Psychology Commons^™

Specific Contributions Of Ventromedial, Anterior Cingulate, And Lateral Prefrontal Cortex For Attentional Selection And Stimulus Valuation., Daniel Kaping, Martin Vinck, R Matthew Hutchison, Stefan Everling, Thilo Womelsdorf

Brain and Mind Institute Researchers' Publications

Attentional control ensures that neuronal processes prioritize the most relevant stimulus in a given environment. Controlling which stimulus is attended thus originates from neurons encoding the relevance of stimuli, i.e. their expected value, in hand with neurons encoding contextual information about stimulus locations, features, and rules that guide the conditional allocation of attention. Here, we examined how these distinct processes are encoded and integrated in macaque prefrontal cortex (PFC) by mapping their functional topographies at the time of attentional stimulus selection. We find confined clusters of neurons in ventromedial PFC (vmPFC) that predominantly convey stimulus valuation information during attention shifts. …

Development Of A Cohesion Inventory For Children's Sport Teams, Luc J. Martin

Electronic Thesis and Dissertation Repository

The general purpose of this dissertation was to develop an inventory designed to measure cohesion in children’s (ages 9-12) sport teams. To this end, three studies were conducted. In Study 1, children became active agents in the process of test construction. More specifically, children (N = 167) participated in focus groups and completed open-ended questionnaires in order to provide information on their perceptions of cohesion as well as motives for participating, continuing, and ceasing involvement on sport teams. Study 2 involved the use of the information obtained from Study 1 to develop potential items for the questionnaire. In addition, the …

Paradoxical Reversal Learning Enhancement By Stress Or Prefrontal Cortical Damage: Rescue With Bdnf., Carolyn Graybeal, Michael Feyder, Emily Schulman, Lisa M Saksida, Timothy J Bussey, Jonathan L Brigman, Andrew Holmes

Brain and Mind Institute Researchers' Publications

Stress affects various forms of cognition. We found that moderate stress enhanced late reversal learning in a mouse touchscreen-based choice task. Ventromedial prefrontal cortex (vmPFC) lesions mimicked the effect of stress, whereas orbitofrontal and dorsolateral striatal lesions impaired reversal. Stress facilitation of reversal was prevented by BDNF infusion into the vmPFC. These findings suggest a mechanism by which stress-induced vmPFC dysfunction disinhibits learning by alternate (for example, striatal) systems.

Principles Of Sensorimotor Learning., Daniel M Wolpert, Jörn Diedrichsen, J Randall Flanagan

Brain and Mind Institute Researchers' Publications

The exploits of Martina Navratilova and Roger Federer represent the pinnacle of motor learning. However, when considering the range and complexity of the processes that are involved in motor learning, even the mere mortals among us exhibit abilities that are impressive. We exercise these abilities when taking up new activities - whether it is snowboarding or ballroom dancing - but also engage in substantial motor learning on a daily basis as we adapt to changes in our environment, manipulate new objects and refine existing skills. Here we review recent research in human motor learning with an emphasis on the computational …

The Levels Of Analysis Revisited., Scott A Macdougall-Shackleton

Brain and Mind Institute Researchers' Publications

The term levels of analysis has been used in several ways: to distinguish between ultimate and proximate levels, to categorize different kinds of research questions and to differentiate levels of reductionism. Because questions regarding ultimate function and proximate mechanisms are logically distinct, I suggest that distinguishing between these two levels is the best use of the term. Integrating across levels in research has potential risks, but many benefits. Consideration at one level can help generate novel hypotheses at the other, define categories of behaviour and set criteria that must be addressed. Taking an adaptationist stance thus strengthens research on proximate …

The Importance Of Self-Efficacy And Basic Psychological Needs In Children’S Physical Activity: Measurement, Prediction And Intervention, Casey E. Gray

Electronic Thesis and Dissertation Repository

The importance of physical activity in the overall health promotion and primary prevention of cardiovascular disease risk factors and metabolic diseases in children is well established. Nonetheless, interventions to increase physical activity among this population have been largely unsuccessful. The main objective of the research in this dissertation was to explore the suitability of self-efficacy and basic psychological needs for physical activity prediction and intervention in children. Item generation and psychometric evaluation of psychological questionnaires occurred in study 1 (Chapter 2). Using a prospective design, study 2 (Chapter 3) established task efficacy, barriers efficacy, competence, and autonomy as significant predictors …

