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Unraveling action selection and inhibitory control mechanisms in a striatal microcircuit model
18
IOP 2016
480 Sampling of time intervals in rhythmic sound sequences: a Beta version Sundeep Teki University of Oxford, Oxford, United Kingdom Natural sounds like speech and music show rich temporal structure, with rapid variations in the timing of constituent sounds. The ability to precisely encode the timing of events is fundamental for sensory processing and behavior. Recent functional imaging work has demonstrated a key role for the striato-thalamo-cortical circuits in the processing of time in regular sound sequences (Teki et al., 2011). At the neurophysiological level, electrophysiological recordings in human participants with electroencephalography (Iversen et al., 2009) and magnetoencephalography (Fujioka et al., 2012) highlight the crucial role of beta oscillations (15-30Hz). Specifically, the strength of beat related induced beta power in sensorimotor cortex decreased (beta suppression) after the beat and then increased preceding the next beat (beta rebound) in the sequence. However, the beta suppression effect is observed regardless of the temporal regularity of the sequence but the beta rebound peak occurs before the next sound only in regular sequences (Fujioka et al., 2012). Complementary neurophysiological recordings in subcortical motor areas like the putamen from awake behaving macaques tapping in synchrony to a metronome also suggest the importance of beta oscillations in internally guided rhythmic behavior (Bartolo and Merchant, 2015). Thus, motor regions of the brain may entrain. At the sensory level, delta oscillations (1-3Hz) have been shown to entrain to the rhythmic sensory input resulting in increased response gain that represent a mechanism for attentional selection in time (Schroeder and Lakatos, 2009), a hypothesis that is consistent with the dynamic attending theory (Jones, 1976). More recently, hierarchical cross-frequency coupling between delta phase and beta power has been shown to represent a putative mechanism for sampling sensory information in time (Arnal et al., 2015), consistent with generative models of predictive coding (Bastos et al., 2012). I will present an updated synthesis of the current state of the literature that although disparate, suggests a consistent picture about the involvement of sensorimotor circuits via oscillatory mechanisms for sampling time intervals in rhythmic sound sequences (Teki, 2014).
doi:10.1016/j.ijpsycho.2016.07.060
475 Unraveling action selection and inhibitory control mechanisms in a striatal microcircuit model Salva Ardida, Jason Sherfeya, Michelle M. McCarthya, Joachim Hassa,b, Nancy Kopella a Department of Mathematics & Statistics, Boston University, Boston, United States b Department of Theoretical Neuroscience, Bernstein Center for Computational Neuroscience, Central Institute of Mental Health, Heidelberg University, Mannheim, Germany Flexible goal-directed behavior builds upon the foundations of context-dependent routing and inhibitory control of dominant, non-relevant sensory-motor responses. Using a computational
framework, we focused on the dynamics supporting these primary cognitive functions, and outline here three novel predictions: (i) Temporal coordination between prefrontal cortex (PFC) and striatum gives rise to a tunable selection of either the direct (GO) or the indirect (NO-GO) pathway of the basal ganglia. Yet, multiple GO ensembles compete to trigger alternative actions in rule-based decision making. In such scenario, rule-selective PFC ensembles show enhanced high beta coherence compared to other ensembles. According to our model, (ii) rule-based increase in presynaptic synchrony guarantees a preferential entrainment of the proper GO ensemble. However, such a bias in PFC is unnoticeable when a subordinate rule is in play. Instead, an alpha rhythm in the dominant-selective PFC ensemble emerges beforehand, once the subordinate rule is cued. This alpha oscillation in PFC is maintained until the stimulus is on and a decision needs to be made. Our model predicts that (iii) the alpha rhythm triggers local GABAergic short-term depression in associated striatal neurons, which interferes with local resonances, hence opening a window of opportunity for acting on non-dominant information. doi:10.1016/j.ijpsycho.2016.07.061
477 Working memory beta-band networks: Neuroplasticity in the congenitally blind Johanna M. Rimmelea,b, Helene Gudi-Mindermannc, Guido Noltea, Brigitte Röderc, Andreas K. Engela a University Medical Center Hamburg-Eppendorf, Department of Neurophysiology and Pathophysiology, Hamburg, Germany b Max Planck Institute for Empirical Aesthetics, Department of Neuroscience, Frankfurt am Main, Germany c University of Hamburg, Biological Psychology and Neuropsychology, Hamburg, Germany Crossmodal reorganization in congenitally blind individuals, such as activation of the visual cortex during non-visual tasks, has been related to compensation for the lack of the visual sense. We used a different working memory training approach to test whether depending on the task, ventral or dorsal parts of visual cortex are integrated into working memory networks in congenitally blind individuals. We expected the activation of visual cortex in new tasks to be associated with changes in large-scale connectivity to the involved working memory networks. Magnetoencephalographic data were recorded during a 2-back task with voices and with tactile motion stimuli prior to and following a working memory training (with voices or tactile stimuli) or a training-control condition. In the auditory 2-back task, working memory training with voices strengthened beta-band (17.5-22.5 Hz) connectivity (imaginary coherency) in the blind but theta-band (2.5-5 Hz) connectivity in the sighted. Crucially, in the blind connectivity increased between areas of the ventral visual stream (occipito-temporal brain areas, particularly the right fusiform face area) and brain areas involved in auditory working memory (inferior frontal, superior temporal, insular cortex). In the tactile 2-back task, working memory training with tactile stimuli strengthened beta-band connectivity in the blind between occipital and frontal brain areas. Our findings demonstrate that large-scale interactions are a key mechanism of functional specific reorganization following congenital blindness. doi:10.1016/j.ijpsycho.2016.07.062
