S1 (FriAM 1-65) - The Psychonomic Society

Thursday Evening Posters 1035–1041
affect of the second face more strongly determined this AIE than did
the affect of the first face. The SAJ task required observers to compare
first and second stimulus affect in order to determine whether
they were congruent. As in the priming task, an AIE was found. However,
unlike in the priming task, priming was not evident and the observed
AIE was determined by the affect of the first face. This was so
despite the active processing of both faces required in the SAJ task.
(1035)
Modulation of the Stroop Effect by Inhibition of Return. JONG
MOON CHOI & YANG SEOK CHO, Korea University—In a visual
orienting task, reaction times are longer when a target is presented at
a cued location than at an uncued location about 1,000 msec after an
exogenous cue flashed. This phenomenon is called inhibition of return
(IOR). To examine whether the magnitude of the interference effect
would be modulated by IOR in the Stroop task, a color carrier, a
color word, or neither of them was presented at the cued location 800,
1,050, or 1,300 msec after an exogenous cue flashed. The Stroop effect
was largest when nothing was presented at the cued location, intermediate
when the color carrier was, and smallest when a color word
was at 1,050-msec SOA. However, this interaction disappeared at
800-msec and 1,300-msec SOAs. This reduced Stroop effect is due to
the stimulus not being processed efficiently because of IOR, which is
supposed to provoke lack of attention.
(1036)
Biologically Significant Stimuli Produce Visual Prior Entry.
GREG L. WEST, ADAM A. K. ANDERSON, & JAY PRATT, University
of Toronto (sponsored by Jay Pratt)—It remains unclear whether
biologically significant stimuli, such as neutral or threatening faces,
receive attention prior in time to other contemporaneous stimuli. Visual
prior entry, as measured by temporal order judgments (TOJs),
rests on the premise that allocated attention accelerates perception;
that is, attended stimuli are perceived before unattended stimuli, and
thus this method is a sensitive and direct measure of attentional capture.
We demonstrate, using a novel TOJ paradigm without cues, that
schematic faces of both neutral and angry emotional valence show visual
prior entry effects; that is, these stimuli are perceived prior in
time in comparison with competing stimuli. We further extend these
results by contrasting effects produced both by schematic and real
face stimuli. This study provides direct evidence that biologically significant
stimuli, in schematic or photographic form, bias the contents
of awareness and thus are perceived prior in time.
(1037)
Learning to Flexibly Dual-Task: When Single-Task Automaticity
Is and Is Not Enough. NICOLE M. HILL & WALTER S. SCHNEIDER,
University of Pittsburgh (sponsored by James Voss)—Dual processing
theory predicts that controlled but not automatically processed
single-task performance will decline in a dual-task context. However,
declines in a dual-task context occur regardless of processing mode.
We posit that (1) single-task learning is necessary but not sufficient
for automatic dual-task performance, (2) extensive dual-task practice
develops dual-task automatic processing, and (3) automatic dual-tasks
can be flexibly performed—that is, novel dual-task combinations
(NDTC) and single-trained-only targets (STOT). Ninety stimuli/sec
were presented in a display containing four distinct tasks. Single-todual
transfer resulted in declining performance; training nearly attenuated
this decline. The NDTC and STOT conditions produced a modest
dual-task cost relative to untrained dual-tasking. This suggests that
single-task (consistent) training retains a degree of controlled processing
that was released by dual-task training; furthermore, performance
became flexible and remained high-level despite task alterations.
(1038)
A Word Choice: The Effect of Emotion on Lexical Decision and
Accuracy. JOSEPH M. BAKER & STEPHEN R. SCHMIDT, Middle
Tennessee State University (sponsored by Stephen R. Schmidt)—Past
56
research has failed to show significant lexical decision reaction time
differences between emotional and nonemotional words. It is possible
that the relatively long stimulus presentations employed in earlier
studies were responsible for these null effects. In order to investigate
the role of stimulus durations in the lexical decision task, emotional,
neutral, and nonwords were presented to participants randomly in one
of four stimulus durations (e.g., 30, 50, 75, and 100 msec). Emotional
words were responded to faster than neutral and nonwords. Also, participants
were more accurate in identifying emotional words than neutral
words within all presentation durations, with the largest difference
occurring within the 30-msec presentation duration. These results
suggest that lexical decision reaction time differences do exist between
emotional and neutral words, as well as supporting findings that
suggest that emotional words are attended to faster than neutral words.
(1039)
Deviations of Pointing Movements Toward the Irrelevant Stimulus
Location in Vertical and Horizontal Simon Tasks. SIMONA BUETTI
& DIRK KERZEL, University of Geneva—In the Simon effect (SE),
responses to the color of a stimulus are faster when the irrelevant position
of the colored stimulus is congruent with the response location.
The SE decreases with increasing reaction times (RTs) for horizontal,
but not for vertical, stimulus arrangements. Consistent with RTs, the
lateralized readiness potential (LRP) shows an early deflection in incongruent
trials of horizontal, but not vertical, Simon tasks. We observed
that the trajectories of pointing movements were attracted by
the irrelevant stimulus position. Furthermore, deviations toward the
irrelevant stimulus decreased with increasing RT for both horizontal
and vertical Simon tasks. Thus, the SE in movement parameters mirrored
the time course in RTs for horizontal, but not vertical, stimulus
arrangements. These results suggest that the early deflection in LRPs
may underlie the time course of the SE in RTs, but not the SE in movement
trajectories.
(1040)
A Task-Difficulty Artifact in Subliminal Priming. MICHAEL S.
PRATTE & JEFFREY N. ROUDER, University of Missouri, Columbia
(sponsored by Jeffrey N. Rouder)—Subliminal priming is said to
occur when a subliminal prime influences the identification of a subsequent
target. Most subliminal priming claims are based on separate
target and prime identification tasks. We argue that because prime
identification is difficult, participants’ motivation wanes and, consequently,
prime-identification performance suffers. Identification of
weak stimuli may, therefore, appear at chance. To test this artifact, we
increased the ease of the prime-identification task by intermixing easy
(visible) primes with difficult (near liminal) ones. In Experiment 1,
this strategy of intermixing easy primes is shown to raise identification
of the difficult ones. In Experiment 2, prime duration was lowered
such that prime identification was near chance in intermixed presentations.
Under these conditions, we fail to observe any priming
effects. Hence, previous demonstrations of subliminal priming may
simply reflect a task difficulty artifact.
(1041)
Coding Strategies in Number Space. OLIVER LINDEMANN, Radboud
University, JUAN M. ABOLAFIA, Miguel Hernandez University,
JAY PRATT, University of Toronto, & HAROLD BEKKERING,
Radboud University Nijmegen (sponsored by Harold Bekkering)—
The present study investigates the impact of task demands on the association
of spatial and numerical response codes (SNARC effect).
Participants were instructed to memorize three simultaneously presented
Arabic digits describing a left-to-right ascending number sequence,
a descending sequence, or a disordered sequence. Afterward,
participants indicated the parity status of a centrally presented digit.
As the response latencies showed, SNARC effects in the parity task
were mediated by the coding requirements of memory tasks. That is,
SNARC effects were present only after memorizing ascending or disordered
number sequences but disappeared after processing descend-