Acute caffeine consumption enhances the executive control of visual attention in habitual consumers

Recent work suggests that a dose of 200–400 mg caffeine can enhance both vigilance and the executive control of visual attention in individuals with low caffeine consumption profiles. The present study seeks to determine whether individuals with relatively high caffeine consumption profiles would show similar advantages. To this end, we examined the effects of four caffeine doses (0 mg, 100 mg, 200 mg, 400 mg) on low- and high-level visual attention in individuals with high consumption profiles (n = 36), in a double-blind study using a repeated measures design. Results from the Attention Network Test indicated that caffeine enhanced both vigilance and the executive control of visual attention, but only at the highest administered dose (400 mg). We demonstrate that in habitual consumers high doses of caffeine can produce beneficial changes in visual attention. These results carry implications for the theorized interactions between caffeine, adenosine and dopamine in brain regions mediating visual attention.     

Binding across time: the selective gating of frontal and hippocampal systems modulating working memory and attentional states.

Temporal binding via 40-Hz synchronization of neuronal discharges in sensory cortices has been hypothesized to be a necessary condition for the rapid selection of perceptually relevant information for further processing in working memory. Binocular rivalry experiments have shown that late stage visual processing associated with the recognition of a stimulus object is highly correlated with discharge rates in inferotemporal cortex. The hippocampus is the primary recipient of inferotemporal outputs and is known to be the substrate for the consolidation of working memories to long-term, episodic memories. The prefrontal cortex, on the other hand, is widely thought to mediate working memory processes, per se. This article reviews accumulated evidence for the role of a subcortical matrix in linking frontal and hippocampal systems to select and "stream" conscious episodes across time (hundreds of milliseconds to several seconds). "Streaming" is hypothesized to be mediated by the selective gating of reentrant flows of information between these cortical systems and the subcortical matrix. The physiological mechanism proposed for this temporally extended form of binding is synchronous oscillations in the slower EEG spectrum (< 8 Hz).     

Psychometric analysis of the short-form UCLA Loneliness Scale (ULS-8) in Taiwanese undergraduate students

The main purpose of this study was to validate the short-form of the UCLA Loneliness Scale (ULS-8; Hays & DiMatteo, 1987) in Taiwanese undergraduate students. A total of 130 undergraduate students participated in this study. Participants completed the ULS-8 in addition to measures of life satisfaction, social support, and adult attachment style. Result of confirmatory factor analysis supported the one-factor model of the ULS-8 with adequate values of various fit indices, revealing that the 8 items of the scale were homogeneous for measuring loneliness. In addition, the ULS-8 had a negative relationship with life satisfaction, and social support; and a positive one with anxiety and avoidant attachment tendency. All the findings showed that the ULS-8 was an adequate short-form measure of loneliness.     

Psychological group memberships as outcomes of resource distributions

We propose that people can and will infer group memberships from resource distributions, and that these distributions have implications for people's understandings of the groups themselves and their own associations with these groups. We derive hypotheses from social identity and self‐categorization theories, and test them in three experiments. In Experiment 1, participants systematically rated specific patterns of group memberships as more likely than others in light of specific resource distributions in a manner consistent with our predictions. In Experiment 2, intragroup distributive fairness led to greater perceived self‐in‐group similarity than intra‐group distributive unfairness, while distributively unfair, in‐group favouritism led to greater perceived self‐in‐group similarity than intergroup fairness. In Experiment 3, social identification dropped following unfair, out‐group favouritism and intragroup unfairness, but not unfair, in‐group favouritism, or intragroup and intergroup fairness. The current data provide support for our hypotheses and clear evidence that resource distributions can be providers of group membership information. Copyright © 2007 John Wiley & Sons, Ltd.     

Training clinical psychologists for rural and northern practice: Transforming challenge into opportunity

Abstract: The Rural and Northern Program (R&NP) of the University of Manitoba's Department of Clinical Health Psychology (DCHP) is a unique training and service delivery platform that was developed in response to the scarcity of psychological services in rural and northern areas of the province of Manitoba, Canada. Since 1996 rural and northern‐based psychologists, in conjunction with the faculty based in Winnipeg (Manitoba's largest city) have offered training to two interns and one postdoctoral resident (resident) yearly. The current article discusses the nature of the program, the regions of Manitoba that the program services, and recruitment and retention data. The authors conclude by offering suggestions for creating sustainable rural/northern psychological practice.     

