S1 (FriAM 1-65) - The Psychonomic Society

Saturday Morning Papers 138–143
This is an interesting result because feedback entailed repetition of the
item. Our experiment examines the reliability of this result as a function
of delay of second test and contrasts immediate feedback with delayed
feedback on the premise that delayed feedback is analogous to
spaced repetition. Perhaps immediate feedback’s ineffectiveness is the
result of massed repetition. To the contrary, all combinations of feedback
timing and second test delay replicated Pashler et al.’s result for
initially correct responses. The data also contained a potentially important
new result in the form of exaggerated rates of commission errors
following immediate feedback. This finding is important because
virtually every study of feedback reports significant perseveration of
initial commission errors onto later tests.
9:00–9:15 (138)
Working Memory Load Boosts Learning in a Blocking Paradigm: An
fMRI Study. CHRISTIAN C. LUHMANN, NICHOLAS B. TURK-
BROWNE, & MARVIN M. CHUN, Yale University—Blocking is a
classic phenomenon in which learning is suppressed when events are
completely predictable. Associative learning theory explains blocking
(and other forms of learning) by relying on prediction error. However,
critics of associative theory have demonstrated that performing a difficult
secondary task during learning attenuates blocking, suggesting
that blocking stems from nonassociative processes. The present fMRI
experiment sought to evaluate these accounts of blocking. Subjects
completed two runs of a learning task, one with load and one without.
Behaviorally, blocking was only observed under no load. Activity in
right prefrontal cortex also exhibited a blocking effect under no load.
Like behavior, the neural blocking effect in this region was significantly
reduced under load. Activity in this region also conformed to
a variety of additional predictions from associative learning theory.
These results suggest that working memory load actually increases the
amount of learning during blocking, supporting an associative account.
9:20–9:35 (139)
Selective Attention and Blocking in Human Learning. MARK B.
SURET, MIKE E. LE PELLEY, & THOMAS BEESLEY, Cardiff University
(sponsored by Mark E. Bouton)—Blocking refers to the finding
that learning about the relationship between a cue and an outcome
is reduced if that cue is trained in compound with a second cue that
has been previously established as a reliable predictor of the outcome.
It has previously been proposed that blocking reflects a reduction in
the amount of attention paid to the blocked cue. We present evidence
from a study of human learning that is consistent with this suggestion.
However, in this experiment (as in all others looking at attentional effects
in human learning) the relative predictiveness of the cues involved
is confounded with differences in their absolute associative
strength. A second experiment deconfounds these variables; results
indicate that it is absolute strength, rather than relative predictiveness,
that is the crucial determinant of stimulus processing. These results
provide a challenge to the prevailing view of the operation of selective
attention in learning.
9:40–9:55 (140)
Associative Learning and Stereotype Formation: The Influence of
Learned Predictiveness. MIKE E. LE PELLEY, Cardiff University,
STIAN J. REIMERS, University College London, & GUGLIELMO
CALVINI, Cardiff University—Stereotypes are beliefs about traits
that are shared by members of a social group. Stereotype formation is
complicated by the fact that target individuals belong to several
groups simultaneously (by gender, age, race, etc.). Hence, stereotype
formation can be seen as a categorization problem, in which people
learn to associate certain category features (but not others) with traits.
What, then, determines the extent to which a given category feature
supports stereotype formation? One possibility (deriving from studies
of animal conditioning) is that biases in stereotype formation reflect
the operation of associative mechanisms allowing for changes in
the “associability” of cues as a consequence of differences in their
prior predictiveness. We demonstrate that this is indeed the case. In
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more general terms, our results indicate that an appreciation of the
mechanisms underlying animal conditioning and associative learning
can aid our understanding of relatively complex examples of human
learning and behavior.
10:00–10:15 (141)
Group Predictiveness Bias in Social Stereotype Formation and Expression:
Bias in Group Associability or Simple Response Strength
Effect? GUGLIELMO CALVINI & MIKE E. LE PELLEY, Cardiff
University, & STIAN J. REIMERS, University College London—
Mechanisms of associative learning appear to govern the ability to attribute
traits and behavioral dispositions to social categories and to
form social stereotypes. Furthermore, the predictive history of social
categories seems to determine the strength of such stereotypic associations.
Learning that membership of a group reliably predicts neutral
events determines the strength of positive or negative beliefs subsequently
formed about the group. However, group predictiveness
might also affect the strength of evaluative responses elicited by group
membership. To test such hypothesis, a series of experiments was conducted
whereby participants experienced group predictiveness after
forming an evaluation of the group’s behavior. The results indicate
that learning that a social group is a poor predictor after forming a
strong evaluation does not moderate evaluative responses to the
group. This confirms that group predictiveness only biases the formation
of stereotypic associations, whereas it does not affect the
strength of the responses to the group.
Recall Processes
Beacon A, Saturday Morning, 8:00–10:00
Chaired by Steven M. Smith, Texas A&M University
8:00–8:15 (142)
Context Fluctuation and Time-Dependent Memory Phenomena.
STEVEN M. SMITH, Texas A&M University—Why do memory phenomena
such as long-term recency, reminiscence, expanding retrieval
practice effects, and spacing of repetitions effects depend upon temporal
parameters? Estes (1955) said, “. . . an unfilled temporal interval
never remains permanently satisfying as an explanatory variable,”
and he suggested that statistical properties of random environmental
events during temporal intervals (what some have referred to as “contextual
fluctuation”) can explain many such effects. Can contextual
fluctuation be experimentally manipulated? The results of a powerful
manipulation of environmental context effects, operationally defined
as background movie scenes for stimulus words, indicate strong effects
of context reinstatement on recall. Context fluctuation was manipulated,
holding time constant, by showing many changing movie
scenes versus showing one long relatively constant scene. Effects of
faster scene changes (i.e., more context fluctuation) resembled effects
of longer time intervals on long-term recency.
8:20–8:35 (143)
The Interaction of Task Context and Temporal Context in Free
Recall. SEAN M. POLYN, University of Pennsylvania, KENNETH A.
NORMAN, Princeton University, & MICHAEL J. KAHANA, University
of Pennsylvania—The principle of encoding specificity states
that memory retrieval will be most successful when the memory cues
available at retrieval match those present at study. Here, we investigate
the ability of the memory system to alter the set of available cues
on the fly during the search process, by retrieving and maintaining
contextual details associated with the studied items. Thus, by retrieving
context, the human memory system can make the brain state resemble
the state it was in during encoding, facilitating further recalls.
We investigated this dynamic in a series of free-recall experiments in
which encoding task context varied within a list. Subjects exhibited
clustering of recalls by task context; this effect interacted with temporal
clustering. We present a model of memory search based on
Howard and Kahana’s Temporal Context Model that explains these re-