S1 (FriAM 1-65) - The Psychonomic Society

Friday Afternoon Papers 86–91
people often experience intrusive remindings, and make efforts to exclude
the unwanted memory from awareness. Prior work has established
that suppressing retrieval in this way recruits executive control
regions in the dorsolateral prefrontal cortex (DLPFC) that downregulate
activation in the hippocampus, impairing later retention.
Here, we investigate the neurobiological mechanisms underlying the
intrusion experience. In an adapted version of the “think/no think”
procedure, subjects reported after each suppression trial whether the
unwanted memory had intruded into awareness. The results show that
although subjects initially report many intrusions (~50%), these intrusions
decline with practice, with later memory impairment predicted
by this decline. Moreover, intrusions were associated with decreased
engagement of the DLPFC and elevated activity in the
hippocampus. These findings suggest that intrusive memories reflect
a failure to engage DLPFC during suppression, and that successful
down-regulation of hippocampal activation is an essential component
of memory control.
2:10–2:25 (86)
Independent Cues Are Not Independent. GINO CAMP, DIANE
PECHER, HENK G. SCHMIDT, & RENÉ ZEELENBERG, Erasmus
University Rotterdam—Retrieval practice with particular items from
memory (e.g., orange) can result in forgetting of related items (e.g.,
banana) that are associated to the same cue (e.g., FRUIT). This retrievalinduced
forgetting effect can be explained by both interference and inhibitory
processes. The independent cue technique has been developed
to differentiate between the contributions of interference and
inhibition to the forgetting effect. Independent cues are not associated
to the practiced item (e.g., monkey–b___ for banana). Inhibition theory
predicts forgetting with this type of cue. However, interference
theory predicts forgetting only with the studied category (FRUIT) and
does not predict forgetting with independent cues. Therefore, forgetting
with independent cues is seen as an empirical criterion for inhibition.
However, in three experiments, we demonstrate experimentally
that, even when participants are only cued with independent cues,
studied categories are activated at test. Thus, independent cues may
not differentiate effectively between interference and inhibition.
2:30–2:45 (87)
Long-Term Episodic Inhibition and Sleep. MIHALY RACSMANY,
Hungarian Academy of Sciences, MARTIN A. CONWAY, University
of Leeds, & GYULA DEMETER, Budapest University of Technology
and Economics (sponsored by Martin A. Conway)—Studies of retrieval
inhibition have persistently found that retrieval practice of selected
category items from a previously studied list reduces recall of
studied unpracticed items from the same category. Past research suggests
that this effect is short-term. Two experiments investigated the
long-term effect of retrieval practice and its relationship to sleep. In
both experiments two groups of subjects undertook a selective practice
paradigm with a 12-h delay between practice and recall. One
group (sleepers) had a full night’s sleep during delay, while the other
group (nonsleepers) recalled at the end of the day. Both groups
showed highly reliable retrieval-induced forgetting. In the second experiment
a surprise free recall procedure was used. A significant inhibitory
effect for the sleepers was again found but there was no reliable
effect for the nonsleepers. These findings are considered in terms
of consolidation of the contents of episodic memories.
Word Processing
Seaview, Friday Afternoon, 1:30–3:30
Chaired by Julie E. Boland, University of Michigan
1:30–1:45 (88)
Contextual Modulation of Dominant Homophone Meaning in the
Visual World. LILLIAN CHEN & JULIE E. BOLAND, University
of Michigan (read by Julie E. Boland)—In a visual world eye tracking
study, participants heard homophones in either neutral or subordinate-
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biased contexts (e.g., NEUTRAL, Amanda didn’t supervise her little
brother, who ended up dropping the glasses; BIASED, The dishwashers
washed the plates, the silverware, and finally the glasses). At homophone
onset, four pictures appeared: subordinate homophone meaning
(drinking glasses), dominate meaning shape competitor (handcuffs,
for eyeglasses), and two unrelated pictures. The shape
competitor was used to index subliminal activation of the dominant
meaning. Context influenced the proportion of fixations on both the
subordinate picture and the shape competitor, beginning with the second
fixation after the pictures appeared. Nonetheless, the shape competitor
attracted more fixations than expected by chance, even in the
subordinate-biased condition. This pattern is similar to the subordinatebias
effect reported in reading experiments (Binder & Rayner, 1998):
Context modulates the activation of homophone meanings, but the
dominate meaning remains partially activated in subordinate-biased
contexts.
1:50–2:05 (89)
Selection of Homograph Meaning: Implicit Memory Effects in
Episodic Memory. DAVID S. GORFEIN, Adelphi University, VIN-
CENT R. BROWN, Hofstra University, & EMILY EDWARDS, University
of Texas, Arlington—Traditional research in meaning selection
for ambiguous words (homographs/homophones) has focused on semantic
tasks such as the selection of a meaning for the ambiguous
word in a biasing context and for the same word presented later in a
similar or different semantic context. We have previously demonstrated
that an ambiguous word presented along with a picture consistent
with its secondary meaning induces a bias which is maintained
across relatively long time intervals, many intervening trials, changes
in task context, and changes in response requirements. These findings
are now extended to transfer from the initial secondary-meaning picture
priming task to an episodic memory task, free recall. The data
support the interpretation that the picture priming task alters the
meaning representation of the words, thereby affecting the frequency
and pattern of recall not only for the ambiguous words themselves, but
for words related to the ambiguous words’ initially dominant and secondary
meanings.
2:10–2:25 (90)
Bricks Don’t Breathe: Semantic Decisions Are Made by Weighing
Evidence For and Against Category Membership. DIANE PECHER
& RENÉ ZEELENBERG, Erasmus University Rotterdam, & ERIC-
JAN WAGENMAKERS, University of Amsterdam—In the animal decision
task words are categorized as animals or nonanimals. Deadline
models propose that decisions are based on activation of an animal
feature in combination with a temporal deadline (Carreiras, Perea, &
Grainger, 1997; Forster & Hector, 2002). Instead, we propose that the
decision process weighs several features that provide partial evidence
for either an animal or a nonanimal decision. If this weighing provides
strong evidence for either response, performance is better than if the
weighing provides only weak evidence for either response. In Experiment
1 performance was worse for words having features correlated
with the opposite response (e.g., organic for a nonanimal) than for
words not having such features. In Experiment 2 nonanimal responses
were faster than animal responses if the proportion of nonanimals was
high. These results are problematic for a deadline model but consistent
with a model combining evidence from different features.
2:30–2:45 (91)
An REM Model for Animal Decision. ERIC-JAN WAGENMAKERS,
University of Amsterdam, & DIANE PECHER & RENÉ ZEELEN-
BERG, Erasmus University Rotterdam—In animal decision, people
have to quickly decide whether or not words such as “mountain” or
“parrot” refer to an animal. This task requires that people access both
orthographic and semantic information. Previous research has shown
that (1) activation of semantic information occurs before orthographic
processing is complete; (2) performance for typical animals (e.g.,
dog) and nonanimals (e.g., computer) is better than performance for