PSYCHOLOGY
Terry Blumenthal
-
with Christopher Turner, NBAT
Neonatal brain injury and schizophrenia: from receptors
to behavior
Awarded $20,000; $10,000 Reynolda campus, $10,000
Health Sciences
Source: WFU Cross-Campus Collaborative
Research Support Fund
Schizophrenia affects about 3 million in the US alone
and costs around $35 billion annually. Blocking the NMDA
receptor with the experimental drug MK801 can promote
schizophrenic behavior not only in adults but also in
neonatal rats that are allowed to mature to adulthood.
This developmental model has shown that MK801 induces
neuronal death in brain regions known to display pathologies
in schizophrenia (dorsal thalamus, prefrontal, cingulated,
and retrosplenial cortex) though whether such injury
is linked to behavioral changes is not clear. This project
will examine whether MK801 promotes lasting neuronal
loss or if the brain can compensate and maintain neuronal
numbers despite robust apoptosis following postnatal
injury. A critical observation will be whether animals
that show pathologies at the histological level also
show them at the behavioral level. Deficits in sensorimotor
gating are a common symptom in schizophrenia, and a technique
known as PPI (prepulse inhibition) is one simple way
to test it. Normal subjects startled by a loud noise
adapt to it, if it is preceded by a soft noise, but schizophrenics
cannot. This response is species-preserved, found in
nonhuman primates as well as rodents, and disrupted by
NMDA receptor antagonists, like MK801. CCCRS funds will
be used to purchase the PPI apparatus and associated
software to test rat pups, injected with vehicle or MK801
and allowed to mature until P56, for disruption of PPI.
Their brains will be examined for histo-pathological
changes on a region-by-region basis. Once the behavioral
component of the model has been established, it will
present many opportunities for long-term collaborations
and student training.
This project seeks to develop a direct, stable, reliable,
quantitative measure of sensory gating in humans
and to determine whether it can detect sensory gating deficits
in clinical
populations. Dr. Blumenthal serves as a consultant
for the studies, which are conducted in the laboratory of
Dr. Neal
Swerdlow at the University of California, San
Diego.
Failures in the normal suppression, or gating,
of sensory information are associated with cognitive disturbances
in schizophrenia and sensory tics and premonitory
urges
that
often precede motor and vocal tics in Tourette’s Syndrome
patients. One laboratory approach to studying deficient gating
uses prestimulus effects on motor events (prepulse inhibition
of startle, or PPI). Another measure, prepulse inhibition
of perceived stimulus intensity, or PPIPSI, is assessed by
a direct report of the perceived intensity of a probe stimulus
in the presence and absence of a prestimulus. Under appropriate
conditions, subjects report that they perceive an intense,
abrupt stimulus – for example, a 118 dB noise burst,
a 40 psi air puff, or a 170 V cutaneous shock – as
less intense, if it is preceded by a weak prepulse.
This project aims to establish PPIPSI’s utility in
systematic studies of sensory gating in normal and disordered
populations. Studies will determine: 1) conditions for eliciting
maximal gating effects; 2) test/retest stability; 3) reliability
across experimental settings; 4) generalizability across
sensory modalities; 5) sensitivity in children; 6) the impact
of attentional manipulations; and 7) utility in detecting
deficits in patients with schizophrenia or Tourette’s
Syndrome.
- Testing Sensory Gating in Antisocial
Personality Disorder
Awarded $1,600 for the period 12/1/05 to
7/31/06
Source: WFU Social, Behavioral, and Economic Science Research Fund
Antisocial personality disorder (APD) may be partially based on an inability
to process certain types of information accurately and automatically. Prepulse
inhibition of startle (PPI), a measure of early information processing,
has been found deficient in several clinical disorders, such as schizophrenia
and obsessive-compulsive disorder. To learn more about the underlying physiology,
this study will measure startle and its inhibition by a prepulse in college
students who rate high or low on an APD questionnaire.
