Effects of subchronic administration of gammahydroxybutyrate (GHB) on spatial working memory in rats

GHB, a popularly known drug as "liquid ecstasy", is a substance with abuse potential. Among the possible described side-effects after the continued consumption of GHB are amnesia and deterioration of memory. Likewise, recent studies indicate the existence of neurotoxicity in certain brain regions after its prolonged treatment. The aim of this study was to examine the effect of the subchronic administration of GHB (10 and 100 mg/kg) on spatial memory and sensoriomotor reflexes in male rats, using the Morris water maze and a battery of sensoriomotor tests, respectively. The results indicated that animals treated with GHB (10 mg/kg) showed a greater latency of escape during the phase of acquisition in the days first and third of tests, as compared with the control group (p<0.05), as well as a deterioration of grasping reflex with the two doses of GHB (p<0.01). Numerous studies indicated that the medial prefrontal cortex is a crucial neuronal substrate in the working memory and grasping reflex modulation. These results suggest that prolonged administration of GHB could alter structure and/or function of the medial prefrontal cortex, as well as its interconnections with other brain regions involved in the evaluated cognitive and neurological processes.     

Building Interdisciplinary/Intersectoral Research Partnerships for Community-Based Mental Health Research with Older Minority Adults

Community-based research often brings investigators from different disciplinary backgrounds together with community representatives to conduct research on topics of mutual concern. This paper describes a case example that illustrates an interdisciplinary/intersectoral study of depression and barriers to mental health care among older adults and illustrate the factors central to implementing a successful research partnership. It will address the following conditions that facilitate and challenge interdisciplinary/intersectoral research: (1) achieving commonality of purpose in study design and research and referral approaches; (2) ensuring the ability to develop, field-test and implement psychometrically rigorous and culturally and qualitatively appropriate instruments; (3) building effective management structures for interdisciplinary/intersectoral research partnerships; and (4) identifying, training and supporting qualified researchers to carry out a mental health study with older ethnically diverse adults. The paper concludes with strengths and limitations of the approach.     

Neuropsychological evidence for "word-meaning deafness" in a Spanish-speaking patient

In this paper we present a case of "word-meaning deafness," characterised by serious problems in the comprehension of spoken language, whilst repetition and writing words and non-words from dictation are preserved. This performance indicates the impossibility of correctly accessing phonological representation from the semantic representation of words. Neuropsychological evidence on specific alterations in word-meaning disorders is scarce, and this study contributes new findings with a Spanish-speaking patient. The nature of the processes involved in understanding language and the cerebral mechanisms that might be affected in each case were discussed, in accordance with current neuropsychological theories.     

Fragment difficulty in priming on word-completion tests

Word-fragment completion is a frequently used test in implicit memory research. In this test priming is the relevant variable. Priming is obtained by subtracting the proportion of nonstudied word fragments correctly completed (called "completion difficulty baseline") from the studied word fragments correctly completed. Since completion difficulty can spuriously vary greatly between experimental conditions, its effect on magnitude of priming is studied. Normative frequency of occurrence of target words was considered because their influence over performance is known. In an experiment using a word-fragment completion test, participants' completion of fragments at three levels of completion difficulty and two levels of frequency was tested. Analysis showed that completion difficulty had a significant effect on global priming. The priming magnitude was higher for Difficult and Moderately Difficult fragments than for Easy ones. An interaction between fragment difficulty and normative word frequency was observed. When the fragments were easy to complete, the expected effect of higher priming for low-frequency words than for high-frequency words was not observed.     

Optimization of sample size in controlled experiments: The CLAST rule

Sequential rules are explored in the context of null hypothesis significance testing. Several studies have demonstrated that the fixed-sample stopping rule, in which the sample size used by researchers is determined in advance, is less practical and less efficient than sequential stopping rules. It is proposed that a sequential stopping rule called CLAST (composite limited adaptive sequential test) is a superior variant of COAST (composite open adaptive sequential test), a sequential rule proposed by Frick (1998). Simulation studies are conducted to test the efficiency of the proposed rule in terms of sample size and power. Two statistical tests are used: the one-tailed t test of mean differences with two matched samples, and the chi-square independence test for twofold contingency tables. The results show that the CLAST rule is more efficient than the COAST rule and reflects more realistically the practice of experimental psychology researchers.     

