their relevance to neural-network organization of the brain reveal something that could not be appreciated without brain-related conceptualizations that reveal the potential of combining the different interventions. The effects of psychotherapy depend on connectivity dynamics and such dynamics are facilitated by plasticity-inducing medication, thus it is expected that synaptogenetic medication will enhance psychotherapeutic effects. The induction of plasticity for adult psychotherapy is so powerful that it can be compared to the pliable brain plasticity of a small child. We know that early in development the child’s brain is very ‘‘plastic’’ and offers amazing learning capabilities; these have a window of opportunity and as the child becomes adult the ‘‘plasticity-window’’ closes and things that were possible in childhood are no longer feasible. There are many examples, for instance learning a new language with its corresponding accent can be achieved only early in childhood. But even more important the amazing plasticity of the child’s brain enables education i.e., the necessary experience for maturation of well-adaptive constructs of internal representations, such as mature well-developed optimal DMS (or ego if you will). Now imagine the enormous potential of correcting mal-educated non-adaptive internal-configurations if the patient’s brain can be ‘‘pulled-back’’ in time, and induction of plasticity can ‘‘bring’’ the brain back in time to have the capability of the child’s brain. Think of a plasticity-induced time-window for correction and what a powerful tool can that become. It is important to remember that if a powerful medicationinduced plasticity-window can be achieved our experiencedependent interventions (i.e., the various types of psychotherapies, from dynamic, to cognitive and supportive) must become more organized and better directed to targets specifically identified (diagnosed) in the mal-developed DMN and its SWN internal configurations. The first step would be to recognize that all psychotherapies are aspects or versions of EDP-therapy, in fact switching from terminology which is not-brain-related to that which is related to the brain, then changing the title of ‘‘Psychotherapy’’ to EDP-therapy is advantageous and neuroscientifically more informative. Two modes are available to try and classify the various types of psychotherapy under the framework of EDP-therapy. One directed to targeting a specific result, i.e., one of improving brain organization, and the other based upon the psychotherapy technique (supportive, cognitive, or dynamic insight-oriented). Here targeting improved brain organization is chosen, but as typically turns out, there is substantial correlation between techniques and therapeutic targets. Targets for improved brain organization can roughly be divided into two; first a general developmental target to globally advance, mature and optimize the internal representations; second, specific function-related targeted interventions directed to improve specific distorted maladaptive representations which are critically involved in limited areas of function and perception. These circumscribed targets can generally be defined as ‘‘sensitivity’’ of personality to specific situations or occurrences. These two orientations also have different levels. The superficial level involves straight-forward consciousness (global brain organizations, see Bernard Baars above) requires psychotherapy intervention along the lines of cognitive behavioral therapy, and similar techniques including interventions that are related to psychodrama
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and art therapy. At this level targeting more circumscribed targets such as desensitization techniques in phobias, are appropriate. The more complicated level involves internal representations structurally incorporated in the brain connectivity configurations are unconscious because they do not always participate in global organizations (see above). At this level insight oriented psychodynamic techniques are effective. These are typically relevant to circumscribed issues of self-esteem, and sensitivities to criticism (narcissistic personality disorders). General global maturating therapy for undeveloped internal representations and DMNs can entail the general mother–child transference model and the psychological ‘‘re-growing’’ dynamics for developing a more mature personality. It is evident, from the above description, that the different psychotherapies developed over the years, are not to be abandoned, but rather re-conceptualized as EDP-therapies. They can now become developed toward diagnosable disturbances within the maps of internal configurations and different pathologies of DMN organizations. Furthermore they need to be coupled with medication-induced plasticity time-windows that enable powerful corrective-changes of brain organization.
