Neuroscience 2002 Abstract
| Presentation Number: | 280.9 |
|---|---|
| Abstract Title: | Feedforward vs recurrent inhibition regulating dopamine effects on the working memory field formation of prefrontal cortical neurons. |
| Authors: |
Tanaka, S.*1
; Yamashita, K.1
1Dept of Electrical Engin, Sophia Univ, Tokyo, Japan |
| Primary Theme and Topics |
Cognition and Behavior - Animal Cognition and Behavior -- Cognitive learning and memory systems |
| Secondary Theme and Topics | Cognition and Behavior<br />- Animal Cognition and Behavior<br />-- Learning & memory: Physiology and imaging |
| Session: |
280. Animal cognition and behavior: learning and memory--physiology and imaging: reward and motivation Poster |
| Presentation Time: | Monday, November 4, 2002 8:00 AM-9:00 AM |
| Location: | Hall A2-B3 N-22 |
| Keywords: | delay period, prefrontal cortex, sustained activity, NMDA |
Computer simulation recently suggested that the prefrontal cortical circuit can perform fundamental cognitive operations of multi-target spatial working memory (Tanaka 2001 SFN #852.1, 2002a, b). The operations contain replacement, addition, rejection, and elimination. Moreover, slight deviation of the prefrontal cortical dopamine level in the normal range can switch these operations (Tanaka 2001, 2002a, b). The results suggest the involvement of dopamine in the oprations of multi-target spatial working memory.
When the prefrontal cortical dopamine level is outside of the normal range, proper memory fields are not formed in the cortical neurons (Williams et al. 1995; Goldman-Rakic 2000; Yamashita and Tanaka 2002). This paper addresses how the wide change in the dopamine level affects the signal flow in the prefrontal cortical circuit by computer simulation of a circuit model.
In the supraoptimal range of the dopamine level, inhibition in the circuit works effectively. But the circuit mechanisms of the inhibition depends on how much degree the AMPA-channel synaptic transmission is decreased with the D1R activation level. If the decrement of the AMPA transmission is slight, as reported by Seamans et al. (2001), feedforward inhibition is dominant. On the contrary, if it is stronger, as reported by Gao et al. (2001), recurrent inhibition works more strongly than feedforward inhibition. The simulation predicts that the background activity of the prefrontal interneuorns increases [or decreases] with the dopamine level in the former case [or the latter case, respectively].
When the prefrontal cortical dopamine level is outside of the normal range, proper memory fields are not formed in the cortical neurons (Williams et al. 1995; Goldman-Rakic 2000; Yamashita and Tanaka 2002). This paper addresses how the wide change in the dopamine level affects the signal flow in the prefrontal cortical circuit by computer simulation of a circuit model.
In the supraoptimal range of the dopamine level, inhibition in the circuit works effectively. But the circuit mechanisms of the inhibition depends on how much degree the AMPA-channel synaptic transmission is decreased with the D1R activation level. If the decrement of the AMPA transmission is slight, as reported by Seamans et al. (2001), feedforward inhibition is dominant. On the contrary, if it is stronger, as reported by Gao et al. (2001), recurrent inhibition works more strongly than feedforward inhibition. The simulation predicts that the background activity of the prefrontal interneuorns increases [or decreases] with the dopamine level in the former case [or the latter case, respectively].
Supported by The Ministry of Education, Science and Technology grants #13210123 and #14017083.
Sample Citation:
[Authors]. [Abstract Title]. Program No. XXX.XX. 2002 Neuroscience Meeting Planner. Orlando, FL: Society for Neuroscience, 2002. Online.
Copyright © 2002-2026 Society for Neuroscience; all rights reserved. Permission to republish any abstract or part of any abstract in any form must be obtained in writing by SfN office prior to publication.