Father responsivity: couple processes and the coconstruction of fatherhood

Forty in-depth interviews of heterosexual parents of children 5 five years of age and younger are analyzed using a qualitative grounded theory approach to understand how couples coproduce fatherhood within their day-to-day relationships and in social, cultural, and economic contexts. The analysis identifies the construct "responsivity" as a central process through which, to varying degrees, fathers are aware of the needs of their wives and children and able to take an active part in meeting them. Three groups of fathers are examined according to their level of responsivity: low, moderate, and high. Factors influencing degree of father responsivity include gender constructions, power and the wife's influence, attunement, work schedules, and emotional tradeoffs. Implications for practice are suggested.     

Evaluating risk factors in relation to preschool social–emotional skills using a person-centred approach

Few studies have utilised a person-centred approach when it comes to understanding risk factors in young children. The present study uses this type of approach while examining risk factors in relation to social–emotional skills. Parent reports for 444 preschool-aged children disclosed each child's exposure to eight different risk factors, as well as their social–emotional abilities. A latent class analysis was utilised to examine subgroups of risk, rather than using a cumulative approach, to see whether specific risk factors differentiated participants. Subgroup differences in distal social–emotional skills were then examined. The subgroup with systemic, economic and parent stress risk factors showed the lowest social–emotional abilities, in comparison to subgroups with only systemic or a combination of systemic and economic risks. These results suggest that addressing parent stress may be particularly relevant when considering children's social–emotional development. Implications for interventions and clinical practice are discussed.     

The perceived vulnerability to disease scale: Cross-cultural measurement invariance and associations with fear of COVID-19 across 16 countries

Using cross-sectional data from N = 4274 young adults across 16 countries during the COVID-19 pandemic, we examined the cross-cultural measurement invariance of the perceived vulnerability to disease (PVD) scale and tested the hypothesis that the association between PVD and fear of COVID-19 is stronger under high disease threat [that is, absence of COVID-19 vaccination, living in a country with lower Human Development Index (HDI) or higher COVID-19 mortality]. Results supported a bi-factor Exploratory Structural Equation Modeling model where items loaded on a global PVD factor, and on the sub-factors of Perceived Infectability and Germ Aversion. However, cross-national invariance could only be obtained on the configural level with a reduced version of the PVD scale (PVD-r), suggesting that the concept of PVD may vary across nations. Moreover, higher PVD-r was consistently associated with greater fear of COVID-19 across all levels of disease threat, but this association was especially pronounced among individuals with a COVID-19 vaccine, and in contexts where COVID-19 mortality was high. The present research brought clarity into the dimensionality of the PVD measure, discussed its suitability and limitations for cross-cultural research, and highlighted the pandemic-related conditions under which higher PVD is most likely to go along with psychologically maladaptive outcomes, such as fear of COVID-19.     

A COMPARISON OF REINFORCER ASSESSMENT METHODS: THE UTILITY OF VERBAL AND PICTORIAL CHOICE PROCEDURES

We compared three methods of stimulus preference assessment for verbal children and specifically evaluated the utility of a verbal choice procedure for assessing relative reinforcer value. Using a token system, relative preference for five categories of reinforcers, representing 15 different stimuli, was assessed by three methods: a reinforcer survey, a verbal stimulus-choice questionnaire, and a pictorial stimulus-choice procedure. Results showed that the verbal and pictorial stimulus-choice assessments accurately identified high- and low-preference categories for 3 of 4 participants. Survey results alone often rated multiple categories as high preference, were less likely to identify low-preference categories, and were less likely to correspond with the results of a reinforcer assessment.     

THE DIFFERENTIAL EFFECTS OF TEACHER AND PEER ATTENTION ON THE DISRUPTIVE CLASSROOM BEHAVIOR OF THREE CHILDREN WITH A DIAGNOSIS OF ATTENTION DEFICIT HYPERACTIVITY DISORDER

We conducted functional analyses of classroom disruption during contingent teacher and peer attention conditions for 3 children with attention deficit hyperactivity disorder. Attention provided by peer confederates appeared to function as a distinct form of positive reinforcement for all 3 children.