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Functional Organization Of Frontoparietal Cortex In The Marmoset Investigated With Awake Resting-State Fmri, Yuki Hori, Justine C. Cléry, David J. Schaeffer, Ravi S. Menon, Stefan Everling Sep 2021

Functional Organization Of Frontoparietal Cortex In The Marmoset Investigated With Awake Resting-State Fmri, Yuki Hori, Justine C. Cléry, David J. Schaeffer, Ravi S. Menon, Stefan Everling

Brain and Mind Institute Researchers' Publications

Frontoparietal networks contribute to complex cognitive functions in humans and macaques, such as working memory, attention, task-switching, response suppression, grasping, reaching, and eye movement control. However, there has been no comprehensive examination of the functional organization of frontoparietal networks using functional magnetic resonance imaging in the New World common marmoset monkey (Callithrix jacchus), which is now widely recognized as a powerful nonhuman primate experimental animal. In this study, we employed hierarchical clustering of interareal blood oxygen level-dependent signals to investigate the hypothesis that the organization of the frontoparietal cortex in the marmoset follows the organizational principles of the macaque frontoparietal …


Cortico-Subcortical Functional Connectivity Profiles Of Resting-State Networks In Marmosets And Humans, Yuki Hori, David J. Schaeffer, Atsushi Yoshida, Justine C. Cléry, Lauren K. Hayrynen, Joseph S. Gati, Ravi S. Menon, Stefan Everling Nov 2020

Cortico-Subcortical Functional Connectivity Profiles Of Resting-State Networks In Marmosets And Humans, Yuki Hori, David J. Schaeffer, Atsushi Yoshida, Justine C. Cléry, Lauren K. Hayrynen, Joseph S. Gati, Ravi S. Menon, Stefan Everling

Brain and Mind Institute Researchers' Publications

Copyright © 2020 the authors Understanding the similarity of cortico-subcortical networks topologies between humans and nonhuman primate species is critical to study the origin of network alternations underlying human neurologic and neuropsychiatric diseases. The New World common marmoset (Callithrix jacchus) has become popular as a nonhuman primate model for human brain function. Most marmoset connectomic research, however, has exclusively focused on cortical areas, with connectivity to subcortical networks less extensively explored. Here, we aimed to first isolate patterns of subcortical connectivity with cortical resting-state networks in awake marmosets using resting-state fMRI, then to compare these networks with those in humans …


Functional Localization Of The Frontal Eye Fields In The Common Marmoset Using Microstimulation, Janahan Selvanayagam, Kevin D. Johnston, David J. Schaeffer, Lauren K. Hayrynen, Stefan Everling Nov 2019

Functional Localization Of The Frontal Eye Fields In The Common Marmoset Using Microstimulation, Janahan Selvanayagam, Kevin D. Johnston, David J. Schaeffer, Lauren K. Hayrynen, Stefan Everling

Brain and Mind Institute Researchers' Publications

Copyright © 2019 the authors. The frontal eye field (FEF) is a critical region for the deployment of overt and covert spatial attention. Although investigations in the macaque continue to provide insight into the neural underpinnings of the FEF, due to its location within a sulcus, the macaque FEF is virtually inaccessible to electrophysiological techniques such as high-density and laminar recordings. With a largely lissencephalic cortex, the common marmoset (Callithrix jacchus) is a promising alternative primate model for studying FEF microcircuitry. Putative homologies have been established with the macaque FEF on the basis of cytoarchitecture and connectivity; however, physiological investigation …


Modified Origins Of Cortical Projections To The Superior Colliculus In The Deaf: Dispersion Of Auditory Efferents., Blake E Butler, Julia K Sunstrum, Stephen G Lomber Apr 2018

Modified Origins Of Cortical Projections To The Superior Colliculus In The Deaf: Dispersion Of Auditory Efferents., Blake E Butler, Julia K Sunstrum, Stephen G Lomber

Brain and Mind Institute Researchers' Publications

Following the loss of a sensory modality, such as deafness or blindness, crossmodal plasticity is commonly identified in regions of the cerebrum that normally process the deprived modality. It has been hypothesized that significant changes in the patterns of cortical afferent and efferent projections may underlie these functional crossmodal changes. However, studies of thalamocortical and corticocortical connections have refuted this hypothesis, instead revealing a profound resilience of cortical afferent projections following deafness and blindness. This report is the first study of cortical outputs following sensory deprivation, characterizing cortical projections to the superior colliculus in mature cats (


Quantifying And Comparing The Pattern Of Thalamic And Cortical Projections To The Posterior Auditory Field In Hearing And Deaf Cats., Blake E Butler, Nicole Chabot, Stephen G Lomber Oct 2016