Dale Dagenbach, see Janine Jennings
William Fleeson
Integrating Processes and Structure in Personality
Awarded $184,063 for the period 7/1/07 to 6/30/08
Source: National Institutes of Health (NIH)
An important debate at the intersection of personality, developmental,
and social psychology is whether research should focus on individual
differences in reactions to situations or, because of stability
in the way the same person acts over time, on traits. This
project tests the hypothesis that both are needed and, in fact,
clarify each other. Specific aims will: (1) use independent
behavioral data to test the integration of process and structure;
(2) determine the amount of variability across the life span;
and (3) chart the contingencies and consequences of within-person
variability, individual differences in variability, and age
differences in variability.
This project aims to advance mental health theory by elucidating
the basic processes underlying behavioral flexibility. The
process model, which explains behavioral manifestations of
traits in reaction to situations, may help to clarify the mechanisms
of these links and to identify opportunities for intervention.
It will explore when flexibility becomes adaptive or maladaptive
by correlating individual differences with various indicators
of mental health. Its approach will also validate two important
methodological tools for psychology, mental health, and health
research: experience-sampling and self-report.
Michael Furr
- Impulsivity and Information Processing in Adolescent Cannabis
Abuse
Awarded $17,699 for the period 9/1/06 to 8/31/07
Source: National Institutes of Health
Adolescence is a period of considerable cognitive, emotional,
and social development. Young people experience maturational
changes related to reward-seeking, motivation, and self-regulation
across multiple domains of behavioral, executive, and physiological
functioning. Cannabis has a potentially negative effect on
any or all of these developmental processes. Although the effects
of its use, such as distorted perception, memory, and problem
solving, have been shown in animals and adults, the antecedents
and consequences of cannabis use on the developing cognitive,
neurophysiological, and behavioral processes during adolescence
are poorly understood.
This project uses a battery of new technologies to characterize
the effects of cannabis use on cognitive processes developing
during adolescence—specifically, attention, executive
functioning, and impulsive behaviors—and to compare
adolescent cannabis abusers to controls.
- Impulsivity Models: Behavioral Mechanisms
Awarded $15,081 for the period 4/1/06 to 3/31/07
Source: NIH
This project will advance our understanding of impulsivity
and its role in the development of severe conduct problems.
Two types of objective behavioral measures?rapid-decision
vs. reward-directed?will be compared among three groups
of adolescents with conduct disorder (CD): those without
histories of physical fighting; those with histories
of planning fights; and those who fight impulsively. Experiment
1 uses several task types concurrently to determine
which measures are most sensitive to group differences.
In
Experiment
2, performance feedback (reward, penalty, and combined
reward/penalty) is used to determine which task parameters
improve group discrimination and how each group’s
performance may be differentially modulated by feedback.
In both experiments, behavioral impulsivity performance
will be related to parent, teacher, and self-report
ratings for further validation. These studies will
help to determine
the basic mechanisms of impulsivity and to develop
the objective, replicable measures needed to answer
both
basic and applied research questions. The long-term
goal is to
determine how impulsivity relates to biological mechanisms,
treatment prediction, and outcome. Research focused
on understanding the unique causal pathways that lead
children
to develop patterns of severely antisocial and aggressive
behavior will advance treatment.
- Behavioral Models of Impulsivity: Alcohol
and 5-HT Effects
Awarded $17,699 for the period 4/1/07 to 3/31/08
Source: NIH
These studies aim to determine: (1) the dose-dependent
effects of alcohol and L-tryptophan manipulation on rapid-decision
and reward-directed models of impulsivity; (2) how a biological
state change produced by L-tryptophan manipulation can
moderate vulnerability to the behavioral effects of alcohol;
(3) how different components of impulsivity are differentially
affected by alcohol and L-tryptophan manipulations; and
(4) how baseline responses to these behavioral models relate
to one another and to self-reported measures of impulsivity.
Together, they may provide evidence that serotonin moderates
alcohol-induced behavioral impulsivity and inform further
exploration of what factors contribute to the individual
differences observed in impulsive behavior after alcohol
consumption. Healthy men and women will be evaluated at
intervals before and after the interventions, and each
will experience all the interventions in a repeated-measures
design. Experiment 1 examines dose effects of alcohol on
behavioral impulsivity. Experiment 2 examines dose effects
of L-tryptophan loading and depletion, which alter central
nervous system serotonin levels. Experiment 3 examines
the interactive effects of alcohol and L-tryptophan.