Verification of plasticity inducing corrective therapies for personality disorders, There is an increasing body of evidence pointing to a relationship between personality and brain markers. Wei et al. [16] studied associations between personality dimensions of extraversion and neuroticism and the local synchronization of spontaneous blood oxygen level-dependent activity assessed by regional homogeneity approach. Their results revealed the significant negative correlation between neuroticism and regional homogeneity in the left middle frontal gyrus, providing evidence for the left frontal activation involved in pleasant emotion. Regional homogeneity was correlated negatively with extraversion in the medial prefrontal cortex, an important portion of the default mode network, thus further indicating the relationship between DMN and personality. In addition, regional homogeneity in the insula, cerebellum and cingulate gyrus was correlated positively with extraversion, suggesting the associations between individual difference in extraversion and specific brain regions involved in affective processing. These findings shed light on the important relationship between the synchronization of spontaneous fluctuations and personality dimensions of extraversion and neuroticism, which provide further evidence for the neural underpinning of individual difference in personality traits. A quantitative meta-analysis that included 87 studies, representing 1433 participants, was conducted by Qin and Northoff [13] to discuss the relationship between the self and resting state activity, as reflected by the default-mode network. Results suggest that our sense of self may result from a specific kind of interaction between resting state activity and stimulus-induced activity, i.e., rest-stimulus interaction, within the midline brain regions. Volkow et al. [15] uncovered an association between positive emotionality and baseline metabolism in regions from the DMN, which suggests that positive emotionality may relate to global cortical processes that are active during resting conditions. Several functional neuroimaging studies have reported regionally abnormal activation of the frontal cortex in individuals with borderline personality disorder. Wolf et al. [17] found within a network comprising cortical midline regions (‘‘default mode network’’), patients with borderline personality disorder showed an increase in functional connectivity in the left frontopolar cortex and the left insula, whereas decreased connectivity was found in the left cuneus. Within a network comprising predominantly right lateral prefrontal and bilateral parietal regions, patients with
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borderline personality disorder showed decreased connectivity of the left inferior parietal lobule and the right middle temporal cortex compared with healthy controls. They found correlations between functional connectivity of the frontopolar cortex and measures of impulsivity as well as between connectivity of the insula/cuneus and dissociation tension. Their data suggest that abnormal functional connectivity of temporally coherent restingstate networks may underlie certain symptom clusters in patients with borderline personality disorders. These studies propose the initial possible methodologies that will one day offer a good assessment of the default mode network alterations in personality disordered patients. These same methods will help reveal psychotherapy-related plasticity changes. The field of investigating alterations in brain activity due to psychotherapy is still to be developed however there are initial attempts at this type of investigation for example Berkovich-Ohana et al. [2] show that the DMN can be studied non-invasively by EEG. DMN deactivation was identified during the transition from resting state to a time production task, as lower gamma (25–45 Hz) power over frontal and midline regions. They show that mindfulness meditation practitioners exhibited a trait lower frontal gamma activity, related to narrative self-reference and DMN activity; this is interpreted as mindfulness meditation induces neuroplasticity practice in self-referential from the early stages. If mindfulness meditation can be described as similar in some aspects to insight-inducing psychotherapy as a way to study brain correlates of psychotherapy is possible.
Conflict of interest statement None declared.
References [1] Baars BB. A Cognitive Theory of Consciousness. New York: Oxford University Press; 1988. [2] Berkovich-Ohana A, Glicksohn J, Goldstein A. Mindfulness-induced changes in gamma band activity – implications for the default mode network, selfreference and attention. Clin Neurophysiol 2012;123(4):700–10. [3] Carhart-Harris RL, Friston KJ. The default-mode, ego-functions and freeenergy: a neurobiological account of Freudian ideas. Brain 2010;133(4):1265–83. [4] Friston K, Klass ES. Free-energy and the brain. Synthese 2007;159:417–58. [5] Mesulam M. From sensation to cognition. Brain 1998;121:1013–52. [6] Meynert T, Psychiatry; A clinical treaties on diseases of the for-brain. Translated by B. Sachs Ney York and London G.P. Putnam’s Sons; 1884. [7] Peled A, Geva AB. Brain organization and psychodynamics. J Psychother Pract Res 1999;8(1):24–39. [8] Peled A. From plasticity to complexity. A new diagnostic method for psychiatry. Med Hypotheses 2004;63(1):110–4. [9] Peled A. Plasticity imbalance in mental disorders the neuroscience of psychiatry: implications for diagnosis and research. Med Hypotheses 2005;65(5):947–52. [10] Peled A. Brain profiling and clinical neuroscience. Med hypotheses 2006;67:941–6. [11] Peled A. Neuroscientific psychiatric diagnoses. Med hypotheses 2009;73:220–9. [12] Peled A. NeuroAnalysis: a method for brain-related neuroscientific diagnosis of mental disorders. Med Hypotheses 2012;78(5):636–40. [13] Qin P, Northoff G. How is our self related to midline regions and the defaultmode network? Neuroimage 2011;57(3):1221–33. [14] Rogers CR. Client Centered Therapy, its Current Practice Implications and Theory. Boston: Houghton Mifflin Company Boston; 1965. [15] Volkow ND, Tomasi D, Wang GJ, Fowler JS, Telang F, Goldstein RZ, et al. Positive emotionality is associated with baseline metabolism in orbitofrontal cortex and in regions of the default network. Mol Psychiatry 2011;16(8):818–25. http://dx.doi.org/10.1038/mp. 2011.30. [16] Wei L, Duan X, Yang Y, Liao W, Gao Q, Ding JR, et al. The synchronization of spontaneous BOLD activity predicts extraversion and neuroticism. Brain Res 2011;24(1419):68–75. [17] Wolf RC, Sambataro F, Vasic N, Schmid M, Thomann PA, Bienentreu SD, et al. Aberrant connectivity of resting-state networks in borderline personality disorder. J Psychiatry Neurosci 2011;36(6):402–11.