Quantifying And Comparing The Pattern Of Thalamic And Cortical Projections To The Posterior Auditory Field In Hearing And Deaf Cats., Blake E Butler, Nicole Chabot, Stephen G Lomber

Brain and Mind Institute Researchers' Publications

Following sensory loss, compensatory crossmodal reorganization occurs such that the remaining modalities are functionally enhanced. For example, behavioral evidence suggests that peripheral visual localization is better in deaf than in normal hearing animals, and that this enhancement is mediated by recruitment of the posterior auditory field (PAF), an area that is typically involved in localization of sounds in normal hearing animals. To characterize the anatomical changes that underlie this phenomenon, we identified the thalamic and cortical projections to the PAF in hearing cats and those with early- and late-onset deafness. The retrograde tracer biotinylated dextran amine was deposited in the …


A Quantitative Comparison Of The Hemispheric, Areal, And Laminar Origins Of Sensory And Motor Cortical Projections To The Superior Colliculus Of The Cat., Blake E Butler, Nicole Chabot, Stephen G Lomber Sep 2016

A Quantitative Comparison Of The Hemispheric, Areal, And Laminar Origins Of Sensory And Motor Cortical Projections To The Superior Colliculus Of The Cat., Blake E Butler, Nicole Chabot, Stephen G Lomber

Brain and Mind Institute Researchers' Publications

The superior colliculus (SC) is a midbrain structure central to orienting behaviors. The organization of descending projections from sensory cortices to the SC has garnered much attention; however, rarely have projections from multiple modalities been quantified and contrasted, allowing for meaningful conclusions within a single species. Here, we examine corticotectal projections from visual, auditory, somatosensory, motor, and limbic cortices via retrograde pathway tracers injected throughout the superficial and deep layers of the cat SC. As anticipated, the majority of cortical inputs to the SC originate in the visual cortex. In fact, each field implicated in visual orienting behavior makes a …


Functional Differences Between Statistical Learning With And Without Explicit Training., Laura J Batterink, Paul J Reber, Ken A Paller Nov 2015

Functional Differences Between Statistical Learning With And Without Explicit Training., Laura J Batterink, Paul J Reber, Ken A Paller

Brain and Mind Institute Researchers' Publications

Humans are capable of rapidly extracting regularities from environmental input, a process known as statistical learning. This type of learning typically occurs automatically, through passive exposure to environmental input. The presumed function of statistical learning is to optimize processing, allowing the brain to more accurately predict and prepare for incoming input. In this study, we ask whether the function of statistical learning may be enhanced through supplementary explicit training, in which underlying regularities are explicitly taught rather than simply abstracted through exposure. Learners were randomly assigned either to an explicit group or an implicit group. All learners were exposed to …


Differential Modification Of Cortical And Thalamic Projections To Cat Primary Auditory Cortex Following Early- And Late-Onset Deafness., Nicole Chabot, Blake E Butler, Stephen G Lomber Oct 2015

Differential Modification Of Cortical And Thalamic Projections To Cat Primary Auditory Cortex Following Early- And Late-Onset Deafness., Nicole Chabot, Blake E Butler, Stephen G Lomber

Brain and Mind Institute Researchers' Publications

Following sensory deprivation, primary somatosensory and visual cortices undergo crossmodal plasticity, which subserves the remaining modalities. However, controversy remains regarding the neuroplastic potential of primary auditory cortex (A1). To examine this, we identified cortical and thalamic projections to A1 in hearing cats and those with early- and late-onset deafness. Following early deafness, inputs from second auditory cortex (A2) are amplified, whereas the number originating in the dorsal zone (DZ) decreases. In addition, inputs from the dorsal medial geniculate nucleus (dMGN) increase, whereas those from the ventral division (vMGN) are reduced. In late-deaf cats, projections from the anterior auditory field (AAF) …


Nicotine Receptors Mediating Sensorimotor Gating And Its Enhancement By Systemic Nicotine., Farena Pinnock, Daniel Bosch, Tyler Brown, Nadine Simons, John R Yeomans, Cleusa Deoliveira, Susanne Schmid Jan 2015

Nicotine Receptors Mediating Sensorimotor Gating And Its Enhancement By Systemic Nicotine., Farena Pinnock, Daniel Bosch, Tyler Brown, Nadine Simons, John R Yeomans, Cleusa Deoliveira, Susanne Schmid