Janine Margaret Jennings
- with Dale Dagenbach
SHARP-P
Awarded $76,909 for the period 9/30/07 to 5/31/08
Source: National Institutes of Health/ WFU Health Sciences
The goal of SHARP is to design and to test the effects of an intervention to prevent various types of cognitive decline observed with aging through physical activity and mental training. SHARP-P, a pilot program, will evaluate several questions related to feasibility and examine the independent and combined effects of physical exercise and cognitive training on executive function. This project represents collaboration between the medical school and Reynolda campus investigators in the departments of Health and Exercise Science and Psychology.
Memory Training to Enhance Performance in Older Adults with
Mild Cognitive Impairment
Awarded $24,940 for the period 4/1/03 to 3/31/04
Source: WFU School of Medicine
The project aims to assess the efficacy of a behavioral intervention
for memory function in older individuals with Mild Cognitive
Impairment (MCI). In collaboration with colleagues, Dr. Jennings
has devised a recollection training procedure that resulted
in dramatic improvements in memory on the training task and
other measures of memory and cognitive function in healthy older
adults. To test the technique's value for MCI, 50 participants
diagnosed with the condition will undergo an assessment battery
of cognitive and memory function tasks and then be randomly
assigned to either recollection training or no-treatment control
conditions to determine the training's benefits. The project
will provide a graduate student stipend for one year.
James Schirillo
Acquisition of Instruments to Measure Visual Bias of
Occluded Auditory Signals in Three-Dimensional Space
Awarded $57,147 for the period 8/1/05 to 7/31/07
Source: NSF
With support from a Major Research Instrumentation award,
the Psychology department will acquire stereovision and audio
equipment that will be placed in an audiometric sound chamber
and configured to produce a 3-dimensional audio-visual environment
to measure the multisensory localization of visually occluded
auditory signals. Its custom design will make it the only one
of its kind in the United States.
Multisensory integration is typically studied with2-dimensional
stimuli. Designing experiments in a 3-D environment allows
occluding objects to be added, creating the ecologically
valid condition most encountered in nature. Recent advances
in environmental
acoustics and stereoscopic viewing technology offer an exciting
opportunity to explore how an object’s opacity or transparency
influences the extent to which flashes of light bias the perception
of where a sound burst originates. The project hypothesizes
that an object’s opacity constrains the extent to which
a light can bias the sound’s perceived location.
Results may change (1) how psychophysicists model auditory
occlusion in 3-D space; (2) what neuroscientists consider the
type of contextual factors that can influence the receptive
field properties of multisensory neurons; and (3) how engineers
design such environments as cockpits. The equipment will be
used by psychophysicists and neurobiologists at the professional,
graduate, and undergraduate level across the Reynolda and Health
Sciences campuses.
Eric Stone
- Strategies for communicating low-probability disease risk to health consumers
Awarded $9,055 for the period 9/30/07-8/30/08
Source: National Institutes of Health/Duke University
Increasing perceptions of colorectal cancer (CRC) risk should motivate screening, yet findings are inconsistent, possibly due to poor communication of disease precursors, probability of occurrence, consequences, and methods to prevent or diminish the threat. The overall goals of this study are to develop an intervention that addresses each dimension of risk and to assess how it affects screening intentions. The likelihood of getting CRC is the most difficult component to convey. It is typically expressed numerically, but the sense that probabilities are small may deter screening. This preliminary project will determine whether the standard numerical display of likelihood information decreases motivation to screen and, if so, to develop and test an alternate means using a graphic display to increase motivation to screen.
- Using Cognitive Feedback to Improve the Accuracy of Judgments
Awarded $4,000 for the period 1/03 to1/04
Source: WFU Social, Behavioral, and Economic Science Research Fund
The proposed research seeks to improve the accuracy of people's
judgments by providing cognitive information feedback; i.e.,
feedback regarding the judgment strategy the person is using.
Although previous work has not supported the efficacy of cognitive
information feedback, we believe that in those experimental
situations, participants were already aware of their judgment
strategies. We plan to present participants with a more complex
task where they will be less aware of their judgment strategies
in order to determine whether or not cognitive information
feedback can be helpful in training people - e.g., doctors
and clinicians - to make more accurate judgments.
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