Program#/Poster#: |
834.11 |
Title: |
Temporal dynamics in
coherent delta and theta oscillations within the amygdalo-prefronto-striatal
network as correlates of interval timing in rats |
Location: |
387 |
Presentation Time: |
Wednesday, Oct 17, 2012,
3:30 PM - 3:45 PM |
Authors: |
*J. KNIPPENBERG1,2,
M. GRAUPNER3, L. DIAZ-MATAIX3, J. LEDOUX3,4,
V. DOYERE1,2,3;
1UMR 8195, Ctr. De Neurosciences Paris-Sud, Orsay, France; 2CNRS,
Orsay, France; 3Ctr. for Neural Sci., New York, NY; 4Emotional
Brain Inst., Nathan S. Kline Inst. for Psychiatry Res., Orangeburg, NY |
Abstract: |
Humans and animals have
the capacity to estimate durations ranging from seconds to minutes, a cognitive
ability named interval timing. Neural structures traditionally implicated
in interval timing are the medial prefrontal cortex (mPFC) and dorsal striatum.
Findings from our labs have shown that the amygdala is involved in responding
to changes in the timing of shocks in Pavlovian fear conditioning. Despite
this anatomical delimitation, relatively little is known about the neurophysiological
processes within these structures that ultimately mediate interval timing.
Here, we sought to indentify neurophysiological correlates within the mPFC,
dorsal striatum and basal amygdala using a modified fear conditioning procedure
in rats, in which two different auditory tones served as conditioned stimuli
(CS, 1 or 11 kHz, each 60-s long) signalling two different arrival times
(at 10 or 30 s during the CS) of a footshock unconditioned stimulus (US).
Rats were food deprived and trained to press a lever to obtain occasional
food rewards. During fear conditioning CS-US pairings as well as CSs alone
(probe trials) were presented independent of ongoing lever pressing activity
and the food reinforcement schedule. Conditioned suppression of lever pressing
during the 60-s CS probe trials demonstrated a temporal pattern of US anticipation
with a peak before the time of US delivery. After stable temporal behavior
was acquired rats were implanted with electrodes aimed at mPFC, dorsal striatum
and basal amygdala. Then, local field potential (LFP) recordings were obtained
as rats were again subjected to the conditioning protocol. Probe trials
were used for LFP analysis. The power spectral density of the entire 60-s
CS epoch contained two dominant frequency bands: a delta (1-4 Hz) and theta
(5-8 Hz) rhythm. Coherence between pairs of recorded structures showed timing-related
changes within the theta band, and to a lesser extent also within the delta
band. As the mPFC, dorsal striatum and basal amygdala are anatomically interconnected,
these initial results might point to a role of theta and delta oscillations
within an amygdalo-prefronto-striatal network in encoding the timing of
biological significant events and/or the mediation of temporal behavior.
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Support: |
ANR Memotime |
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ANR TDE |
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LIA Emotime |
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PUF Emotion & Timing |
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