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Medical Hypotheses journal homepage: www.elsevier.com/locate/mehy
Personality disorders disturbances of the physical brain Avi Peled ⇑ Sha’ar Menashe Mental Health Center, Hadera, Israel Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa, Israel
a r t i c l e
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Article history: Received 4 June 2012 Accepted 27 June 2012
a b s t r a c t How can physical systems of the brain, explain a psychological phenomenon such as personality? Personality is an emergent property of the brain as such it requires interacting elements that generate a whole. Per definition a physical system is a compound whole made of interacting interdependent elements. The brain is composed of multiple levels of elements ranging from single neurons interconnected by axons dendrites and synapses, up to brain regions and neural network ensembles connected by multiple modalities, from direct physical pathways to synchronized functional connectivity. Today we know that the brain develops and wires according to the influences of its environment, this is called ‘‘experience dependent plasticity’’ and follows Hebbian-like algorithms. Such process ‘‘embeds’’ into the brain internal representations in the form of physical attractor configurations distributed within the brain neuralnetworks. Development entails formation of personal individual-specific network configurations found recently as resting-state networks or ‘‘default-mode networks.’’ These internal configurations represent the outer world to us and determine the way we perceive it and react to it. In other words these internal configurations determine our personality styles. The internal representations continuously adapt to the changing worlds offering good adaptability and effective functionality in our changing environments. Personality disorders are reconceptualized in terms of altered disturbed mal-developed default-modenetworks, such that the internal representations are biased, limited, fixated and non-adaptive. In this context therapy of personality disorders can be reconceptualized as experience-depended plasticity therapy. Ó 2012 Elsevier Ltd. All rights reserved.
Introduction to the physics of the brain relevant to personality How can physical systems the brain, explain a psychological phenomenon such as personality? Psychiatrists cannot avoid the psycho-physics problem; their patients suffer from psychological maladies. If psychiatrists consider themselves scientists they then acknowledge that these maladies emerge from the brain which is a physical entity. For a scientist this question can only have one answer, that of ‘‘Emergent Properties’’. Emergent Properties are characteristics of the system as a whole which are not found in its elements. ‘‘Mood’’, ‘‘consciousness’’, ‘‘awareness’’ and ‘‘identity’’ are not found in single neurons or even groups of neurons but they are properties of the brain as a whole. This materialistic explanation is not only critically necessary if we ever plan to treat the brain and cure patients; it also directs us to the prediction that mental disorders will involve the disturbances of large-scale neural networks in the brain (whole-brain disturbances). Emergence of properties requires interacting elements that generate a whole. Per definition a system is a compound whole made ⇑ Address: Sha’ar Menashe Mental Health Center, Mobile Post Hefer, 38814, Israel. Tel.: +972 522844050. E-mail addresses: [email protected], [email protected] 0306-9877/$ - see front matter Ó 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.mehy.2012.06.031
of interacting interdependent elements. The brain is composed of multiple levels of elements ranging from single neurons interconnected by axons dendrites and synapses, up to brain regions and neural network ensembles connected by multiple modalities, from direct physical pathways to synchronized functional connectivity. The networks of such interactivity can evolve in many patterns, they can be centralized, where many units (e.g., neurons or brain regions) of the system are connected to few (or one) main units (Hubs) or they can be distributed with units randomly connected forming no central organization, thus having no Hubs at all. Recently it has been found that the best organization of well functioning (optimal) systems is in-between the organizations described above; the organization is neither too centralized nor randomly dispersed, it is composed of Hubs receiving many connections from many far-away units that are a part of clusters of ‘locally’ spread highly connected nearby units. This type of organization is most effective for a well-functioning system; In the case of communication networks it is most effective for information transfer earning the title of ‘‘small world network (SWN)’’ describing effective communication transfer around the globe (Fig. 1). SWN organization entails high clustering and small path length (connections from many far-away units) comparable to random
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Fig. 1. Schematic structure of a small world network organization.
