S1 (FriAM 1-65) - The Psychonomic Society

Posters 1028–1034 Thursday Evening
tion cost commonly attributed to task-set inhibition. An experiment is
reported in which subjects were induced to chunk sequences such that
n�2 repetitions occurred within or between chunks. Direct evidence of
chunking was obtained and n�2 repetition cost was smaller when n�2
repetitions occurred within chunks than between chunks. These findings
are consistent with the idea that the reduced n�2 repetition cost reflects
priming of task goals rather than direct modulation of task-set inhibition.
(1028)
The Effect of Working Memory Load on Task Choice in Voluntary
Task Switching. STARLA M. WEAVER & CATHERINE M. ARRING-
TON, Lehigh University (sponsored by Catherine M. Arrington)—The
voluntary task switching (VTS) paradigm allows subjects to choose
the specific task to be performed on each trial. Subjects are instructed
to perform each task equally often and in a random order; however,
they tend to show a repetition bias, performing fewer switches than
would be expected in a random sequence. Lack of executive resources
was assessed as a contributor to this repetition bias. A memory load
manipulation was used to limit the executive resources available during
VTS. Simple memory storage tasks, which required only the
maintenance of memory letters, had no impact on VTS performance.
However, a working memory load, which required the active manipulation
of memory letters during VTS, differentially reduced the proportion
of switches such that greater repetition bias was found under
greater working memory loads. The availability of executive resources
at the time of task performance appears to influence task choice.
(1029)
Directed Inhibition of Previewed Distractors in a Stroop Task:
Underlying Mechanism. HSUAN-FU CHAO, Chung Yuan Christian
University—In a previous study, it has been demonstrated that Stroop
interference could be reduced by precuing the distracting word and
asking participants to inhibit the previewed distractors in advance.
This study aimed at investigating the underlying mechanism in this
distractor previewing effect. Experiment 1 replicated the effect of distractor
viewing when both incompatible and compatible trials were
used. Experiments 2–4 demonstrated significant effects of distractor
previewing when cues and distractors differed in forms. In Experiment
5, a cost was obtained for conflict trials in that the previewed
item cued the target color rather than the distractor word. Finally, the
cue validity was removed in Experiment 6, and no effect of distractor
previewing was observed. These results ruled out the explanations in
terms of response set, temporal segregation, and distractor facilitation.
The intentional inhibition account can best explain these findings.
(1030)
What Happens to Attention When We Drink? GREGORY J. H.
COLFLESH & JENNIFER WILEY, University of Illinois, Chicago—
It is believed that alcohol use has a negative impact on attentional
processes, but the affected cognitive mechanisms are not well understood.
Clinical literature has advanced two theories describing how alcohol
affects attention. According to the alcohol myopia theory, alcohol
consumption decreases the focus of attention (Steele & Josephs,
1990). Salience theories suggest that increased exposure to alcohol, or
alcohol consumption, increases the salience of alcohol-related stimuli
(Jones, Jones, Smith, & Copley, 2003), which acts as a source of distraction
from other stimuli. The current study attempts to identify the
attentional processes that alcohol use affects by examining performance
on a battery of selective and divided attention tasks, including
inattentional blindness, a modified Stroop task, and change blindness,
while participants are intoxicated (BAC .075). Both neutral and alcoholrelated
stimuli are used to test the myopia and salience accounts. Additionally,
interactions between individual differences in WMC and
changes in performance under intoxication will be discussed.
(1031)
Separating Exogenous From Endogenous Factors in Attentional
Capture. MATTHEW YANKO, Simon Fraser University, PAOLA
55
POIESE, University of Trento, & THOMAS M. SPALEK & VINCENT
DI LOLLO, Simon Fraser University—Attentional capture occurs
when a task-irrelevant stimulus involuntarily receives attentional priority.
Two sources of capture have been proposed in the literature: exogenous
(stimulus-bound) and endogenous (goal-oriented). Although
the two sources have often been regarded as mutually exclusive, we
show that both can act concurrently and can be decoupled within a single
experiment. The displays consisted of RSVP streams of differently
colored letters with a target letter defined by a specific color. In some
conditions, irrelevant color singletons surrounded either one RSVP
item (Experiment 1) or all items (Experiment 2). Experiment 1 provided
evidence for both exogenous and endogenous sources of capture.
Experiment 2 reduced or eliminated exogenous sources by eliminating
the uniqueness of the sudden onset of the peripheral
distractors. The novel contribution of this work is that it provides unambiguous
evidence that attention can be captured exogenously as
well as endogenously. The results are consistent with dual-pathway accounts
of attentional control.
(1032)
Decomposing the Multisource Interference Task. HEATHER M.
GILMORE & ELISE TEMPLE, Cornell University (sponsored by
Grover C. Gilmore)—The multisource interference task (MSIT) combines
different types of interference known to delay reaction time for
the purpose of maximizing cognitive interference. Previous work has
not addressed the separate influences of each source of interference.
The present study was designed to decompose the sources of interference
to determine their independent contributions. Participants
were instructed to identify the number that was different in a threedigit
array. Experiment 1 examined flanker interference, the combination
of flanker and spatial interference, and the effect of a font cue.
Additionally, blocked versus mixed design was compared. It was
found that two types of interference were more difficult than one type
of interference and that blocking of interference type yielded more potent
effects. Experiment 2 replicated the results and additionally examined
spatial interference. The results of the study can be used to design
a maximally potent MSIT.
(1033)
Goal Activation or Inhibition? Disentangling Forms of Top-Down
Control. MARY K. ASKREN & CINDY LUSTIG, University of
Michigan—The role of goal activation in conflict resolution is well
accepted, but inhibition’s role is more controversial. We used a taskswitching
procedure to disentangle the effects of demands on goal activation
versus inhibition. Goal activation demands were measured by
rule-incompatibility costs: Poorer performance on trials for which the
two task rules led to opposite responses as compared with trials where
both rules led to the same response. These rule-incompatible trials required
subjects to activate the correct goal in order to produce the correct
response. The results (n = 48 young adults) indicate that rule incompatibility
only led to slowing when it was confounded with
bottom-up, Stroop-like conflict. This pattern suggests that even when
participants have the correct goal activated, additional inhibitory
processes are needed to suppress bottom-up, stimulus-driven conflict.
A follow-up study examines which of these processes—goal activation
or inhibition—shows larger differences between young and old
adults.
• AUTOMATIC PROCESSING •
(1034)
Affect Priming Versus Sequential Affect Judgment. DEAN G. PUR-
CELL, Oakland University, & ALAN L. STEWART, Stevens Institute
of Technology—Sequences of two faces displaying facial affect were
presented under conditions of affect priming and under conditions of
sequential affect judgment (SAJ). The priming task required the observer
to judge the affect of only the second of the two faces. Affect
priming was found as well as an anger inferiority effect (AIE). The