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Poster Abstracts:
Two New Methods for Studying Serial Pattern
Learning in Rats. PDF
Karen E. Doyle & Stephen B. Fountain (Kent State
University)
In a serial multiple-choice (SMC) task like
Fountain & Rowan’s (1995), rats learned to choose successive correct
positions from a circular array of six nose poke receptacles on one
wall. Rats learning a structured pattern showed differential acquisition
rates for different elements types. When rats had to make a “start”
response for each trial on a receptacle centered in the circular array,
the same pattern of results was obtained. In a serial reaction time (SRT)
task in the same apparatus, rats learned to track the shifting position
of a light presented as either a structured or unstructured series.
Although the groups made similar chunk-boundary and within-chunk errors,
rats learned to make fewer errors on a violation element in the
structured series compared to the comparable item in the unstructured
series. Differences between results from the SMC and SRT procedures
will be discussed.
Rats Abstract Rules from a Response Series Lacking
a Consistent Motor Sequence. PDF
Shannon M. A. Kundey (Hood College) & Stephen B.
Fountain (Kent State University)
Research shows rats can learn rule-based response
sequences by pressing levers in a circular array according to a
consistent motor pattern. Learning a sequence under these conditions
does not necessarily require rats to learn abstract rules; rats can
potentially learn such sequences via simpler associative motor learning
processes. We explored rats’ sequence learning when they could not
succeed by repeating a set motor sequence. Rats learned either a
structured (12345678) or an unstructured (17356428) subpattern
interleaved with responses on randomly presented levers (X):
1X2X3X4X5X6X7X8X or 1X7X3X5X6X4X2X8X, respectively. Only rats in the
structured group learned their pattern. Sequential structure in
nonadjacent elements mediated superior pattern learning even when the
rule relating those elements could not be abstracted from a set motor
pattern.
Adolescent Nicotine Exposure Procedures and Adult
Rat Serial Pattern Learning. PDF
Laura R. G. Pickens & Stephen B. Fountain (Kent
State University)
Adolescent nicotine exposure via osmotic pump at 6
mg/kg/day over postnatal days (P) 30-48 produces neurophysiological
changes in the brains of adult rats (Trauth et al., 1999). We examined
whether nicotine delivered in this manner during adolescence would
produce cognitive deficits like those seen after daily injections in a
study by Fountain et al. (2008). After adolescent exposure via the
osmotic pump method, adult rats learned serial patterns beginning on P95
in the cognitive task of Fountain et al. (2008). Whereas Fountain et al.
(2008) found that daily nicotine injections of 1 mg/kg over P25-59
caused impairments in adult rat serial pattern learning, adolescent
exposure via osmotic pump did not produce cognitive deficits in adult
rats. We will compare these two studies that used the same cognitive
paradigm and propose possible reasons for the differing results.
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