graphs. Thus in addition to small worldliness clustering coefficient, path length and hierarchy are also important measures that can be used to estimate whether a system is optimal and effective. These parameters become critical when one wants to investigate the efficacy of functioning networks and needs measurable extracted parameters to decide (or detect) whether a system is functioning optimally. How is network organization relevant to emergent properties? To answer this question we shall consider consciousness as an emergent property of the brain. According to Bernard Baars [1], consciousness emerges from global brain organizations; at each moment in time sets of partial processes integrate to form e global formation of activity. Across time the participating partial processes may change because some partial processes might be ‘‘dropped out’’ and new ones engaged in the global formation. Thus, from instant to instant the global message may change, just as conscious experience is aware of changing contents from moment to moment. Stanislav Dehene showed that the small world network organization is a relevant organization for Baar’s formulation. The Hubs of long connections from multiple clusters act as integrators of processes within the clusters, thus partial inter-cluster activity is integrated more globally at the higher level offered by the Hubs. This structure offers a multiple-level hierarchy where even higher-level integrators that have nested lower level networks can integrate even more global cognitive computations. The brain organizes accordingly with hierarchy of lower level activity integrated to form global organizations (bottom up) which in turn also influence the activity of lower level processes (topdown). Marcel Mesulam [5] described this as unimodal activity, integrating to a higher-level multimodal activity and then integrated into an even higher-level transmodal activity, that of the global all-integrating brain activity. Fuster has also described similar organization showing its relevancy to cognition and conceptual abstraction. It now becomes clear how small world optimal brain organization supports consciousness as an emerging property, and in addition it reveals how such small worldliness explains integration for perception and cognition with bottom-up and top-down dynamics maintaining global organizations in balance.
How can we now further understand conscious thought processes using this knowledge? As early as 1884 Theodor Meynert a Viennese neuropsychiatrist, stated that thoughts are represented by activated neuronal ensembles. When we have a thought, he said, it is represented by a group on acting neurons, when we have another thought it is represented by another group of activated neurons, when we have associations between these two thoughts, connections form between them. Meynert preceded his time, but today, especially with artificial
intelligence and neural network models; we can understand how neuronal ensembles actually represent information. Thus global organizations that support emergence of consciousness can be viewed as hierarchically emergent neuronal ensembles. At this point one can introduce the concept of state-space dynamics to offer a good description of the conscious thought process as a process emerging from physical complex brain systems. In state-space formulation, every neuronal activation at any given instant is a ‘‘state’’ and this state is represented as a point in a ‘‘space’’. The space represents all the other possible states of the system. As conscious experience proceeds from one occurrence to the other, and thoughts progress from one concept to the next, so the point in space ‘‘moves’’ ahead from one point to the next, creating a trajectory. Thus space-state trajectories can represent the dynamics of consciousness as the dynamics of a changing physical brain system [7]. We know that our thoughts and experiences depend on learning and practice. How is learning and acquisition of experiences accomplished within the physics of the brain? As already mentioned, as early as 1884 Meynert stated that associating information is related to the forming of connections in the brain. Donald Hebb in 1948 stated that if two (or more) neurons fire simultaneously together for certain long periods than the connection between them is strengthened. The opposite is also relevant, connections weaken if neuronal activity is not synchronous. More important is the resulting fact that when connections between two (or more) neurons are strengthened, the chance that they will fire together is increased as one activates the other (or others). Today we know that learning is a process that involves formation and strengthening of connections on a variety of scales from neurotransmitter chemical connections to structural actual synaptic connections. Once the connection within a neural ensemble is strengthened, that ensemble will tend to activate itself because of mutual activations. As such, the ensemble is a state of the system and it is represented by a point on the space (of all other states) of the system, thus the system will tend to assume that state more than other states, where neuronal connections were not strengthened. In other words the system will tend to be ‘‘drawn’’ to that state, or point in space. These dynamics of becoming drawn to a state are called ‘‘attractors’’ because the system as a whole is attracted to the state that activates it. For purposes of imagination the space of the system can now be viewed as a landscape of basins and peaks where the peaks represent the states, or activations that the system tends to avoid. In contrast the basins represent the states that the systems tend to activate and achieve [7,8,11]. This means that when we learn something new it is embedded in the physical brain in the form of attractor formations. When we recall this information the trajectory of conscious dynamic activity has reached the basin-state and activated it. This also means that in our brains we have a representation, or a ‘‘map,’’ if you will, of all of we have learned and experienced from birth until the present, in other words we are equipped with an internal representation of the world (including its psychosocial players) as we have come to know it. We can conclude that internal representations of the world which cognitively and socially guide our actions and enable us to, adapt and function in the environment, are corporal attractor configuration maps of the physical brain.
