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Dopaminergic Modulation Of Medial Prefrontal Cortex Deactivation In Parkinson Depression, Anders H. Andersen, Charles D. Smith, John T. Slevin, Richard J. Kryscio, Catherine A. Martin, Frederick A. Schmitt, Lee X. Blonder Nov 2015

Dopaminergic Modulation Of Medial Prefrontal Cortex Deactivation In Parkinson Depression, Anders H. Andersen, Charles D. Smith, John T. Slevin, Richard J. Kryscio, Catherine A. Martin, Frederick A. Schmitt, Lee X. Blonder

Neuroscience Faculty Publications

Parkinson's disease (PD) is associated with emotional abnormalities. Dopaminergic medications ameliorate Parkinsonian motor symptoms, but less is known regarding the impact of dopaminergic agents on affective processing, particularly in depressed PD (dPD) patients. The aim of this study was to examine the effects of dopaminergic pharmacotherapy on brain activation to emotional stimuli in depressed versus nondepressed Parkinson disease (ndPD) patients. Participants included 18 ndPD patients (11 men, 7 women) and 10 dPD patients (7 men, 3 women). Patients viewed photographs of emotional faces during functional MRI. Scans were performed while the patient was taking anti-Parkinson medication and the day after …


White Matter Microstructure Contributes To Age-Related Declines In Task-Induced Deactivation Of The Default Mode Network, Christopher A. Brown, Jonathan G. Hakun, Zude Zhu, Nathan F. Johnson, Brian T. Gold Oct 2015

White Matter Microstructure Contributes To Age-Related Declines In Task-Induced Deactivation Of The Default Mode Network, Christopher A. Brown, Jonathan G. Hakun, Zude Zhu, Nathan F. Johnson, Brian T. Gold

Neuroscience Faculty Publications

Task-induced deactivations within the brain’s default mode network (DMN) are thought to reflect suppression of endogenous thought processes to support exogenous goal-directed task processes. Older adults are known to show reductions in deactivation of the DMN compared to younger adults. However, little is understood about the mechanisms contributing to functional dysregulation of the DMN in aging. Here, we explored the relationships between functional modulation of the DMN and age, task performance and white matter (WM) microstructure. Participants were 117 adults ranging from 25 to 83 years old who completed an fMRI task switching paradigm, including easy (single) and difficult (mixed) …


The Foot Of Homo Naledi, W. E. H. Harcourt-Smith, Z. Throckmorton, K. A. Congdon, B. Zipfel, Andrew S. Deane, M. S. M. Drapeau, S. E. Churchill, L. R. Berger, J. M. Desilva Oct 2015

The Foot Of Homo Naledi, W. E. H. Harcourt-Smith, Z. Throckmorton, K. A. Congdon, B. Zipfel, Andrew S. Deane, M. S. M. Drapeau, S. E. Churchill, L. R. Berger, J. M. Desilva

Neuroscience Faculty Publications

Modern humans are characterized by a highly specialized foot that reflects our obligate bipedalism. Our understanding of hominin foot evolution is, although, hindered by a paucity of well-associated remains. Here we describe the foot of Homo naledi from Dinaledi Chamber, South Africa, using 107 pedal elements, including one nearly-complete adult foot. The H. naledi foot is predominantly modern human-like in morphology and inferred function, with an adducted hallux, an elongated tarsus, and derived ankle and calcaneocuboid joints. In combination, these features indicate a foot well adapted for striding bipedalism. However, the H. naledi foot differs from modern humans in having …


The Hand Of Homo Naledi, Tracy L. Kivell, Andrew S. Deane, Matthew W. Tocheri, Caley M. Orr, Peter Schmid, John Hawks, Lee R. Berger, Steven E. Churchill Oct 2015

The Hand Of Homo Naledi, Tracy L. Kivell, Andrew S. Deane, Matthew W. Tocheri, Caley M. Orr, Peter Schmid, John Hawks, Lee R. Berger, Steven E. Churchill

Neuroscience Faculty Publications

A nearly complete right hand of an adult hominin was recovered from the Rising Star cave system, South Africa. Based on associated hominin material, the bones of this hand are attributed to Homo naledi. This hand reveals a long, robust thumb and derived wrist morphology that is shared with Neandertals and modern humans, and considered adaptive for intensified manual manipulation. However, the finger bones are longer and more curved than in most australopiths, indicating frequent use of the hand during life for strong grasping during locomotor climbing and suspension. These markedly curved digits in combination with an otherwise human-like …