IOP 2016
480 Sampling of time intervals in rhythmic sound sequences: a Beta version Sundeep Teki University of Oxford, Oxford, United Kingdom Natural sounds like speech and music show rich temporal structure, with rapid variations in the timing of constituent sounds. The ability to precisely encode the timing of events is fundamental for sensory processing and behavior. Recent functional imaging work has demonstrated a key role for the striato-thalamo-cortical circuits in the processing of time in regular sound sequences (Teki et al., 2011). At the neurophysiological level, electrophysiological recordings in human participants with electroencephalography (Iversen et al., 2009) and magnetoencephalography (Fujioka et al., 2012) highlight the crucial role of beta oscillations (15-30Hz). Specifically, the strength of beat related induced beta power in sensorimotor cortex decreased (beta suppression) after the beat and then increased preceding the next beat (beta rebound) in the sequence. However, the beta suppression effect is observed regardless of the temporal regularity of the sequence but the beta rebound peak occurs before the next sound only in regular sequences (Fujioka et al., 2012). Complementary neurophysiological recordings in subcortical motor areas like the putamen from awake behaving macaques tapping in synchrony to a metronome also suggest the importance of beta oscillations in internally guided rhythmic behavior (Bartolo and Merchant, 2015). Thus, motor regions of the brain may entrain. At the sensory level, delta oscillations (1-3Hz) have been shown to entrain to the rhythmic sensory input resulting in increased response gain that represent a mechanism for attentional selection in time (Schroeder and Lakatos, 2009), a hypothesis that is consistent with the dynamic attending theory (Jones, 1976). More recently, hierarchical cross-frequency coupling between delta phase and beta power has been shown to represent a putative mechanism for sampling sensory information in time (Arnal et al., 2015), consistent with generative models of predictive coding (Bastos et al., 2012). I will present an updated synthesis of the current state of the literature that although disparate, suggests a consistent picture about the involvement of sensorimotor circuits via oscillatory mechanisms for sampling time intervals in rhythmic sound sequences (Teki, 2014).
doi:10.1016/j.ijpsycho.2016.07.060
475 Unraveling action selection and inhibitory control mechanisms in a striatal microcircuit model Salva Ardida, Jason Sherfeya, Michelle M. McCarthya, Joachim Hassa,b, Nancy Kopella a Department of Mathematics & Statistics, Boston University, Boston, United States b Department of Theoretical Neuroscience, Bernstein Center for Computational Neuroscience, Central Institute of Mental Health, Heidelberg University, Mannheim, Germany Flexible goal-directed behavior builds upon the foundations of context-dependent routing and inhibitory control of dominant, non-relevant sensory-motor responses. Using a computational
framework, we focused on the dynamics supporting these primary cognitive functions, and outline here three novel predictions: (i) Temporal coordination between prefrontal cortex (PFC) and striatum gives rise to a tunable selection of either the direct (GO) or the indirect (NO-GO) pathway of the basal ganglia. Yet, multiple GO ensembles compete to trigger alternative actions in rule-based decision making. In such scenario, rule-selective PFC ensembles show enhanced high beta coherence compared to other ensembles. According to our model, (ii) rule-based increase in presynaptic synchrony guarantees a preferential entrainment of the proper GO ensemble. However, such a bias in PFC is unnoticeable when a subordinate rule is in play. Instead, an alpha rhythm in the dominant-selective PFC ensemble emerges beforehand, once the subordinate rule is cued. This alpha oscillation in PFC is maintained until the stimulus is on and a decision needs to be made. Our model predicts that (iii) the alpha rhythm triggers local GABAergic short-term depression in associated striatal neurons, which interferes with local resonances, hence opening a window of opportunity for acting on non-dominant information. doi:10.1016/j.ijpsycho.2016.07.061
477 Working memory beta-band networks: Neuroplasticity in the congenitally blind Johanna M. Rimmelea,b, Helene Gudi-Mindermannc, Guido Noltea, Brigitte Röderc, Andreas K. Engela a University Medical Center Hamburg-Eppendorf, Department of Neurophysiology and Pathophysiology, Hamburg, Germany b Max Planck Institute for Empirical Aesthetics, Department of Neuroscience, Frankfurt am Main, Germany c University of Hamburg, Biological Psychology and Neuropsychology, Hamburg, Germany Crossmodal reorganization in congenitally blind individuals, such as activation of the visual cortex during non-visual tasks, has been related to compensation for the lack of the visual sense. We used a different working memory training approach to test whether depending on the task, ventral or dorsal parts of visual cortex are integrated into working memory networks in congenitally blind individuals. We expected the activation of visual cortex in new tasks to be associated with changes in large-scale connectivity to the involved working memory networks. Magnetoencephalographic data were recorded during a 2-back task with voices and with tactile motion stimuli prior to and following a working memory training (with voices or tactile stimuli) or a training-control condition. In the auditory 2-back task, working memory training with voices strengthened beta-band (17.5-22.5 Hz) connectivity (imaginary coherency) in the blind but theta-band (2.5-5 Hz) connectivity in the sighted. Crucially, in the blind connectivity increased between areas of the ventral visual stream (occipito-temporal brain areas, particularly the right fusiform face area) and brain areas involved in auditory working memory (inferior frontal, superior temporal, insular cortex). In the tactile 2-back task, working memory training with tactile stimuli strengthened beta-band connectivity in the blind between occipital and frontal brain areas. Our findings demonstrate that large-scale interactions are a key mechanism of functional specific reorganization following congenital blindness. doi:10.1016/j.ijpsycho.2016.07.062