Brain and Mind Institute Researchers' Publications

Prepulse inhibition (PPI) of startle occurs when intensity stimuli precede stronger startle-inducing stimuli by 10-1000 ms. PPI deficits are found in individuals with schizophrenia and other psychiatric disorders, and they correlate with other cognitive impairments. Animal research and clinical studies have demonstrated that both PPI and cognitive function can be enhanced by nicotine. PPI has been shown to be mediated, at least in part, by mesopontine cholinergic neurons that project to pontine startle neurons and activate muscarinic and potentially nicotine receptors (nAChRs). The subtypes and anatomical location of nAChRs involved in mediating and modulating PPI remain unresolved. We tested the …


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 …


Self-Injurious Behaviours Are Associated With Alterations In The Somatosensory System In Children With Autism Spectrum Disorder., Emma G Duerden, Dallas Card, S Wendy Roberts, Kathleen M Mak-Fan, M Mallar Chakravarty, Jason P Lerch, Margot J Taylor Jul 2014

Self-Injurious Behaviours Are Associated With Alterations In The Somatosensory System In Children With Autism Spectrum Disorder., Emma G Duerden, Dallas Card, S Wendy Roberts, Kathleen M Mak-Fan, M Mallar Chakravarty, Jason P Lerch, Margot J Taylor

Brain and Mind Institute Researchers' Publications

Children with autism spectrum disorder (ASD) frequently engage in self-injurious behaviours, often in the absence of reporting pain. Previous research suggests that altered pain sensitivity and repeated exposure to noxious stimuli are associated with morphological changes in somatosensory and limbic cortices. Further evidence from postmortem studies with self-injurious adults has indicated alterations in the structure and organization of the temporal lobes; however, the effect of self-injurious behaviour on cortical development in children with ASD has not yet been determined. Thirty children and adolescents (mean age = 10.6 ± 2.5 years; range 7-15 years; 29 males) with a clinical diagnosis of …


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, …


Links Between White Matter Microstructure And Cortisol Reactivity To Stress In Early Childhood: Evidence For Moderation By Parenting., Haroon I Sheikh, Marc F Joanisse, Sarah M Mackrell, Katie R Kryski, Heather J Smith, Shiva M Singh, Elizabeth P Hayden Jan 2014

Links Between White Matter Microstructure And Cortisol Reactivity To Stress In Early Childhood: Evidence For Moderation By Parenting., Haroon I Sheikh, Marc F Joanisse, Sarah M Mackrell, Katie R Kryski, Heather J Smith, Shiva M Singh, Elizabeth P Hayden

Brain and Mind Institute Researchers' Publications

Activity of the hypothalamic-pituitary-adrenal axis (measured via cortisol reactivity) may be a biological marker of risk for depression and anxiety, possibly even early in development. However, the structural neural correlates of early cortisol reactivity are not well known, although these would potentially inform broader models of mechanisms of risk, especially if the early environment further shapes these relationships. Therefore, we examined links between white matter architecture and young girls' cortisol reactivity and whether early caregiving moderated these links. We recruited 45 6-year-old girls based on whether they had previously shown high or low cortisol reactivity to a stress task at …


Resting-State Connectivity Identifies Distinct Functional Networks In Macaque Cingulate Cortex., R Matthew Hutchison, Thilo Womelsdorf, Joseph S Gati, L Stan Leung, Ravi S Menon, Stefan Everling Jun 2012

Resting-State Connectivity Identifies Distinct Functional Networks In Macaque Cingulate Cortex., R Matthew Hutchison, Thilo Womelsdorf, Joseph S Gati, L Stan Leung, Ravi S Menon, Stefan Everling

Brain and Mind Institute Researchers' Publications

Subregions of the cingulate cortex represent prominent intersections in the structural networks of the primate brain. The relevance of the cingulate to the structure and dynamics of large-scale networks ultimately requires a link to functional connectivity. Here, we map fine-grained functional connectivity across the complete extent of the macaque (Macaca fascicularis) cingulate cortex and delineate subdivisions pertaining to distinct identifiable networks. In particular, we identified 4 primary networks representing the functional spectrum of the cingulate: somatomotor, attention-orienting, executive, and limbic. The cingulate nodes of these networks originated from separable subfields along the rostral-to-caudal axis and were characterized by positive and …


Encoding Of Sensory Prediction Errors In The Human Cerebellum., John Schlerf, Richard B Ivry, Jörn Diedrichsen Apr 2012

Encoding Of Sensory Prediction Errors In The Human Cerebellum., John Schlerf, Richard B Ivry, Jörn Diedrichsen