Distributed Encoding Of Spatial And Object Categories In Primate Hippocampal Microcircuits, Ioan Opris, Lucas M. Santos, Greg A. Gerhardt, Dong Song, Theodore W. Berger, Robert E. Hampson, Sam A. Deadwyler Oct 2015

Distributed Encoding Of Spatial And Object Categories In Primate Hippocampal Microcircuits, Ioan Opris, Lucas M. Santos, Greg A. Gerhardt, Dong Song, Theodore W. Berger, Robert E. Hampson, Sam A. Deadwyler

Neuroscience Faculty Publications

The primate hippocampus plays critical roles in the encoding, representation, categorization and retrieval of cognitive information. Such cognitive abilities may use the transformational input-output properties of hippocampal laminar microcircuitry to generate spatial representations and to categorize features of objects, images, and their numeric characteristics. Four nonhuman primates were trained in a delayed-match-to-sample (DMS) task while multi-neuron activity was simultaneously recorded from the CA1 and CA3 hippocampal cell fields. The results show differential encoding of spatial location and categorization of images presented as relevant stimuli in the task. Individual hippocampal cells encoded visual stimuli only on specific types of trials in …


Homo Naledi, A New Species Of The Genus Homo From The Dinaledi Chamber, South Africa, Lee R. Berger, John Hawks, Darryl J. De Ruiter, Steven E. Churchill, Peter Schmid, Lucas K. Delezene, Tracy L. Kivell, Heather M. Garvin, Scott A. Williams, Jeremy M. Desilva, Matthew M. Skinner, Charles M. Musiba, Noel Cameron, Trenton W. Holliday, William Harcourt-Smith, Rebecca R. Ackermann, Markus Bastir, Barry Bogin, Debra Bolter, Juliet Brophy, Zachary D. Cofran, Kimberly A. Congdon, Andrew S. Deane, Mana Dembo, Michelle Drapeau, Marina C. Elliott, Elen M. Feuerriegel, Daniel Garcia-Martinez, David J. Green, Alia Gurtov, Joel D. Irish, Ashley Kruger, Myra F. Laird, Damiano Marchi, Marc R. Meyer, Shahed Nalla, Enquye W. Negash, Caley M. Orr, Davorka Radovcic, Lauren Schroeder, Jill E. Scott, Zachary Throckmorton, Matthew W. Tocheri, Caroline Vansickle, Christopher S. Walker, Pianpian Wei, Bernhard Zipfel Sep 2015

Homo Naledi, A New Species Of The Genus Homo From The Dinaledi Chamber, South Africa, Lee R. Berger, John Hawks, Darryl J. De Ruiter, Steven E. Churchill, Peter Schmid, Lucas K. Delezene, Tracy L. Kivell, Heather M. Garvin, Scott A. Williams, Jeremy M. Desilva, Matthew M. Skinner, Charles M. Musiba, Noel Cameron, Trenton W. Holliday, William Harcourt-Smith, Rebecca R. Ackermann, Markus Bastir, Barry Bogin, Debra Bolter, Juliet Brophy, Zachary D. Cofran, Kimberly A. Congdon, Andrew S. Deane, Mana Dembo, Michelle Drapeau, Marina C. Elliott, Elen M. Feuerriegel, Daniel Garcia-Martinez, David J. Green, Alia Gurtov, Joel D. Irish, Ashley Kruger, Myra F. Laird, Damiano Marchi, Marc R. Meyer, Shahed Nalla, Enquye W. Negash, Caley M. Orr, Davorka Radovcic, Lauren Schroeder, Jill E. Scott, Zachary Throckmorton, Matthew W. Tocheri, Caroline Vansickle, Christopher S. Walker, Pianpian Wei, Bernhard Zipfel

Neuroscience Faculty Publications

Homo naledi is a previously-unknown species of extinct hominin discovered within the Dinaledi Chamber of the Rising Star cave system, Cradle of Humankind, South Africa. This species is characterized by body mass and stature similar to small-bodied human populations but a small endocranial volume similar to australopiths. Cranial morphology of H. naledi is unique, but most similar to early Homo species including Homo erectus, Homo habilis or Homo rudolfensis. While primitive, the dentition is generally small and simple in occlusal morphology. H. naledi has humanlike manipulatory adaptations of the hand and wrist. It also exhibits a humanlike foot …


