Emotional coding and reactivity in Multiple Sclerosis

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IOP 2016

historical context, the clinical definition and the semiology of the Tourette syndrome. The second part will introduce our research program, as well as a methodology for the integration of electrophysiological methods in the treatment and evaluation of symptoms related to chronic tics. Methods: The event-related potentials (ERP) and lateralized readiness potentials (LRP) were recorded before and after treatment, with 20 tic disorders patients and 20 healthy control participants, matched on age, sex and intelligence, during a stimulus-response compatibility inhibition task. The cognitive-behavioural therapy included informational, awareness training, relaxation, muscle discrimination, cognitive restructuration and relapse prevention strategies. Results: Our results revealed that prior to treatment; tic patients had delayed stimulus-locked LRP onset latency, larger response-locked LRP peak amplitude, and a frontal overactivation during stimulus inhibition processing. Both stimulus-locked LRP onset latency and responselocked LRP peak amplitude normalized after the cognitive behavioural therapy completion. However, the frontal overactivation related to inhibition remained unchanged following therapy. Discussion: The overactivity of the frontal component and the impulsivity in observed in patients were not affected by treatment. However, CBT had normalizing effects on the activation of the LRP that reflects pre-motor and motor cortex activation. These results imply specific modifications of motor processes following therapy, while inhibition processes remained unchanged. Given that LRPs are partially generated within the sensorimotor and supplementary motor area, the reported reduction in tic frequency and improvements of LRPs components suggest that CBT induced a physiological change in patients’ motor area. The originality of our results support, singularly, the presence of a measurable electrocortical change following these cognitive and behavioral modification.

doi:10.1016/j.ijpsycho.2016.07.197

468 Investigation of the neural correlates of working memory functioning in schizophrenia: evidence for a selective deficit of intentional binding David Luck Université de Montréal, Montréal, Canada Source memory deficits have been widely reported in schizophrenia, and may result from inefficient binding processes in working memory (WM). Thus, we designed an fMRI study aimed at investigating the neural correlates of both incidental and intentional binding in working memory in schizophrenia. Nineteen patients with schizophrenia and 23 matched controls were recruited to perform a working memory binding task, in which they were instructed to memorize three letters and three spatial locations. In the incidental binding condition, letters and spatial locations were directly presented as bound. By contrast, letters and spatial locations were presented as separated in the intentional binding condition, and participants were instructed to voluntary create associations between verbal and spatial information. Patients with exhibited equal performance for incidental binding than controls, but lower performance for intentional binding. FMRI analyses revealed that this deficit for intentional binding was related to aberrant activity in the posterior parietal cortex and in the ventrolateral prefrontal cortex. This study provides evidence of a specific deficit for intentionally bound information in schizophrenia, resulting from dysfunctions in the cerebral networks underlying attention, encoding strategies, and cognitive control. Together, our results suggest that all these

dysfunctions may be targets for neuromodulation interventions known to improve cognitive deficits in schizophrenia. doi:10.1016/j.ijpsycho.2016.07.198

Analytic and Real Time sLORETA QEEG in Recovery of Acute Sport-Related Concussion Harry Kerasidis Calvert Memorial Neuroscience Center Introduction/support: Concussion is a complex pathophysiologic process affecting the brain, induced by biomechanical forces (McCrory et al., 2013). Electroencephalography (EEG) measures differences in neuron-generated electrical potentials, and concussion results in measurable EEG abnormalities (Rapp et al., 2015). Three dimensional current source density analysis utilizing standardized low resolution electromagnetic tomography (sLORETA) integrated with Quantitative EEG (QEEG) normative database techniques allows for high precision localization of cerebral physiology.HYPOTHESIS/JUSTIFICATION. QEEG analysis can be integrated into a comprehensive symptom and cognitive performance based program to further our understanding of the concussion recovery process. We hypothesize that QEEG, particularly sLORETA analysis parallels concussion injury recovery. Methods: The sport arena provides a semi-controlled environment where the effects of brain trauma can be observed, presenting a unique opportunity to study the natural course of concussion injury and recovery in athletes by standard concussion management programs integrated with QEEG. QEEG data is acquired post-concussion and when cognitive measures return-to-baseline. QEEG and sLORETA data at these time points are compared. We examine the relationship between QEEG metrics and neurocognitive measures in the recovery process. Results: Two patterns of QEEG changes emerge in this analysis: (1) regional increase in delta/theta activity, particularly in the frontal and temporal lobes, and (2) regional and often generalized increase in beta/ gamma activity. Resolution of the increased slow wave activity parallels symptom and cognitive performance recovery from concussion injury, while changes in gamma activity are more often persistent after clinical resolution. Conclusion: This study suggests that changes in cerebral electrophysiology persist beyond current standards of determination of clinical recovery. We hypothesize the generalized increase in gamma activity represents cortical-cortical communication in the wake of deafferentation from deeper thalamic and brainstem structures due to axonal injury, while increased slow wave activity depicts regional cortical dysfunction due to direct trauma. Our findings suggest persistent pathophysiologic changes that may play a significant role in clinical return to play decision making and neurotheraputic protocol design. We propose that QEEG analysis should be included in baseline assessments of athletes and other individuals prone to concussion injury so direct within-individual comparisons can be made. Further research is needed to more definitively characterize the relationship between QEEG and recovery from injury. doi:10.1016/j.ijpsycho.2016.07.199

533 Emotional coding and reactivity in Multiple Sclerosis Henrique Sequeira University of Lille, Faculty of Sciences & Faculty of Medicine Neurosciences, Lille, France

