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Social and Behavioral Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Western University

2014

Prefrontal Cortex

Articles 1 - 4 of 4

Full-Text Articles in Social and Behavioral Sciences

Transcranial Magnetic Stimulation Of The Prefrontal Cortex In Awake Nonhuman Primates Evokes A Polysynaptic Neck Muscle Response That Reflects Oculomotor Activity At The Time Of Stimulation., Chao Gu, Brian D Corneil Oct 2014

Transcranial Magnetic Stimulation Of The Prefrontal Cortex In Awake Nonhuman Primates Evokes A Polysynaptic Neck Muscle Response That Reflects Oculomotor Activity At The Time Of Stimulation., Chao Gu, Brian D Corneil

Brain and Mind Institute Researchers' Publications

Transcranial magnetic stimulation (TMS) has emerged as an important technique in cognitive neuroscience, permitting causal inferences about the contribution of a given brain area to behavior. Despite widespread use, exactly how TMS influences neural activity throughout an interconnected network, and how such influences ultimately change behavior, remain unclear. The oculomotor system of nonhuman primates (NHPs) offers a potential animal model to bridge this gap. Here, based on results suggesting that neck muscle activity provides a sensitive indicator of oculomotor activation, we show that single pulses of TMS over the frontal eye fields (FEFs) in awake NHPs evoked rapid (within ∼25 …


Sharp Emergence Of Feature-Selective Sustained Activity Along The Dorsal Visual Pathway., Diego Mendoza-Halliday, Santiago Torres, Julio C Martinez-Trujillo Sep 2014

Sharp Emergence Of Feature-Selective Sustained Activity Along The Dorsal Visual Pathway., Diego Mendoza-Halliday, Santiago Torres, Julio C Martinez-Trujillo

Brain and Mind Institute Researchers' Publications

Sustained activity encoding visual working memory representations has been observed in several cortical areas of primates. Where along the visual pathways this activity emerges remains unknown. Here we show in macaques that sustained spiking activity encoding memorized visual motion directions is absent in direction-selective neurons in early visual area middle temporal (MT). However, it is robustly present immediately downstream, in multimodal association area medial superior temporal (MST), as well as and in the lateral prefrontal cortex (LPFC). This sharp emergence of sustained activity along the dorsal visual pathway suggests a functional boundary between early visual areas, which encode sensory inputs, …


Human Premotor Areas Parse Sequences Into Their Spatial And Temporal Features., Katja Kornysheva, Jörn Diedrichsen Aug 2014

Human Premotor Areas Parse Sequences Into Their Spatial And Temporal Features., Katja Kornysheva, Jörn Diedrichsen

Brain and Mind Institute Researchers' Publications

Skilled performance is characterized by precise and flexible control of movement sequences in space and time. Recent theories suggest that integrated spatio-temporal trajectories are generated by intrinsic dynamics of motor and premotor networks. This contrasts with behavioural advantages that emerge when a trained spatial or temporal feature of sequences is transferred to a new spatio-temporal combination arguing for independent neural representations of these sequence features. We used a new fMRI pattern classification approach to identify brain regions with independent vs integrated representations. A distinct regional dissociation within motor areas was revealed: whereas only the contralateral primary motor cortex exhibited unique …


Activation Of Mglur2/3 Receptors In The Ventro-Rostral Prefrontal Cortex Reverses Sensorimotor Gating Deficits Induced By Systemic Nmda Receptor Antagonists., Bridget Valsamis, Michael Chang, Marei Typlt, Susanne Schmid Feb 2014

Activation Of Mglur2/3 Receptors In The Ventro-Rostral Prefrontal Cortex Reverses Sensorimotor Gating Deficits Induced By Systemic Nmda Receptor Antagonists., Bridget Valsamis, Michael Chang, Marei Typlt, Susanne Schmid

Brain and Mind Institute Researchers' Publications

Prepulse inhibition (PPI) of acoustic startle is an operational measure of sensorimotor gating, which is disrupted in schizophrenia. NMDA receptor (NMDAR) antagonist induced PPI disruption has become an important pharmacological model for schizophrenia; however, knowledge of the underlying mechanism remains incomplete. This study examines the role of NMDAR in the caudal pontine reticular nucleus (PnC) and the medial prefrontal cortex (mPFC) in NMDARs antagonist induced PPI deficits, as well as the NMDA receptor subtypes involved. We administered the NMDA antagonist MK-801 locally into the caudal pontine reticular formation (PnC), where the PPI mediating pathway converges with the primary startle pathway, …