Brain and Mind Institute Researchers' Publications

A central tenet of motor neuroscience is that the cerebellum learns from sensory prediction errors. Surprisingly, neuroimaging studies have not revealed definitive signatures of error processing in the cerebellum. Furthermore, neurophysiologic studies suggest an asymmetry, such that the cerebellum may encode errors arising from unexpected sensory events, but not errors reflecting the omission of expected stimuli. We conducted an imaging study to compare the cerebellar response to these two types of errors. Participants made fast out-and-back reaching movements, aiming either for an object that delivered a force pulse if intersected or for a gap between two objects, either of which …


Paradoxical Facilitation Of Object Recognition Memory After Infusion Of Scopolamine Into Perirhinal Cortex: Implications For Cholinergic System Function., Boyer D Winters, Lisa M Saksida, Timothy J Bussey Sep 2006

Paradoxical Facilitation Of Object Recognition Memory After Infusion Of Scopolamine Into Perirhinal Cortex: Implications For Cholinergic System Function., Boyer D Winters, Lisa M Saksida, Timothy J Bussey

Brain and Mind Institute Researchers' Publications

The cholinergic system has long been implicated in learning and memory, yet its specific function remains unclear. In the present study, we investigated the role of cortical acetylcholine in a rodent model of declarative memory by infusing the cholinergic muscarinic receptor antagonist scopolamine into the rat perirhinal cortex during different stages (encoding, storage/consolidation, and retrieval) of the spontaneous object recognition task. Presample infusions of scopolamine significantly impaired object recognition compared with performance of the same group of rats on saline trials; this result is consistent with previous reports supporting a role for perirhinal acetylcholine in object information acquisition. Scopolamine infusions …


Glutamate Receptors In Perirhinal Cortex Mediate Encoding, Retrieval, And Consolidation Of Object Recognition Memory., Boyer D Winters, Timothy J Bussey Apr 2005

Glutamate Receptors In Perirhinal Cortex Mediate Encoding, Retrieval, And Consolidation Of Object Recognition Memory., Boyer D Winters, Timothy J Bussey

Brain and Mind Institute Researchers' Publications

Object recognition is consistently impaired in human amnesia and animal models thereof. Results from subjects with permanent brain damage have revealed the importance of the perirhinal cortex to object recognition memory. Here, we report evidence from rats for interdependent but distinct stages in object recognition memory (encoding, retrieval, and consolidation), which require glutamate receptor activity within perirhinal cortex. Transient blockade of AMPA receptor-mediated synaptic transmission within perirhinal cortex disrupted encoding for short- and long-term memory as well as retrieval and consolidation. In contrast, transient NMDA receptor blockade during encoding affected only long-term object recognition memory; NMDA receptor activity was also …


Transient Inactivation Of Perirhinal Cortex Disrupts Encoding, Retrieval, And Consolidation Of Object Recognition Memory., Boyer D Winters, Timothy J Bussey Jan 2005

Transient Inactivation Of Perirhinal Cortex Disrupts Encoding, Retrieval, And Consolidation Of Object Recognition Memory., Boyer D Winters, Timothy J Bussey

Brain and Mind Institute Researchers' Publications

Damage to perirhinal cortex (PRh) impairs object recognition memory in humans, monkeys, and rats when tested in tasks such as delayed nonmatching to sample, visual paired comparison, and its rodent analog, the spontaneous object recognition task. In the present study, we have capitalized on the discrete one-trial nature of the spontaneous object recognition task to investigate the role of PRh in several distinct stages of object recognition memory. In a series of experiments, transient inactivation of PRh was accomplished with bilateral infusions of lidocaine directly into PRh immediately before the sample phase (encoding), immediately before the choice phase (retrieval), or …


Eye Position Signal Modulates A Human Parietal Pointing Region During Memory-Guided Movements., J F Desouza, S P Dukelow, J S Gati, R S Menon, R A Andersen, T Vilis Aug 2000

Eye Position Signal Modulates A Human Parietal Pointing Region During Memory-Guided Movements., J F Desouza, S P Dukelow, J S Gati, R S Menon, R A Andersen, T Vilis

Brain and Mind Institute Researchers' Publications

Using functional magnetic resonance imaging, we examined the signal in parietal regions that were selectively activated during delayed pointing to flashed visual targets and determined whether this signal was dependent on the fixation position of the eyes. Delayed pointing activated a bilateral parietal area in the intraparietal sulcus (rIPS), rostral/anterior to areas activated by saccades. During right-hand pointing to centrally located targets, the left rIPS region showed a significant increase in activation when the eye position was rightward compared with leftward. As expected, activation in motor cortex showed no modulation when only eye position changed. During pointing to retinotopically identical …