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Social and Behavioral Sciences Commons™
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Articles 1 - 8 of 8
Full-Text Articles in Social and Behavioral Sciences
Neurogenesis-Mediated Forgetting Minimizes Proactive Interference., Jonathan R Epp, Rudy Silva Mera, Stefan Köhler, Sheena A Josselyn, Paul W Frankland
Neurogenesis-Mediated Forgetting Minimizes Proactive Interference., Jonathan R Epp, Rudy Silva Mera, Stefan Köhler, Sheena A Josselyn, Paul W Frankland
Brain and Mind Institute Researchers' Publications
Established memories may interfere with the encoding of new memories, particularly when existing and new memories overlap in content. By manipulating levels of hippocampal neurogenesis, here we show that neurogenesis regulates this form of proactive interference. Increasing hippocampal neurogenesis weakens existing memories and, in doing so, facilitates the encoding of new, conflicting (but not non-conflicting) information in mice. Conversely, decreasing neurogenesis stabilizes existing memories, and impedes the encoding of new, conflicting information. These results suggest that reduced proactive interference is an adaptive benefit of neurogenesis-induced forgetting.
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
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.
Running Enhances Spatial Pattern Separation In Mice., David J Creer, Carola Romberg, Lisa M Saksida, Henriette Van Praag, Timothy J Bussey
Running Enhances Spatial Pattern Separation In Mice., David J Creer, Carola Romberg, Lisa M Saksida, Henriette Van Praag, Timothy J Bussey
Brain and Mind Institute Researchers' Publications
Increasing evidence suggests that regular exercise improves brain health and promotes synaptic plasticity and hippocampal neurogenesis. Exercise improves learning, but specific mechanisms of information processing influenced by physical activity are unknown. Here, we report that voluntary running enhanced the ability of adult (3 months old) male C57BL/6 mice to discriminate between the locations of two adjacent identical stimuli. Improved spatial pattern separation in adult runners was tightly correlated with increased neurogenesis. In contrast, very aged (22 months old) mice had impaired spatial discrimination and low basal cell genesis that was refractory to running. These findings suggest that the addition of …
Adapting To Dynamic Stimulus-Response Values: Differential Contributions Of Inferior Frontal, Dorsomedial, And Dorsolateral Regions Of Prefrontal Cortex To Decision Making., Derek G V Mitchell, Qian Luo, Shelley B Avny, Tomasz Kasprzycki, Karanvir Gupta, Gang Chen, Elizabeth C Finger, R James R Blair
Adapting To Dynamic Stimulus-Response Values: Differential Contributions Of Inferior Frontal, Dorsomedial, And Dorsolateral Regions Of Prefrontal Cortex To Decision Making., Derek G V Mitchell, Qian Luo, Shelley B Avny, Tomasz Kasprzycki, Karanvir Gupta, Gang Chen, Elizabeth C Finger, R James R Blair
Brain and Mind Institute Researchers' Publications
Dorsomedial prefrontal cortex (dmPFC), dorsolateral prefrontal cortex (dlPFC), and inferior frontal gyrus (IFG) have all been implicated in resolving decision conflict whether this conflict is generated by having to select between responses of similar value or by making selections following a reversal in reinforcement contingencies. However, work distinguishing their individual functional contributions remains preliminary. We used functional magnetic resonance imaging to delineate the functional role of these systems with regard to both forms of decision conflict. Within dmPFC and dlPFC, blood oxygen level-dependent responses increased in response to decision conflict regardless of whether the conflict occurred in the context of …
Glutamate Receptors In Perirhinal Cortex Mediate Encoding, Retrieval, And Consolidation Of Object Recognition Memory., Boyer D Winters, Timothy J Bussey
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 …
Functionally Dissociating Aspects Of Event Memory: The Effects Of Combined Perirhinal And Postrhinal Cortex Lesions On Object And Place Memory In The Rat., T J Bussey, J L Muir, J P Aggleton
Functionally Dissociating Aspects Of Event Memory: The Effects Of Combined Perirhinal And Postrhinal Cortex Lesions On Object And Place Memory In The Rat., T J Bussey, J L Muir, J P Aggleton
Brain and Mind Institute Researchers' Publications
Reciprocal interactions between the hippocampus and the perirhinal and parahippocampal cortices form core components of a proposed temporal lobe memory system. For this reason, the involvement of the hippocampus in event memory is thought to depend on its connections with these cortical areas. Contrary to these predictions, we found that NMDA-induced lesions of the putative rat homologs of these cortical areas (perirhinal plus postrhinal cortices) did not impair performance on two allocentric spatial tasks highly sensitive to hippocampal dysfunction. Remarkably, for one of the tasks there was evidence of a facilitation of performance. The same cortical lesions did, however, disrupt …
Fornix Lesions Can Facilitate Acquisition Of The Transverse Patterning Task: A Challenge For "Configural" Theories Of Hippocampal Function., T J Bussey, E Clea Warburton, J P Aggleton, J L Muir
Fornix Lesions Can Facilitate Acquisition Of The Transverse Patterning Task: A Challenge For "Configural" Theories Of Hippocampal Function., T J Bussey, E Clea Warburton, J P Aggleton, J L Muir
Brain and Mind Institute Researchers' Publications
Configural theories of hippocampal function predict that hippocampal dysfunction should impair acquisition of the transverse patterning task, which involves the concurrent solution of three discrimination problems: A+ versus B-; B+ versus C-; and C+ versus A-. The present study tested this prediction in rats using computer-graphic stimuli presented on a touchscreen. Experiment 1 assessed the effects of fornix lesions when the three problems were introduced sequentially (phase 1: A+ vs B-; phase 2: A+ vs B-, B+ vs C-; phase 3: A+ vs B-, B+ vs C-, C+ vs A-). Fornix lesions significantly facilitated acquisition of the complete transverse patterning …
Triple Dissociation Of Anterior Cingulate, Posterior Cingulate, And Medial Frontal Cortices On Visual Discrimination Tasks Using A Touchscreen Testing Procedure For The Rat., T J Bussey, J L Muir, B J Everitt, T W Robbins
Triple Dissociation Of Anterior Cingulate, Posterior Cingulate, And Medial Frontal Cortices On Visual Discrimination Tasks Using A Touchscreen Testing Procedure For The Rat., T J Bussey, J L Muir, B J Everitt, T W Robbins
Brain and Mind Institute Researchers' Publications
Four experiments examined effects of quinolinic acid-induced lesions of the anterior cingulate, posterior cingulate, and medial frontal cortices on tests of visual discrimination learning, using a new "touchscreen" testing method for rats. Anterior cingulate cortex lesions impaired acquisition of an 8-pair concurrent discrimination task, whereas posterior cingulate cortex lesions facilitated learning but selectively impaired the late stages of acquisition of a visuospatial conditional discrimination. Medial frontal cortex lesions selectively impaired reversal learning when stimuli were difficult to discriminate; lesions of anterior and posterior cingulate cortex had no effect. These results suggest roles for the anterior cingulate, posterior cingulate, and medial …