Onset Time And Durability Of Huntingtin Suppression In Rhesus Putamen After Direct Infusion Of Antihuntingtin Sirna, Richard Grondin, Pei Ge, Qingmin Chen, Jessica E. Sutherland, Zhiming Zhang, Don M. Gash, David K. Stiles, Gregory R. Stewart, Dinah W. Y. Sah, William F. Kaemmerer Jun 2015

Onset Time And Durability Of Huntingtin Suppression In Rhesus Putamen After Direct Infusion Of Antihuntingtin Sirna, Richard Grondin, Pei Ge, Qingmin Chen, Jessica E. Sutherland, Zhiming Zhang, Don M. Gash, David K. Stiles, Gregory R. Stewart, Dinah W. Y. Sah, William F. Kaemmerer

Neuroscience Faculty Publications

One possible treatment for Huntington's disease involves direct infusion of a small, interfering RNA (siRNA) designed to reduce huntingtin expression into brain tissue from a chronically implanted programmable pump. Here, we studied the suppression of huntingtin mRNA achievable with short infusion times, and investigated how long suppression may persist after infusion ceases. Rhesus monkeys received 3 days of infusion of Magnevist into the putamen to confirm catheter patency and fluid distribution. After a 1-week washout period, monkeys received radiolabeled siRNA targeting huntingtin. After 1 or 3 days of siRNA delivery, monkeys were either terminated, or their pumps were shut off …


Neuron-Based Heredity And Human Evolution, Don M. Gash, Andrew S. Deane Jun 2015

Neuron-Based Heredity And Human Evolution, Don M. Gash, Andrew S. Deane

Neuroscience Faculty Publications

It is widely recognized that human evolution has been driven by two systems of heredity: one DNA-based and the other based on the transmission of behaviorally acquired information via nervous system functions. The genetic system is ancient, going back to the appearance of life on Earth. It is responsible for the evolutionary processes described by Darwin. By comparison, the nervous system is relatively newly minted and in its highest form, responsible for ideation and mind-to-mind transmission of information. Here the informational capabilities and functions of the two systems are compared. While employing quite different mechanisms for encoding, storing and transmission …


Disruption Of Columnar And Laminar Cognitive Processing In Primate Prefrontal Cortex Following Cocaine Exposure, Ioan Opris, Greg A. Gerhardt, Robert E. Hampson, Sam A. Deadwyler May 2015

Disruption Of Columnar And Laminar Cognitive Processing In Primate Prefrontal Cortex Following Cocaine Exposure, Ioan Opris, Greg A. Gerhardt, Robert E. Hampson, Sam A. Deadwyler

Neuroscience Faculty Publications

Prefrontal cortical activity in primate brain plays a critical role in cognitive processes involving working memory and the executive control of behavior. Groups of prefrontal cortical neurons within specified cortical layers along cortical minicolumns differentially generate inter- and intra-laminar firing to process relevant information for goal oriented behavior. However, it is not yet understood how cocaine modulates such differential firing in prefrontal cortical layers. Rhesus macaque nonhuman primates (NHPs) were trained in a visual delayed match-to-sample (DMS) task while the activity of prefrontal cortical neurons (areas 46, 8 and 6) was recorded simultaneously with a custom multielectrode array in cell …


Designer Receptors Enhance Memory In A Mouse Model Of Down Syndrome, Ashley M. Fortress, Eric D. Hamlett, Elena M. Vazey, Gary Aston-Jones, Wayne A. Cass, Heather A. Boger, Ann-Charlotte E. Granholm Jan 2015

Designer Receptors Enhance Memory In A Mouse Model Of Down Syndrome, Ashley M. Fortress, Eric D. Hamlett, Elena M. Vazey, Gary Aston-Jones, Wayne A. Cass, Heather A. Boger, Ann-Charlotte E. Granholm

Neuroscience Faculty Publications

Designer receptors exclusively activated by designer drugs (DREADDs) are novel and powerful tools to investigate discrete neuronal populations in the brain. We have used DREADDs to stimulate degenerating neurons in a Down syndrome (DS) model, Ts65Dn mice. Individuals with DS develop Alzheimer's disease (AD) neuropathology and have elevated risk for dementia starting in their 30s and 40s. Individuals with DS often exhibit working memory deficits coupled with degeneration of the locus coeruleus (LC) norepinephrine (NE) neurons. It is thought that LC degeneration precedes other AD-related neuronal loss, and LC noradrenergic integrity is important for executive function, working memory, and attention. …