Fall 2008 Colloquium Series
Speaker: Dr. Cynthia A. Crawford, Dept. of Psychology, CSU San Bernardino
Topic: Effects of Early Methylphenidate Exposure on Morphine and Cocaine Medicated Behaviors in the Adult Rat
Methylphenidate usage in preschool aged children (2 to 5 year olds) has become increasingly common over the last decade. The increased use of methylphenidate is troubling, as there are very few studies examining the long-term effects of stimulants in this age group. Moreover, developmental studies in rodents suggest that early exposure to methylphenidate may alter later responsiveness to drugs of abuse and cause persistent changes in neuronal functioning. These studies have so far produced conflicting results, with some studies indicating that methylphenidate exposure decreases later drug responsiveness after methylphenidate exposure. An interesting feature of these studies is that exposure to methylphenidate during the earlier preadolsecent period reduces the responsiveness to later psychostimulant administration. Data gathered in our laboratory indicates that methylphenidate exposure during the preweanling period (postnatal day (PD) 11-PD 20) enhances later responsiveness to rewarding stimuli and alters opioid receptor system functioning. These findings suggest that methylphenidate exposure during very early development may increase later drug vulnerability.
Speaker: Timothy A. Allen, Ph.D. Thesis, Department of Psychology, Yale University
Topic: Cortically-Mediated Acquired Fear
Perirhinal cortex (PR) is one of the earliest and most severely affected regions in Alzheimer’s disease. PR is an understudied region of the mammalian brain at the nexus of facts, feelings and percepts. The role of PR was examined in Pavlovian fear conditioning to 22 kHz ultrasonic vocalizations (USVs) produced by rats. Twenty-two kHz USVs are ethologically-relevant calls that are produced during distressing events and serve as conspecific alarm calls. Unlike pure tone stimuli, fear conditioning to 22 kHz USVs is impaired by lesions to the PR. Multiple techniques were used to test the hypothesis that the essential stimulus feature of 22 kHz ultrasonic vocalizations is the discontinuous structure of a bout of calls. PR single-unit activity was found to respond similarly to 22 kHz USVs and 22 kHz discontinuous call matched to the on/off structure of a bout of calls, but differently to continuous tones. In differential fear conditioning rats were able to discriminate between continuous tones and 22 kHz USVs, but not between discontinuous tones and 22 kHz USVs. Pretraining lesions of PR similarly impaired fear conditioning to 22 kHz USVs and discontinuous tones, but not continuous tones. Depending upon whether a tone or 22 kHz USV was used as a stimulus, different types of single-unit plasticity and latencies were observed in PR. Inactivating the amygdala with fluorescent muscimol impaired fear conditioning to 22 kHz USVs. Overall, the data support the hypothesis that an essential perirhinal-amygdala circuit underlies fear conditioning to 22 kHz USVs. Theoretically, PR supports a unitization process that forms a discontinuous bout of calls into a singular auditory object, which can subsequently be associated with fear.
Speaker: Bettina Casad, Ph.D., Department of Psychology and Sociology, California State Polytechnic University, Pomona
Topic: Effects of Stereotype Violation
How are people who violate stereotypes evaluated? Are there contextual features and individual difference variables that affect evaluations? How does being a stereotype violator affect a person’s performance? Utilizing a variety of measurement types, including subjective, objective, and implicit, the research presented in this colloquium will examine the answers to these questions, looking at multiple contexts (hiring decisions, leadership, and math performance) and stigmatized groups (women, ethnic minorities, female senators, and girls in Algebra). The importance of context, measurement type, and attitudes as moderators of evaluations and performance will be discussed.
Speaker: Anna S. Lau, Ph.D., Department of Psychology, University of California, Los Angeles
Topic: The cultural adaptation of evidence based treatments for minority families: Indications, strategies, and examples
Some experts contend that evidence-based treatments (EBTs) require cultural adaptation to be effective and relevant for minority families. However, critics argue there is insufficient data to warrant such adaptation and that minority families must be given access to EBTs delivered with fidelity. To inform this debate, Dr. Lau argues that cultural adaptation is best pursued when there is evidence that indicates the probability of treatment generalization failure. Cultural adaptation should itself be evidence based, with data driving one of three distinct strategies for adapting EBTs. These strategies involve adaptation of (1) therapy process to promote engagement, (2) augmentation of intervention content to target problems effectively, and (3) manipulation of treatment intensity to achieve lasting change. Each approach to cultural adaptation will be illustrated with examples from Parent Management Training. Preliminary data from a pilot trial of PMT with high-risk immigrant Chinese families will be used to illustrate the rationale underlying these competing approaches.
Speaker: Jeffrey Mio, Ph.D., Department of Psychology and Sociology, California State Polytechnic University, Pomona
Topic: Allies: Development, Experiences, and Effects
Mulitcultural psychologists have discussed the importance of allies for decades. However, what is an ally? What is their motivation for becoming an ally? What effects do allies have? What sustains their allied behavior? This presentation will discuss these issues as part of an empirical first step in addressing these questions.