Establishing Arbitrary Stimulus Classes via Identity-matching Training and Non-reinforced Matching with Complex Stimuli

The present study investigated whether training on an identity match-to-sample task followed by non-reinforced matching probes with complex stimuli leads to the emergence of multiple arbitrary matching performances and arbitrary stimulus classes in preschool children. In Experiment 1, eight subjects were trained on a colour-matching task (A-A). Then they received tests with complex AB and AC colour-form stimuli (AB-A, B-AB; AC-A, C-AC). These tasks were designed to help subjects respond to both elements of each complex stimulus. Subsequent B-A, C-A, A-B, A-C, B-C, and C-B tests revealed that all subjects had acquired class-consistent colour-form and form-form relations. Experiment 2 examined whether these results could be replicated when subjects were encouraged to respond to the colour elements of some (AB) complex stimuli and to the form elements of other (AC) stimuli. The procedures were the same as in Experiment 1 except that during the first test only A-AB and C-AC tasks were used. Six of eight subjects demonstrated all tested relations.     

Posttraumatic Symptoms, Functional Impairment, and Coping among Adolescents on Both Sides of the Israeli–Palestinian Conflict: A Cross-Cultural Approach

This study assessed the effects of the ongoing violence on the mental health of Palestinian and Israeli youths. Parallel instruments were developed and adapted, as part of a collaborative project, in order to assess, in each society: (1) differential rates of exposure to the conflict, (2) the association between exposure and the severity of posttraumatic symptoms (PTS), and (3) the inter‐relationships among PTS, functional impairment, somatic complaints, and coping strategies. Participants were 1,016 Israeli and 1,235 Palestinian adolescents. A self‐report questionnaire assessed exposure. PTS was measured using the UCLA PTSD Reaction Index, functional impairment and somatic complaints were measured with the DISC, and coping strategies were assessed with Brief Cope. In both societies, greater exposure to conflict‐related violence was associated with more PTS and more somatic complaints, with girls reporting more distress than boys. A total of 6.8 per cent of the Israeli students and 37.2 per cent of the Palestinian students met criteria for Post Traumatic Stress Disorder (PTSD). In both societies, but more pronounced in the Palestinian Authority, adolescents reported significant levels of functional impairment, mainly in the area of school functioning. Students with PTSD reported more somatic complaints as well as greater functional impairment. The results show the serious psychological impact of the ongoing violent conflict on Israeli and Palestinian students and point to the need to develop appropriate school‐based interventions to address their mental health needs. Cette étude évalue les effets de la violence continuelle sur la santé mentale des jeunes palestiniens et israéliens. Des instruments analogues ont été développés et adaptés, dans le cadre d’un projet de collaboration, afin d’évaluer dans chaque société: (1) les différences de taux d’exposition au conflit, (2) l’association entre l’exposition et la sévérité des symptômes post‐traumatiques (PTS) et (3) les interrelations entre les PTS, les troubles fonctionnels, les plaintes somatiques et les stratégies de faire‐face. 1016 adolescents israéliens et 1235 adolescents palestiniens ont participéà cette étude. Un questionnaire auto‐administré mesure l’exposition au conflit. Les PTS sont mesurés par l’utilisation de l’UCLA PTSD Reaction Index, les troubles fonctionnels et les plaintes somatiques sont approchés par le DISC, et les stratégies de faire‐face par le Brief Cope. Dans les deux sociétés, une plus grande exposition au conflit et à ses violences est associée à des PTS plus importants et à plus de plaintes somatiques, les filles manifestant plus de détresse que les garçons. Un total de 6.8% des étudiants israéliens et 37.2% des étudiants palestiniens répondent à des critères du Post Traumatic Stress Disorder (PTSD). Dans les deux sociétés, mais de façon plus prononcée dans l’Autorité palestinienne, les adolescents rapportent des niveaux significatifs de troubles fonctionnels, principalement dans le domaine du fonctionnement scolaire. Les étudiants avec PTSD manifestent plus de plaintes somatiques, il en va de même pour les troubles fonctionnels. Les résultats montrent le sérieux impact psychologique d’un conflit violent et continuel sur les étudiants israéliens et palestiniens et signale le besoin de développer des interventions scolaires appropriées à leurs besoins en matière de santé mentale.     

Defensive and offensive behaviours in a Kleefstra syndrome mouse model

Animal Cognition - Kleefstra syndrome in humans is characterized by a general delay in development, intellectual disability and autistic features. The mouse model of this disease (Ehmt1±)...     

DIVISION OF HOUSEHOLD LABOR, STRAIN, AND DEPRESSIVE SYMPTOMS AMONG MEXICAN AMERICANS AND NON-HISPANIC WHITES

This article presents preliminary tests of the hypothesis that household labor serves as a source of strain and is indirectly associated with depressive symptoms. It also examines associations of gender and Mexican-American ethnicity with housework, household strain, and depressed mood. Respondents are 668 Mexican Americans and 394 non-Hispanic whites. Because respondents are randomly selected community residents and are married, average strain and depressive symptom levels are low. Results are consistent with the hypothesis that housework affects depressed mood indirectly, through household strain. Among women, housework is associated with an increased likelihood of household strain, which, in turn, is associated with depressive symptoms. Among men, housework is unrelated to household strain, but household strain is associated with depressed mood. Although ethnicity and gender are associated with household division of labor, with more traditional patterns among Mexican Americans, ethnicity does not modify associations among housework, household strain, and depressive symptoms.     

Emergent conditional discrimination in children: Matching to compound stimuli

This study reports two experiments that first taught preschool children identity-matching to compound sample and compound comparison stimuli. A compound stimulus consisted of a colour and a form superimposed on one another. Test sessions assessed whether children related the form and colour elements of a particular compound stimulus. The test for this was matching to sample in which an arbitrary conditional discrimination was required. A majority of the children selected the correct colour comparison in the presence of each form sample. The children also showed the reverse sample-comparison relations: they matched form comparisons to the corresponding colour samples, respectively. In the context of these arbitrary relations, new colours were paired with the form elements of the samples (Experiment 1), and new form elements were paired with the colour elements of the comparisons (Experiment 2). Subsequent tests assessed whether the new stimulus elements had control over responding when presented as single samples or comparisons. Test results showed that most subjects were able to relate the new stimulus elements to the corresponding colour and form elements, respectively. The study demonstrated that matching to compound stimuli in training and testing conditionsMaygenerate conditional relations between the individual stimulus elements.