Concurrent validity in Taiwan of the Comprehensive Developmental Inventory for Infants and Toddlers who were full-term infants

This study investigated the concurrent validity of the Comprehensive Developmental Inventory for Infants and Toddlers (CDIIT) with the Bayley Scales of Infant Development-II (BSID-II) in full-term infants. 106 full-term infants ages 6 to 18 months (63 boys, 43 girls) were recruited as a convenience sample. One tester administered the CDIIT and BSID-II to all children. The Developmental Ages and Developmental Quotients of the motor and the mental scales from both tests were analyzed with Pearson correlations and quadratic weighted kappa tests. The results showed that correlation coefficients for Developmental Ages between both tests on cognitive and motor subtests were high (r = .91-.95) and for Developmental Quotients were moderate (r = .57-.67). Moderate classification agreement was found in the two scales (quadratic weighted kappa = .50-.53). Developmental Quotients classification for the CDIIT tended to be a little higher than for the BSID-II. It was concluded that although acceptable concurrent validity was found for the Motor and Cognitive subtests of the CDIIT, the tester should be cautious to compare Developmental Quotients obtained from the above two tests in clinical or in research settings.     

Analysis of social interaction gestures in infants with autism.

This study analyzes the emergent use of gestures used among 9-12-month-old infants with autism and typical development using retrospective video analysis. The purpose of the present investigation was to examine the frequency, initiation, prompting, and diversity of types of gestures used for social interaction purposes. It was hypothesized that a restricted variety in type(s) of gestures as well as fewer child-initiated gestures and more prompted gestures would be associated with later diagnosis of autism. Logistic regression analysis found that decreased variety in type of gestures used was significantly associated with autism status. Neither number of total gestures nor initiation of gestures (child-initiated vs. prompted) was significantly associated with autism status.     

Internet access and use among homeless and indigent drug users in Long Beach, California.

There has been a growing interest in using the Internet to access a variety of populations for prevention education and health care. It is not clear that this is viable for homeless and other marginalized populations. The purpose of this study was to describe Internet access and use among a sample of homeless and indigent drug users. A brief questionnaire was developed to assess computer ownership, use, email, and Internet access and use. Participants were recruited through a community-based human immunodeficiency virus (HIV) prevention program. 265 participants completed the questionnaire. While 55% had ever used a computer in their lifetime, only 25% had ever owned a computer, 24% had ever had their own email account, 33% had access to a working computer in the last 30 days, 10% had sent or received email in the last 30 days, and 19% had surfed or accessed information on the Internet in the last 30 days. Logistic regression predicting lifetime use of a computer showed predictive factors of having completed high school (Odds Ratio [OR] = 4.5; 95% Confidence Interval [CI] = 2.41, 8.38) and number of days used amphetamines in the last 30 days, per 5 days of use (OR = 1.64; 95% CI = 1.18, 2.27). Inversely related were age, per 5 years of age (OR = 0.78; 95% CI = 0.65, 0.93) and number of days used marijuana in the last 30 days, per 5 days of use (OR = 0.97; 95% CI = 0.76, 0.99). Very low access and usage suggest that Internet-based public health education models be reexamined for this population. The association with amphetamine use may indicate a facilitating effect of amphetamine by heightening awareness and increasing wakefulness.     

Parsing the relations between SES and stress reactivity: examining individual differences in neonatal stress response

In an effort to further delineate the reported relations between socioeconomic status (SES) and stress reactivity in children, associations between three domains of perinatal risk: socio-demographic, obstetrical complications, and maternal psychological factors during the perinatal period, and cortisol and behavioral reactivity were examined in 100 healthy African American neonates whose families resided in low-income environments. Behavioral and cortisol response to a heel stick and the Neonatal Behavioral Assessment Scale (NBAS) was measured within the first 2 days of life. Significant associations were found between socio-demographic risk, obstetrical complications, and maternal psychological factors and neonatal behavior and cortisol in the context of the NBAS; few significant associations were found in the context of the heel stick. Greater magnitude of perinatal risk was associated with both higher and lower than average neonatal stress reactivity. The results provide preliminary data on the types of perinatal experiences that may have significant effects on stress reactivity in humans, especially in the context of families living in poverty. Application of these data to the hypothesis that prenatal stress results in programming of the fetal/neonatal stress response system is discussed.     

Deconstructing executive deficits among persons with autism: implications for cognitive neuroscience

Individuals with autism demonstrate impairments on measures of executive function (EF) relative to typically developing comparison participants. EF is comprised of several processes including inhibition, working memory and set shifting that develop throughout the lifespan. Impairments in EF may appear early in development and persist, or may represent a more transient delay which resolves with time. Given the unevenness of the cognitive profile of persons with autism, understanding the development of EF poses methodological challenges. These issues include those related to matching measures and the choice of comparison participants to which the performance of persons with autism will be compared. In the current review, we attempt to break down the processes of inhibition, working memory and set shifting among persons with autism. We propose to do this within a developmental perspective that highlights how matching measures and comparison participants can affect the interpretation of research findings.