But why should learned acquired maps match the actual world, and how can such maps be achieved in a continuously changing environment? A match between environmental occurrences and the internal maps of these occurrences is intuitively explainable. If internal maps guide our reactions and behaviors in the environment, then
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in order to function in the environment we need to have an accurate representation of it. Because the environment changes continually our internal map of representations must be dynamic to adapt, learn and represent these changes. Building upon thermodynamic physics and biological evolution, Karl Friston [4] delineated a unifying theory for the brain in which he showed that the brain acts to reduce ‘‘Free Energy’’. In this case Free Energy is a measure of surprise, or in other words the statistical difference between the predictions made by the brain and the results of those predictions. The brain continually generates predictions about its input and acts to validate those predictions in a way that every change in the brain is governed by the free-energy-reduction law. The consequences are that the brain acts to achieve flexibly updated internal representations of its input. It also acts to actively develop organ senses (epithelia) and motor actions that reduce free energy by actively making input-sampling match internal predicted representations. The brain networks achieve free-energy reduction with any change of connectivity strength in order to create a hierarchy that mediates effective free energy reductions. When the brain achieves optimal reductions of free energy the cost is rooted in the connectivity values of its neural network. Optimization is ‘‘to make perfect or as effective as possible’’ and to find the best compromise among several requirements that are often conflicting. So how does the brain obtain and maintain its flexible dynamics? It can be concluded that the physical brain that obeys the natural laws of physics reduces entropy (measure of disorder) by reducing free-energy when interacting with its environment. This reduction is achieved by hierarchical network structures and motor-sensory adaptations, ultimately resulting in the formation of dynamic actively-predictive internal-representations that are actuated in the physical, ever-changing state-space configurations activated by plasticity of the physical brain of protoplasmatic neural networks. Brain systems and organizations relevant to emergence of personality disorders. Theodor Meynert, mentioned above, stated that thoughts and experiences are represented by activations of neuronal ensembles. He later postulated that each individual has unique personal experiences that characterize his/her development from infancy to adulthood. As such each individual has personal neural network activations and unique personal connectivity formations. Meynert looked for a name that would describe the individual experiencedependent personal connectivity organization of the brain and he decided to call it ‘‘EGO’’ [6]. It is customary to think that the term Ego was coined by Freud but in reality it was invented by Meynert to define a specific person-related neural-network connectivity organization of the brain, one that represents developmental experience-dependent organization of the brain. Freud was Meynert’s student and developed the idea of an Ego (detaching it from brain structure) and theoretically used it to explain clinical observations of patients’ malfunctions and complaints. The ego was conceptualized as an organizing factor mediating between drives and realty. Thus, the ego implies mechanisms such as ‘‘defense mechanisms’’ to defend ego integration from destabilizing drives. It is not within the scope of this paper to detail Freud’s work. The reader is directed to the enormous body of literature about Freud. In very concise description, one can consider Freud’s biological thinking as drives that are related to biological needs. The Ego seems to describe a developmental organization factor, and conflict-resolution and defense mechanisms seem to reflect multiple constraint activity that a neural-network-brain would require for optimization (i.e., optimization in the sense of finding the best compromise among several conflicting requirements, see above).
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Freud claimed that once neuroscience is advanced enough, then the theoretical Ego and the rest of his psychological conceptualizations would be reconceptualized as brain organization and activity within neuroscience. An important contribution of Freud’s theoretical (non-brain-related) psychological approach is the formulation of theoretical explanatory frameworks for behavioral disturbances and emotional complaints of patients and the developmental conceptualization of phases and stages. This was powerful because until then there were only a few theories about human emotional complaints; they were not comprehensive and well defined, and here for the first time a theoretical explanatory framework was described to be capable of explaining many such complaints. Furthermore the theoretical explanatory framework guided clinicians toward an idea of talking-therapy that could generate changes in the complaints and alleviate some of the ensued suffering. Those who came after Freud, elaborated on his ideas and gradually went onto develop the direction of object-relationship psychology. They began to emphasize the importance of internal representations as explanatory structures to the personality styles of people. Objects are internalized representations of experiences with important figures in the life of the individual. The ‘self’ is also an object, and it is the internal representation of the individual. The emotional experiences between the important people in one’s life and the individual, (i.e., objects and self-objects) are also internalized and represented. These representations act as a sort of internal ‘map’ that governs the way people perceive their environment including psychosocial occurrences, themselves and others. Actually it was Carl Rogers [14] who used the term ‘‘internal maps’’ for such representations and also used the term ‘‘organizmic evaluation’ to explain how these maps determine our experience, behavior and reactions. Using this conceptualization of internal objects, personality disorders could then be attributed to immature, biased and distorted internal representations. Moreover psychotherapy can then be conceptualized as the process where internal representations are ‘‘developed,’’ ‘‘maturated’’ and ‘‘corrected’’ by the psychotherapeutic technique (see below). Freud stated that in the future (his future is our present) we shall need to go back to brain-related conceptualization of his teachings. The first question that arises is – ‘‘Was Meynert correct about an individual’s network of brain organizations?’’ In recent years his network formulation was validated and is now known as the Default Mode Network. It is default because it was detected during rest, when the brain was not engaged in any cognitive task. For many years imaging studies have identified various cognitivetask-related brain networks when studied subjects were engaged in cognitive tasks in fMRI scanners. Recently subjects were investigated when daydreaming or just resting. These studies have identified a resting-state neural network organization titled default-mode-network (DMN) because it involves a default condition when cognitive task networks cease. Can this DMN constitute the Ego as was initially conceptualized by Meynert, thereafter developed theoretically by Freud, and later further elaborated upon by object relationship psychologists? In order to answer this question there must first be evidence of neural network brain organization at rest, and this has already become evident with the DMN. In addition, according to Freud the EgoDMN constitutes an organizing factor for mental function. This is evident by small worldliness; in recent years it has become evident that the DMN achieves small world organization, as such, the DMN optimizes computation organization and concords with Freud’s notion of an organizing Ego. Finally, as depicted by object-relationship psychologists, the DMN can embed information through strengthening-patterns of its connectivity formations, as previously explained. The neural network structure of the DMN can embed information and representations within its physical
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state-space attractor configuration. Based on Hebbian dynamics of learning and adjusting connectivity such internal state-space attractor maps are dynamic, and continuously adapt to the input they receive, or in other words, to environmental occurrences (psychosocial or others). Connectivity adapts to the environment by obeying the free-energy principle that reduces predicted differences between the environment and the input, thus the developing brain continuously predicts the occurrences in the environment and adapts in order to reduce surprises, and create adaptable matching (surprise-less) internal representational maps of reality. The process of internal synaptic-connectivity changes resulting from interactions with the environment is best described using the term of ExperienceDependent-Plasticity (EDP). Carhart-Harris and Friston [3] describe the connections between Ego, DMN and free-energy in a detailed all-encompassing review. Personality disorders were initially (and also currently) described as disorders of ego development and usage of primitive and ineffective defense mechanisms. With the development of object relationships, psychologists have begun to portray personality disorders in terms of immature or altered internal representations. Typically, personality disorder is defined as enduring and persistent styles of behavior and thought (about the self and others), that are inappropriate, stereotyped, maladaptive, causing distress and impairments in social and occupational functions. If internal representations (maps) are non-adaptive i.e., do not match environmental occurrences (especially psychosocial encounters), then the result would be biased, inappropriate and maladaptive thoughts and behaviors. What causes mismatching of internal representations? The answer is rooted in development; the internal representations are formed gradually during childhood/adulthood under the mechanisms of synaptic changes that obey the free-energy laws (see above). If the developmental process is delayed or hampered for some reason then the internal representational maps will be rudimental and not sufficiently complex to represent multifaceted environmental occurrences, and thus result in non-adaptive and inappropriate behaviors. Alternatively the developmental process maybe progressed but adapted to biased conditions which inevitably create biased internal representations and maps. Biased internal representations are also maladaptive and inappropriate. It is thus conceivable that those suffering from mental retardation, probably because of some neuronal tissue-defect, typically have immature, childish, non-adaptive malfunctioning personalities. Anything that hampers EDP would result in delayed immature internal configurations, probably rudimental undeveloped statespace attractor formations, causing the individual to think, react and behave as a young child that is incapable of functioning in the adult world. However sometimes the EDP and brain dynamics are intact, but the upbringing, i.e., the psychosocial context within which one develops is biased in specific aspects. These specific experiential distortions will be embedded as misrepresentations or partial circumscribed biases and deformations within the internal map of object representations. Normally (statistically) everyone encounters similar histories of psychosocial contexts from infancy through childhood and to adulthood. Generally speaking infancy is characterized by a structured family care-giving environment where the individual is relatively passive and surprises and frustrations are reduced by parental care-giving efforts. These first relatively stable and comfortable conditions are essential for the development of initial stable internal configurations. Neural-network structures are probably just beginning to transform from relatively random activity to better structured initial state-space configurations expressed as primordial attractor mapping. The structured routine of infant care-giving is directly relevant to the formation of