Prefrontal Cortex Deactivation In Macaques Alters Activity In The Superior Colliculus And Impairs Voluntary Control Of Saccades, Michael J. Koval, Stephen G. Lombar, Stefan Everling

Brain and Mind Institute Researchers' Publications

The cognitive control of action requires both the suppression of automatic responses to sudden stimuli and the generation of behavior specified by abstract instructions. Though patient, functional imaging and neurophysiological studies have implicated the dorsolateral prefrontal cortex (dlPFC) in these abilities, the mechanism by which the dlPFC exerts this control remains unknown. Here we examined the functional interaction of the dlPFC with the saccade circuitry by deactivating area 46 of the dlPFC and measuring its effects on the activity of single superior colliculus neurons in monkeys performing a cognitive saccade task. Deactivation of the dlPFC reduced preparatory activity and increased …

The Effect Of Dopamine Therapy On Ventral And Dorsal Striatum-Mediated Cognition In Parkinson's Disease: Support From Functional Mri., Penny A Macdonald, Alex A Macdonald, Ken N Seergobin, Ruzbeh Tamjeedi, Hooman Ganjavi, Jean-Sebastien Provost, Oury Monchi

Brain and Mind Institute Researchers' Publications

The central aim of our study was to elucidate functions mediated by the ventral and dorsal striatum, respectively, to better understand the cognitive effects of dopamine replacement in Parkinson's disease. We proposed that the ventral striatum underlies general learning of stimulus associations, whereas the dorsal striatum promotes integration of various influences on selecting. In Parkinson's disease, dopamine depletion is substantially less notable in the ventral relative to the dorsal striatum, and therefore greater improvements are expected for dorsal striatum-mediated functions with dopamine replacement. Using a simple selection task, we found that dopamine replacement impaired encoding and facilitation of consistent stimulus-stimulus …

Differential Effects Of Dopaminergic Therapies On Dorsal And Ventral Striatum In Parkinson's Disease: Implications For Cognitive Function., Penny A Macdonald, Oury Monchi

Brain and Mind Institute Researchers' Publications

Cognitive abnormalities are a feature of Parkinson's disease (PD). Unlike motor symptoms that are clearly improved by dopaminergic therapy, the effect of dopamine replacement on cognition seems paradoxical. Some cognitive functions are improved whereas others are unaltered or even hindered. Our aim was to understand the effect of dopamine replacement therapy on various aspects of cognition. Whereas dorsal striatum receives dopamine input from the substantia nigra (SN), ventral striatum is innervated by dopamine-producing cells in the ventral tegmental area (VTA). In PD, degeneration of SN is substantially greater than cell loss in VTA and hence dopamine-deficiency is significantly greater in …

Learning From Mistakes: Improving Initial Fingertip Force Scaling By Observing Lifting Errors, Gavin Buckingham, Minnie Tang, Paul Gribble, Melvyn A. Goodale

Psychology Presentations

• When lifting objects that are lighter or heaver than we expect them to be, individuals typically misapply forces in a way that reflects their prior expectations of heaviness.

• Because we lift in this predictive way, large and small cubes elicit these characteristic errors even when they are adjusted to have equal mass. Lifters will apply too much force to a large cube and substantially less force to a small cube – errors that are rapidly corrected with repeated lifts (Flanagan & Beltzner, 2000).

• When watching others lift objects, an observer’s motor system automatically reacts in a way …

Negative Associations Between Corpus Callosum Midsagittal Area And Iq In A Representative Sample Of Healthy Children And Adolescents., Hooman Ganjavi, John D Lewis, Pierre Bellec, Penny A Macdonald, Deborah P Waber, Alan C Evans, Sherif Karama, The Brain Development Cooperative Group

Brain and Mind Institute Researchers' Publications

Documented associations between corpus callosum size and cognitive ability have heretofore been inconsistent potentially owing to differences in sample characteristics, differing methodologies in measuring CC size, or the use of absolute versus relative measures. We investigated the relationship between CC size and intelligence quotient (IQ) in the NIH MRI Study of Normal Brain Development sample, a large cohort of healthy children and adolescents (aged six to 18, n = 198) recruited to be representative of the US population. CC midsagittal area was measured using an automated system that partitioned the CC into 25 subregions. IQ was measured using the Wechsler …