IOP 2016

Multiple sclerosis (MS) is characterized by lesions of myelin, which result in a broad range of symptoms including motor, cognitive and psychiatric disorders. More recently, emotional dysfunctions have been reported as clinical signs appearing in early steps of the disease. Considering the adaptive value of emotional coding in social exchanges, several authors tried to better understand the role of emotion in MS behaviors and their potential impact in the well-being of patients. Some studies tried on one hand to disentangle emotional components from cognitive, sensory or motor impairments and on the other hand to identify and to characterize mechanisms subtending emotional reactivity in MS. In this presentation we aimed, firstly to review data from the literature related to the exploration of emotional facets in MS and, secondly, to investigate the ability of patients with Relapsing-Remitting Multiple Sclerosis (RRMS) to recognize emotional facial expressions (EFE). To this end, cognitive, affective and executive functions were assessed in fifteen RRMS patients and in fifteen controls, matched for age, sex, educational level and laterality. Behavioral (emotional categorization, reaction time and emotional intensity evaluation) and brain reactivity (P100 and N170 evoked components) were recorded in both groups during a task testing the recognition of fifteen morphs of emotional (anger, joy; low and high intensities) and neutral facial expressions. Results showed that, compared to controls, RRMS presented a deficit to categorize low intensities of anger expressions. Moreover, patients manifested a significant difficulty to estimate the intensity of anger and joy facial expressions. RRMS patients also showed a significant decrease of the P100 amplitude and an increase of the latency of the N170 to the presentation of EFE. Reported data seem to indicate a difficulty to RRMS patients to discriminate the emotional value of EFE; in addition, the related cerebral coding appears to engage fewer and slowed resources when compared with healthy participants. Thus, obtained data sustain the existence of a difficulty to integrate emotional facial information in RRMS patients. Overall, this study encourages the exploration of such deficit in order to optimize the emotional regulation, a main factor of quality of life in MS patients.

doi:10.1016/j.ijpsycho.2016.07.200

50 Symposium B7 Mobile Phone and Electromagnetic Field Exposure and the Brain: Current Knowledge and Research Gaps Sarah Loughran (Australia) Telecommunications technologies, such as mobile phones, have developed rapidly and their use is now ubiquitous. This widespread and rapid increase in use has led to considerable concern regarding potential impacts that exposure to the radiofrequency electromagnetic fields (RF-EMF) and extremely low frequency magnetic fields (ELF-MF) emitted by these devices may have on human health. Of particular concern is the brain and brain function, as a substantial portion of the EMF is absorbed by the human head during normal use. Although a range of endpoints have been investigated and some reported to be affected by RF-EMF exposure, the vast majority of these have not withstood the test of replication (van Rongen et al., 2009). Conversely, subtle RF-EMF-induced changes to neural function, as measured by the electroencephalograph (EEG), have been reliably demonstrated with effects consistently seen on alpha activity during wake, and alpha and sleep spindle frequencies during sleep (Borbely et al., 1999; Croft et al.,

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2008; Croft et al., 2010; Huber et al., 2003; Loughran et al., 2012; Loughran et al., 2005; Regel et al., 2007; Schmid et al., 2012a; Schmid et al., 2012b). These effects have been replicated in independent laboratories, and have also been shown to be dose-dependent (Regel et al., 2007) and sensitive to individual differences (Loughran et al., 2012). Reacting to this, the World Health Organisation (WHO, 2010) identified as ‘high priority’, research questions that it argued needed to be addressed in order to clarify the relative impact of RF-EMF on human health. Specifically, it called for research to determine the neurobiological mechanisms underlying RF-induced effect on the EEG, to better understand both the mechanisms responsible for this effect as well as the neural processes themselves. This symposium will address the current state of knowledge and research gaps regarding RF-EMF and ELF-MF exposures and four measures of neural function: 1/ Sleep and the sleep EEG; 2/ Resting EEG; 3/ Event-related potentials; and 4/ Acute visual perceptions (magnetophosphenes).

doi:10.1016/j.ijpsycho.2016.07.201

488 Mobile Phone Emissions and the Sleeping Brain Sarah Loughran Australian Centre for Electromagnetic Bioeffects Research, Wollongong, Australia University of Wollongong, Wollongong, Australia The widespread and rapid increase in use of technologies, such as mobile phones, has led to concern regarding possible impacts that exposure to the radiofrequency (RF) electromagnetic fields (EMF) emitted by these devices may have on human health, and there is now evidence that mobile phone-like exposures affect electrical brain activity. Although early reports of such effects were inconsistent and suffering from serious methodological limitations, these have now been replicated repeatedly with strong methodologies, showing an effects of RF EMF exposure on the alpha and spindle frequency ranges during sleep (Huber et al., 2003; Loughran et al., 2005, 2012; Regel et al., 2007; Schmid et al., 2012). These effects have also been shown to be dose-dependent (Regel et al., 2007) as well as sensitive to individual variability (Loughran et al., 2012). Despite this, the underlying neurobiological mechanisms, functional consequences, and potential presence of this effect in children, remains unknown. In response to the concern and uncertainty regarding mobile phones and health, the World Health Organisation has identified studies in children of different ages, as well as studies validating effects on the EEG and identifying mechanisms, as high priority research needs. A series of studies are currently underway to address these issues, determining (1) Whether the EEG effect is consistent with an RF-induced thermal change using both the awake and sleep EEG; (2) The sensitivity of children and adolescents sleep to RF; (3) The influence of gender and circadian cycle on the EEG effect; and (4) The functional consequences of the effect on the EEG. This presentation will review the previous work on RF and sleep, discuss the open questions and how the current research at the Australian Centre for Electromagnetic Bioeffects Research is addressing this, and how previous and future research can be translated and contribute to health policy and RF safety standards.

doi:10.1016/j.ijpsycho.2016.07.202