hebbian ensembles, as these require repeated coherent activations of neuronal ensembles to form the basic attractor state-space configurations. Progressing to childhood, each individual encounters more complicated and less caring environments. It is inevitable that going to kindergarten and then to school, leaving the protective environment of the home and family, will result in more complex unpredictable (surprising) and frustrating environments that multiply with progression to adulthood. The rudimentary unstable initial configuration maps now gradually begin to incorporate more complex occurrences including representations that involve frustrations surprises and delay predictions, and thus acquire flexibility that is necessary for optimal adaptability and matching dynamics with the environment. A biased psychosocial context can begin as early as the first phases of development. For example if the mother’s, attitude toward the infant child is somewhat (statistically) biased, e.g., an over-admiring parent can generate in the child’s internal selfrepresentations inflated self-esteem. If the parent is overprotective, and reduces surprises and eliminates frustrations, the child will not learn to cope with unpredictable conditions and the child might be deprived of internal representations that would later help him cope and adapt to disappointing, frustrating surprises in the environment. We shall see how inadaptability and mismatch results in the emergent property of reduced anxious mood, something that characterizes complaints of individuals with personality disorders [9,10,12]. The above example is restricted to a specific circumscribed bias in the developmental psychosocial context. What happens if multiple biases, such as a vastly unstable family with unstable everchanging attitudes toward the infant? In this case the transition from a rudimentary fragmented, unstable internally-represented configuration, toward a mature coherent and complex map of internal constructs, can be hampered. This leaves the individual with rudimentary fragmented, unstable internal-representations leading him to experience the world as unstable, split and frustrating. Such fragmented, unstable internal representations will mismatch and become non-adaptive to psychosocial contexts and occurrences in the environment. They might become severe and have the potential to fragment experiences altogether resulting in psychosis. These cases are typically titled ‘‘Borderline’’ personality disorders (on the border of psychosis). Severe pathological development of internal representations results in emergent properties of markedly unstable mood and even psychosis that are typical clinical manifestations [12]. To conclude, it is possible to re-conceptualize personality disorders in terms of altered disturbed mal-developed DMN organization. Thus the psychological formulation is explained in terms of the physical brain which by EDP and free-energy principle creates biased immature personality-related internal representations (or altered object relationships).
Testable predictions about treating the physical brain of personality disorders As explained above, personality disorders are reconceptualized in terms of altered disturbed mal-developed DMN. Based on this assumption therapy for personality disorders should involve reexperiences (i.e., therapeutic sessions) in which maladaptive experiences are suppressed by more adaptive maturing experiences from the therapeutic interrelationships with a professional psychotherapist. Accordingly sets of connectivity patterns from the maladaptive internal organizations are gradually substituted by more adaptive mature structures. According to this description one can understand how personality disorders can be treated by
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psychotherapy offering an EDP process to make internal representations more mature and effectively adaptive, i.e., turning the internal representations into optimal SWN similar to that of healthy subjects that have no personality disorder. Thus maturated, better matching and adaptive internal representations have less deoptimization dynamics (see above) and better adaptability explaining how the signs, symptoms and other manifestations of personality disorders can be reduced and even eliminated (cured). The descriptions of current therapies in terms of their relevance to neural-network organization of the brain reveal something that could not be appreciated without brain-related conceptualizations that reveal the potential of combining the different interventions. The effects of psychotherapy depend on connectivity dynamics and such dynamics are facilitated by plasticity-inducing medication, thus it is expected that synaptogenetic medication will enhance psychotherapeutic effects. The induction of plasticity for adult psychotherapy is so powerful that it can be compared to the pliable brain plasticity of a small child. We know that early in development the child’s brain is very ‘‘plastic’’ and offers amazing learning capabilities; these have a window of opportunity and as the child becomes adult the ‘‘plasticity-window’’ closes and things that were possible in childhood are no longer feasible. There are many examples, for instance learning a new language with its corresponding accent can be achieved only early in childhood. But even more important the amazing plasticity of the child’s brain enables education i.e., the necessary experience for maturation of well-adaptive constructs of internal representations, such as mature well-developed optimal DMS (or ego if you will). Now imagine the enormous potential of correcting mal-educated non-adaptive internal-configurations if the patient’s brain can be ‘‘pulled-back’’ in time, and induction of plasticity can ‘‘bring’’ the brain back in time to have the capability of the child’s brain. Think of a plasticity-induced time-window for correction and what a powerful tool can that become. It is important to remember that if a powerful medicationinduced plasticity-window can be achieved our experiencedependent interventions (i.e., the various types of psychotherapies, from dynamic, to cognitive and supportive) must become more organized and better directed to targets specifically identified (diagnosed) in the mal-developed DMN and its SWN internal configurations. The first step would be to recognize that all psychotherapies are aspects or versions of EDP-therapy, in fact switching from terminology which is not-brain-related to that which is related to the brain, then changing the title of ‘‘Psychotherapy’’ to EDP-therapy is advantageous and neuroscientifically more informative. Two modes are available to try and classify the various types of psychotherapy under the framework of EDP-therapy. One directed to targeting a specific result, i.e., one of improving brain organization, and the other based upon the psychotherapy technique (supportive, cognitive, or dynamic insight-oriented). Here targeting improved brain organization is chosen, but as typically turns out, there is substantial correlation between techniques and therapeutic targets. Targets for improved brain organization can roughly be divided into two; first a general developmental target to globally advance, mature and optimize the internal representations; second, specific function-related targeted interventions directed to improve specific distorted maladaptive representations which are critically involved in limited areas of function and perception. These circumscribed targets can generally be defined as ‘‘sensitivity’’ of personality to specific situations or occurrences. These two orientations also have different levels. The superficial level involves straight-forward consciousness (global brain organizations, see Bernard Baars above) requires psychotherapy intervention along the lines of cognitive behavioral therapy, and similar techniques including interventions that are related to psychodrama
