TY - JOUR
T1 - Between-session memory degradation accounts for within-session changes in fixed-interval performance
AU - Daniels, Carter W.
AU - Overby, Paula F.
AU - Sanabria, Federico
N1 - Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2018/8
Y1 - 2018/8
N2 - A common assumption in the study of fixed-interval (FI) timing is that FI performance is largely stable within sessions, once it is stable between sessions. Within-session changes in FI performance were examined in published data (Daniels and Sanabria, 2017), wherein some rats were trained on a FI 30-s schedule of food reinforcement (FI30) and others on a FI 90-s schedule (FI90). Following stability, FI90 rats were pre-fed for five sessions. Response rates declined as a function of trial, due more to latency lengthening than to run-rate reduction. Latencies were best described by a dynamic gamma-exponential mixture distribution, in which latency lengthening was driven by the growth of the criterion pulse count for a response and not by a reduction in the speed of an endogenous clock. The speed of the clock was selectively sensitive to the length of the FI; the prevalence and length of exponentially-distributed latencies were selectively sensitive to pre-feeding. These findings reveal (a) that parameters governing FI latencies are selectively sensitive to a range of manipulations, (b) a potential degradation of the criterion pulse count between consecutive sessions, and (c) a subsequent recovery of the criterion pulse count within sessions.
AB - A common assumption in the study of fixed-interval (FI) timing is that FI performance is largely stable within sessions, once it is stable between sessions. Within-session changes in FI performance were examined in published data (Daniels and Sanabria, 2017), wherein some rats were trained on a FI 30-s schedule of food reinforcement (FI30) and others on a FI 90-s schedule (FI90). Following stability, FI90 rats were pre-fed for five sessions. Response rates declined as a function of trial, due more to latency lengthening than to run-rate reduction. Latencies were best described by a dynamic gamma-exponential mixture distribution, in which latency lengthening was driven by the growth of the criterion pulse count for a response and not by a reduction in the speed of an endogenous clock. The speed of the clock was selectively sensitive to the length of the FI; the prevalence and length of exponentially-distributed latencies were selectively sensitive to pre-feeding. These findings reveal (a) that parameters governing FI latencies are selectively sensitive to a range of manipulations, (b) a potential degradation of the criterion pulse count between consecutive sessions, and (c) a subsequent recovery of the criterion pulse count within sessions.
KW - Computational modeling
KW - Fixed-interval schedule of reinforcement
KW - Interval timing
KW - Rats
KW - Response threshold
KW - Within-session
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UR - http://www.scopus.com/inward/citedby.url?scp=85047157287&partnerID=8YFLogxK
U2 - 10.1016/j.beproc.2018.05.004
DO - 10.1016/j.beproc.2018.05.004
M3 - Article
C2 - 29729953
AN - SCOPUS:85047157287
SN - 0376-6357
VL - 153
SP - 31
EP - 39
JO - Behavioural processes
JF - Behavioural processes
ER -