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141.
142.
The mechanisms of extinction were examined by reducing the intensity of the unconditioned stimulus (US) after acquisition training to determine whether such reductions lie on a continuum with CS-alone extinction. The experiments revealed that reductions in US intensity yielded extinction-like effects. Specifically, there were proportional reductions in the daily mean level of responding across sessions. There were also persistent within-session declines and between-session increases of responding analogous to spontaneous recovery. Surprisingly, even when US intensity was held constant, within-session declines and between-session increases were apparent. The results are discussed with respect to possible contributions from unlearning, new learning, generalization decrement, and nonassociative loss, especially CS-specific attentional changes and CR-specific reactive inhibition. 相似文献
143.
This experiment investigated whether phonological priming of syllables helps resolve tip-of-the-tongue (TOT) states in young and older adults. Young, young-old, and old-old adults read general knowledge questions and responded "know," "TOT," or "don't know" accordingly. Participants then read a list of 10 words that included 3 phonological primes corresponding solely to the first, middle, or last syllable of the target word. Young and young-old adults resolved more TOTs after first-syllable primes, but old-old adults showed no increase in TOT resolution following any primes. These results indicate that presentation of the first syllable of a missing word strengthens the weakened phonological connections that cause TOTs and increases word retrieval, but not for old-old adults who experience greater deficits in the transmission of priming across these connections. 相似文献
144.
This article reviews relevant literature as to the labor pool of qualified individuals with disabilities and employment in information technology (IT) sector jobs. First, the article reviews the empirical literature on barriers to employment in IT for persons with disabilities. The examination then is extended to studies of barriers to employment for individuals with disabilities in other employment sectors. Findings illustrate the limited experiences that IT and non-IT companies have in employing and accommodating employees with disabilities. Implications are discussed for enhancing the employment of qualified workers with disabilities in IT through research, education, training, and mentoring programs. 相似文献
145.
The objective of this research was to test substance-related and non-substance-related psychiatric disorders as predictors of attempted suicide among adolescents. Ninety-six psychiatrically disordered suicide attempters were matched one-to-one to 96 psychiatrically disordered non-attempters on age, race, gender, and the presence/absence of major depression. Conditional logistic regression was used to test psychiatric risk factors for their power to predict attempted suicide among adolescents. Bipolar disorder, cocaine use disorders, and conduct disorder were found to be predictive of attempted suicide in univariate testing. Bipolar disorder, inhalant use disorders, cocaine use disorders, and hallucinogen use disorders were found to be predictive of attempted suicide, after adjusting for all other covariates. Loglinear analyses revealed high odds ratios associated with the comorbidities of alcohol use disorder with conduct disorder and drug use disorders with conduct disorder in both groups. Higher rates of cocaine use disorder/conduct disorder, hallucinogen use disorder/conduct disorder, and alcohol use disorder/ conduct disorder were found among suicide attempters. Evaluation of these particular comorbid conditions should be part of the adolescent suicide risk assessment. 相似文献
146.
Kevin?D.?BeckEmail author Francis?X.?Brennan Richard?J.?Servatius 《Integrative psychological & behavioral science》2002,37(2):128-139
In this study we assessed habituation and sensitization of the acoustic startle response (ASR) to discern whether intense,
inescapable stress affects nonassociative learning differently in male and female rats. Rats were inescapably stressed 2 hours
per day over 3 consecutive days. ASR magnitudes were measured at several times post-stress (1, 4, 8, and 15 days after cessation).
Females generally showed greater ASR magnitudes (compared to males), but both sexes exhibited short and long-term habituation
across the testing days. ASR magnitudes were only affected by stress in male subjects. The effect in males was an increase
in short-term sensitization of the ASR on post-stress day-4. The results suggest that stressed males and females react differently
to ASR testing, in that stress males appear to develop an exaggerated ASR response over repeated test sessions due to short-term
sensitization. The source of the short-term sensitization is discussed with regards to possible stress-induced enhanced contextual
learning during ASR testing on post-stress day-1. 相似文献
147.
148.
Kurtz DB Sheehe PR Kent PF White TL Hornung DE Wright HN 《Perception & psychophysics》2000,62(5):1121-1129
Perceptual spaces, in which similar stimuli are located close to each other and dissimilar stimuli are located far apart, have aided in the understanding of the physiological and psychological bases for sensory quality coding. Differences in perception between individuals should be reflected by differences in the spatial relationships between stimuli. If the dimensionality of the perceptual space is small (e.g., color space), individual differences that reflect specific pathologies are readily apparent from visual inspection. On the other hand, if the dimensionality of the perceptual space is large (as is proposed for odor space), visual inspection alone may not reveal individual differences in quality perception. The present work presents an information-theory-based method for quantifying individual differences in quality perception from perceptual confusion matrices. The ability of this method to quantify individual differences in quality perception is shown in a hypothetical example of specific anosmia. Finally, the method is applied to the examination of intrasubject consistency of odorant quality perception. 相似文献
149.
The rapid detection of facial expressions of anger or threat has obvious adaptive value. In this study, we examined the efficiency of facial processing by means of a visual search task. Participants searched displays of schematic faces and were required to determine whether the faces displayed were all the same or whether one was different. Four main results were found: (1) When displays contained the same faces, people were slower in detecting the absence of a discrepant face when the faces displayed angry (or sad/angry) rather than happy expressions. (2) When displays contained a discrepant face people were faster in detecting this when the discrepant face displayed an angry rather than a happy expression. (3) Neither of these patterns for same and different displays was apparent when face displays were inverted, or when just the mouth was presented in isolation. (4) The search slopes for angry targets were significantly lower than for happy targets. These results suggest that detection of angry facial expressions is fast and efficient, although does not "pop-out" in the traditional sense. 相似文献
150.