Abstracts 2005 - The Psychonomic Society

Papers 112–118 Friday Afternoon
neither young nor old demonstrated costs to the ongoing task either
in accuracy (Experiment 1) or in speed of responding to the ongoing
task (Experiment 2). In contrast, for nonfocal cues, older adults maintained
levels of prospective memory performance comparable to that
of young adults, but at a cost to ongoing task performance (reduced
accuracy and longer response times). These data provide strong support
for the idea that when the prospective memory cue is focal to the
ongoing task, prospective memory retrieval is typically spontaneous
and, accordingly, is not likely to produce age-related decline. Second,
older adults’ resource allocation policies with nonfocal target events
clearly can support prospective memory at levels comparable to those
of younger adults, albeit at a price to ongoing activity.
4:50–5:05 (112)
Effects of Aging and Working Memory Load on Prospective Memory.
ROBERT WEST & RITVIJ BOWRY, University of Notre Dame—
ERPs were used to examine the effects of aging on the neural correlates
of prospective memory. In the task, we varied working memory
load and prospective memory load in a 2 � 2 factorial design. Individuals
judged whether letters had repeated one or two items back in
the list. For half of the blocks, they also made prospective responses
when letters were presented in a specific color. The ERP data revealed
several interesting findings: (1) n-back load influenced the amplitude
of the N300 in younger adults, but not in older adults, (2) prospective
memory was associated with the recruitment of different neural generators
in younger and older adults, and (3) the prospective interference
effect was associated with the recruitment of different neural
generators in younger and older adults. These finding support the idea
that there are age-related differences in the recruitment of preparatory
attention that facilitates the realization of intentions.
5:10–5:25 (113)
“Haste Makes Waste”: A Momentum Theory of Prospective Memory
Test Performance. PETER GRAF, University of British Columbia—
Prospective memory (ProM) is the ability to make plans and to recollect
them later upon the occurrence of the appropriate retrieval cues.
In the context of everyday life, we may fail to follow through with a
plan, such as posting a letter, because we are immersed in a heated
conversation at the time of walking past the mailbox. The present research
explored the hypothesis that ProM test performance is determined
by the momentum of the activity—the ongoing conversation—
in which the retrieval cues are encountered, with high momentum
activities defined as those that are more difficult to interrupt. We manipulated
task momentum in a number of different ways—for example,
by giving subjects speed versus accuracy instructions for an
old/new recognition test. The results showed higher ProM test performance
for cues presented in lower momentum ongoing tasks.
Cuing Visual Attention
Grand Ballroom West, Friday Afternoon, 3:30–5:30
Chaired by Soledad Ballesteros
Universidad Nacional de Educación a Distancia, Madrid
3:30–3:45 (114)
Effects of Word Fragmentation, Cortical Magnification, and Visual
Eccentricity on Stroop Effect. SOLEDAD BALLESTEROS & JOSÉ M.
REALES, Universidad Nacional de Educación a Distancia, Madrid,
& DIONISIO MANGA, Universidad de León—Directing attention to
a spatial location improves responses to stimuli presented at that location.
However, selective attention is not totally successful. In a series
of experiments using the Stroop paradigm, we examined the effect
of stimulus fragmentation on item type (congruent, incongruent,
neutral, emotional, negative, semantic, orthographic), experimental
design (blocked, random), and stimulus eccentricity on interference
and facilitation. In this study, congruent, incongruent, neutral, and semantically
related words at four levels of fragmentation were presented
appropriately enlarged by a magnification factor at two eccen-
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tricities to the left or to the right of fixation. Results showed that as
in previous studies, both item type and fragmentation level were significant.
However, neither stimulus size nor its interaction with other
factors was significant. Results suggest that when the stimuli are enlarged
by a magnification factor to match eccentricity, Stroop effects
at a foveal location are similar to those presented at the periphery.
3:50–4:05 (115)
Visual Attention and the Semantics of Space: Beyond Central and
Peripheral Cues. BRADLEY S. GIBSON, University of Notre Dame,
& ALAN F. KINGSTONE, University of British Columbia—The distinction
between central and peripheral cues has played an important
role in understanding the functional nature of visual attention for the
past 30 years. In the present talk, we propose a new taxonomy that is
based on linguistic categories of spatial relations. Within this framework,
spatial cues are categorized as either “projective” or “deictic.”
Using an empirical diagnostic developed by Logan (1995), we demonstrate
that word cues such as above, below, left, and right express projective
spatial relations, whereas arrow cues, eye gaze cues, and
abrupt onset cues express deictic spatial relations. Thus, the projective
versus deictic distinction is shown to crosscut the more traditional
central versus peripheral distinction. The theoretical utility of this new
distinction is discussed in the context of recent evidence suggesting
that a variety of central cues can elicit reflexive orienting.
4:10–4:25 (116)
The Attentional White Bear Phenomenon: The Mandatory Allocation
of Attention to Expected Distractor Locations. YEHOSHUA
TSAL & TAL MAKOVSKI, Tel Aviv University—We report additional
data supporting the “attentional white bear” hypothesis. We devised a
prestimulus probe method to assess the allocation of attention as a
function of subjects’ top-down expectancies concerning distractor and
target locations. Participants performed the flanker task, and distractor
locations remained fixed. On some trials, instead of the flanker
display, two simultaneous dots appeared. The dot in the expected target
location was perceived to occur before the dot in the expected distractor
location. More interesting, the dot in the expected distractor
location was perceived to occur before the dot in the expected empty
location, indicating that attention is allocated to expected distractor
locations prior to stimulus onset. We propose that a process-all mechanism
guides attention to expected locations of all stimuli, regardless
of task demands, and that this constitutes a major cause for failures
of selective attention.
4:30–4:45 (117)
Endogenous Cuing and Saccade Curvature. JAN THEEUWES &
STEFAN VAN DER STIGCHEL, Vrije Universiteit Amsterdam—In a
standard Posner paradigm, participants were endogenously cued to attend
to a peripheral location in visual space without making eye movements.
Participants responded more quickly to target letters presented
at cued locations than to those at uncued locations. On some trials, instead
of a manual response, participants had to move their eyes to a
location in space. The extent to which the eyes curved away from cued
and uncued locations was related to the dynamics of attention allocation.
Not only did the eyes curve away from validly cued locations,
but also when the cue was invalid and attention had to be shifted to
the uncued location, the eyes curved away, but now from the uncued
location. We show that covert endogenous shifts of attention always
result in activity in the oculomotor system, even in tasks in which participants
covertly direct attention to a location in space
4:50–5:05 (118)
Alternative Accounts of the Effect of Prior Probability on Response
Time. JOHN PALMER & MARIA K. MCKINLEY, University of Washington,
& MICHAEL N. SHADLEN, HHMI and University of Washington—Perceptual
decisions are based on a combination of sensory
evidence and prior knowledge. We address how sensory evidence is
combined with prior knowledge of the probability of stimulus alter-