Functional Stability and Learning in the Dorsolateral Prefrontal Cortex

Persistent Link:
http://hdl.handle.net/10150/195923
Title:
Functional Stability and Learning in the Dorsolateral Prefrontal Cortex
Author:
Greenberg, Paul Arthur
Issue Date:
2005
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
"Stable multi-day recordings from chronically implanted microelectrodes within the dorsolateral prefrontal cortex of two monkeys performing three Go/NoGo visual discrimination tasks (one requiring well-learned responses, two requiring learning) demonstrated that the majority of prefrontal neurons were 'functionally stable'. Action potentials of 94 neurons were stable over 2-9 days; 66/94 (70%) of these cells responded each day, 22/94 (23%) never responded significantly, and 6/94 (6%) responded one day but not the next. Of 66 responsive neurons, 55 were selective for either Go or NoGo trials, individual stimuli, or eye movements." (Greenberg and Wilson, 2004) Selectivity was maintained, for 46/55 neurons across all recording days. Response strength (baseline vs. post-stimulation firing rates) and event-related response timing also displayed stability. Stability generalized across neuronal response type suggesting that functional stability is a general property. Long-term recordings from other studies supported similar conclusions suggesting that neurons throughout the brain are functionally stable. Single-day recordings from different neurons within the same cortical regions demonstrated neuronal response flexibility while monkeys learned associations among visual cues, and Go/NoGo behavioral responses. Of 116 neurons, 57 (49%) displayed significant change points in firing rates during novel learning (n=18), reversal learning (n=12), or both tasks (n=27). Six of 57(10.5%) neurons had firing rates changes prior to learning and might have been causally related to the monkeys' behavioral changes. However, only 18/152 (12%) of the total number of firing rate changes occurred prior to the monkeys' learning meaning that most appeared to be the consequences of learning rather than the causes.
Type:
text; Electronic Dissertation
Keywords:
Functional Stability; Visual Discrimination Learning; Prefrontal Cortex; Single Neuron
Degree Name:
PhD
Degree Level:
doctoral
Degree Program:
Psychology; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
Ryan, Lee T.

Full metadata record

DC FieldValue Language
dc.language.isoENen_US
dc.titleFunctional Stability and Learning in the Dorsolateral Prefrontal Cortexen_US
dc.creatorGreenberg, Paul Arthuren_US
dc.contributor.authorGreenberg, Paul Arthuren_US
dc.date.issued2005en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstract"Stable multi-day recordings from chronically implanted microelectrodes within the dorsolateral prefrontal cortex of two monkeys performing three Go/NoGo visual discrimination tasks (one requiring well-learned responses, two requiring learning) demonstrated that the majority of prefrontal neurons were 'functionally stable'. Action potentials of 94 neurons were stable over 2-9 days; 66/94 (70%) of these cells responded each day, 22/94 (23%) never responded significantly, and 6/94 (6%) responded one day but not the next. Of 66 responsive neurons, 55 were selective for either Go or NoGo trials, individual stimuli, or eye movements." (Greenberg and Wilson, 2004) Selectivity was maintained, for 46/55 neurons across all recording days. Response strength (baseline vs. post-stimulation firing rates) and event-related response timing also displayed stability. Stability generalized across neuronal response type suggesting that functional stability is a general property. Long-term recordings from other studies supported similar conclusions suggesting that neurons throughout the brain are functionally stable. Single-day recordings from different neurons within the same cortical regions demonstrated neuronal response flexibility while monkeys learned associations among visual cues, and Go/NoGo behavioral responses. Of 116 neurons, 57 (49%) displayed significant change points in firing rates during novel learning (n=18), reversal learning (n=12), or both tasks (n=27). Six of 57(10.5%) neurons had firing rates changes prior to learning and might have been causally related to the monkeys' behavioral changes. However, only 18/152 (12%) of the total number of firing rate changes occurred prior to the monkeys' learning meaning that most appeared to be the consequences of learning rather than the causes.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectFunctional Stabilityen_US
dc.subjectVisual Discrimination Learningen_US
dc.subjectPrefrontal Cortexen_US
dc.subjectSingle Neuronen_US
thesis.degree.namePhDen_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplinePsychologyen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairRyan, Lee T.en_US
dc.contributor.committeememberFuglevand, Andrewen_US
dc.contributor.committeememberMcMullen, Nateen_US
dc.contributor.committeememberJacobs, Jakeen_US
dc.identifier.proquest1030en_US
dc.identifier.oclc137353588en_US
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