S1 (FriAM 1-65) - The Psychonomic Society

Friday Afternoon Papers 127–130
falo—Four moving-window online reading experiments sought to
replicate structural priming for reduced relatives observed in late eye
tracking measures (Traxler & Pickering, 2004) and to determine
whether priming would be eliminated if distractors contained similar
contingent cues (i.e., repeated verbs and agentive by-phrases) as experimental
items. Kim and Mauner (2007) demonstrated that including
the same contingent cues in distractors eliminated priming for ambiguous
sentential complements. Although structural priming was
never observed, split-half analyses of the experiments revealed facilitated
processing of reduced relative targets in the second halves of
experiments relative to the first halves, with strongest effects emerging
when there was a combined contingent cue (i.e., verbs and agentive
by-phrases both repeated in prime and target). Moreover, as contingent
learning cues were progressively disrupted, the ambiguity
effect size increased. Previously reported facilitation in the processing
of reduced relatives may be due, at least in part, to contingent
cuing.
Motor Control
Shoreline, Friday Afternoon, 4:10–5:30
Chaired by Jerome Cohen, University of Windsor
4:10–4:25 (127)
Factors Affecting Rats’ Fear of Falling on the Horizontal Ladder.
JEROME COHEN, ANCA MATEI, & XUE HAN, University of Windsor—Many
factors affect our fear of falling as we climb above uneven
terrain. Chief among them are our perception of the depth of the
ground below us, our prior experience with prior falling episodes, and
our current age-related balance/motor control. To more systematically
investigate these factors, we have conducted a series of experiments
with rats on the horizontal ladder that transverses over “shallow” and
“deep” areas of flooring. We analyze how easily rats recover their running
speeds to baseline after experiencing collapsible rungs at various
locations on the ladder as a function of these three variables. We discuss
how our methodology and experimental designs can be incorporated
in neuroscience research concerning motor control and balance.
4:30–4:45 (128)
Stroke Therapy Using Wearable Robots and Ramachandran
Mirror Technique Produces Functional Improvement. MICHAEL K.
MCBEATH, FLAVIO DASILVA, & THOMAS G. SUGAR, Arizona
State University, NANCY E. WECHSLER, Midwestern University, &
JAMES KOENEMAN, Kinetic Muscles, Inc.—We tested functional
recovery of long-term hemiparetic stroke patients utilizing a
videogame-based repetitive motion task. Conditions were designed to
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manipulate both motor stimulation and a sense of bimanual agency.
Nine patients with varying severity of hemiparesis participated in four
1-month therapy conditions comprised of hour-long, biweekly therapy
sessions: (1) control, a nontreatment period; (2) robot only repetitive
motion, externally controlled, robot-assisted movements of effected
arm; (3) optical mirror, illusory percept of arm motion induced by
moving unaffected arm in front of sagittally oriented mirror; and
(4) robotically coupled motion, actively controlled, robot-assisted
movements of affected arm that mimic unaffected arm. The results
confirmed significant functional motor improvement during test therapies
compared to the control period, with all three test therapies
showing promise for some recovery. The findings support the clinical
value of an integrated therapy structure that induces broad neural engagement
including robot-assisted motor therapy and allowing individuals
to experience purposeful bimanual agency, even if illusory.
4:50–5:05 (129)
Visual Prism Adaptation and Hemispheric Asymmetry. GORDON
M. REDDING, Illinois State University, & BENJAMIN WALLACE,
Cleveland State University—Under conditions producing spatial realignment
in the visual eye–head sensory–motor system, visual
straight ahead was asymmetrically shifted more leftward for leftward
displacement when tested from the left than from the right hemispace.
In contrast, visual straight ahead was shifted by the same amount for
testing from both hemispaces with rightward displacement. These results
are consistent with the hypothesis that left and right visual hemispaces
are asymmetrically represented in the two hemispheres: Both
hemispaces are represented in the right hemisphere, but only the right
hemispace is represented in the left hemisphere.
5:10–5:25 (130)
Rapid Effects of Omega-3 Fats on Brain Function. SETH ROBERTS,
University of California, Berkeley—I measured the effect of omega-3
fats on my brain by comparing flaxseed oil (high in omega-3) with
other plant fats (low in omega-3) and with nothing. Flaxseed oil improved
my balance, increased my speed in a memory-scanning task
and in simple arithmetic problems, and increased my digit span. The
first three effects were very clear (t � 6). The effects of flaxseed oil
wore off in a few days and appeared at full strength within a day of
resumption. The best dose was at least 3 tablespoons/day, much more
than most flaxseed oil recommendations. Supporting results come
from three other subjects. Because the brain is more than half fat, it
is plausible that type of dietary fat affects how well it works. The most
interesting feature of these results is the speed and clarity of the improvement.
The tools of experimental psychology may be used to determine
the optimal mix of fats for the brain with unusual clarity.