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and art therapy. At this level targeting more circumscribed targets such as desensitization techniques in phobias, are appropriate. The more complicated level involves internal representations structurally incorporated in the brain connectivity configurations are unconscious because they do not always participate in global organizations (see above). At this level insight oriented psychodynamic techniques are effective. These are typically relevant to circumscribed issues of self-esteem, and sensitivities to criticism (narcissistic personality disorders). General global maturating therapy for undeveloped internal representations and DMNs can entail the general mother–child transference model and the psychological ‘‘re-growing’’ dynamics for developing a more mature personality. It is evident, from the above description, that the different psychotherapies developed over the years, are not to be abandoned, but rather re-conceptualized as EDP-therapies. They can now become developed toward diagnosable disturbances within the maps of internal configurations and different pathologies of DMN organizations. Furthermore they need to be coupled with medication-induced plasticity time-windows that enable powerful corrective-changes of brain organization.
Verification of plasticity inducing corrective therapies for personality disorders, There is an increasing body of evidence pointing to a relationship between personality and brain markers. Wei et al. [16] studied associations between personality dimensions of extraversion and neuroticism and the local synchronization of spontaneous blood oxygen level-dependent activity assessed by regional homogeneity approach. Their results revealed the significant negative correlation between neuroticism and regional homogeneity in the left middle frontal gyrus, providing evidence for the left frontal activation involved in pleasant emotion. Regional homogeneity was correlated negatively with extraversion in the medial prefrontal cortex, an important portion of the default mode network, thus further indicating the relationship between DMN and personality. In addition, regional homogeneity in the insula, cerebellum and cingulate gyrus was correlated positively with extraversion, suggesting the associations between individual difference in extraversion and specific brain regions involved in affective processing. These findings shed light on the important relationship between the synchronization of spontaneous fluctuations and personality dimensions of extraversion and neuroticism, which provide further evidence for the neural underpinning of individual difference in personality traits. A quantitative meta-analysis that included 87 studies, representing 1433 participants, was conducted by Qin and Northoff [13] to discuss the relationship between the self and resting state activity, as reflected by the default-mode network. Results suggest that our sense of self may result from a specific kind of interaction between resting state activity and stimulus-induced activity, i.e., rest-stimulus interaction, within the midline brain regions. Volkow et al. [15] uncovered an association between positive emotionality and baseline metabolism in regions from the DMN, which suggests that positive emotionality may relate to global cortical processes that are active during resting conditions. Several functional neuroimaging studies have reported regionally abnormal activation of the frontal cortex in individuals with borderline personality disorder. Wolf et al. [17] found within a network comprising cortical midline regions (‘‘default mode network’’), patients with borderline personality disorder showed an increase in functional connectivity in the left frontopolar cortex and the left insula, whereas decreased connectivity was found in the left cuneus. Within a network comprising predominantly right lateral prefrontal and bilateral parietal regions, patients with
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borderline personality disorder showed decreased connectivity of the left inferior parietal lobule and the right middle temporal cortex compared with healthy controls. They found correlations between functional connectivity of the frontopolar cortex and measures of impulsivity as well as between connectivity of the insula/cuneus and dissociation tension. Their data suggest that abnormal functional connectivity of temporally coherent restingstate networks may underlie certain symptom clusters in patients with borderline personality disorders. These studies propose the initial possible methodologies that will one day offer a good assessment of the default mode network alterations in personality disordered patients. These same methods will help reveal psychotherapy-related plasticity changes. The field of investigating alterations in brain activity due to psychotherapy is still to be developed however there are initial attempts at this type of investigation for example Berkovich-Ohana et al. [2] show that the DMN can be studied non-invasively by EEG. DMN deactivation was identified during the transition from resting state to a time production task, as lower gamma (25–45 Hz) power over frontal and midline regions. They show that mindfulness meditation practitioners exhibited a trait lower frontal gamma activity, related to narrative self-reference and DMN activity; this is interpreted as mindfulness meditation induces neuroplasticity practice in self-referential from the early stages. If mindfulness meditation can be described as similar in some aspects to insight-inducing psychotherapy as a way to study brain correlates of psychotherapy is possible.
Conflict of interest statement None declared.
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