The influence of semantic and morphological complexity of verbs on sentence recall: Implications for the nature of conceptual representation and category-specific deficits

One hundred and forty normal undergraduate students participated in a Proactive Interference (PI) experiment with sentences containing verbs from four different semantic and morphological classes (lexical causatives, morphological causatives, and morphologically complex and simplex perception verbs). Past research has shown significant PI build-up effects for semantically and morphologically complex verbs in isolation (de Almeida & Mobayyen, 2004). The results of the present study show that, when embedded into sentence contexts, semantically and morphologically complex verbs do not produce significant PI build-up effects. Different verb classes, however, yield different recall patterns: sentences with semantically complex verbs (e.g., causatives) were recalled significantly better than sentences with semantically simplex verbs (e.g., perception verbs). The implications for the nature of both verb-conceptual representations and category-specific semantic deficits are discussed.     

School Context and Genetic Influences on Aggression in Adolescence

Genetic and environmental contributions to variation in aggression were examined using adolescents' self-reports of aggressive behavior. The National Longitudinal Study of Adolescent Health provided a sample of 1,515 pairs of adolescents in five genetically informative groups (i.e., monozygotic twins, dizygotic twins, full siblings, half siblings, and unrelated siblings reared together). The analysis, a DeFries-Fulker regression within a hierarchical linear model, yielded findings on individual-level heritability (h2), shared environmental effects (c2), school-level effects, and school-level moderation of h2 and c2. The estimate of h2 for aggression in the full sample was .32, and c2 was .05. In the moderating effect, h2 increased and c2 decreased with greater school-level family warmth. Two effects on school means were found: Those schools with greater ethnic-racial heterogeneity had higher mean levels of aggression, and schools where students perceived greater family warmth had lower mean levels of aggression.     

Ambiguous novel compounds and models of morphological parsing.

This paper reports on two experiments that investigated the activation of morphemes in English novel compounds. All experiments employed stimuli that we have called "ambiguous novel compounds." These words (e.g., clamprod) have two interpretable parses (e.g., clam + prod or clamp + rod) and thus offer an opportunity to investigate which parses are preferred, whether both possible parses are computed, and whether parsing procedures "divide" words into their morphological constituents or "extract" constituent representations. The results suggest that morphological parsing does not simply divide a word into its constituents, but rather generates multiple representations that are subsequently evaluated.     

Memory modulation by post-training intraperitoneal, but not intracerebroventricular, administration of ACTH or epinephrine

Post-training introparitoneal (ip) administration of ACTH1-24 (25 ng/rat) or epinephrine HCl (625 ng/rat) facilitated retention of a step-down inhibitory avoidance task acquired using a small start platform (5-cm high, 25 X 7 cm) and a low intensity training footshock (0.3 mA, 60 Hz), and caused retrograde amnesia for a similar task acquired using a large platform (5-cm high, 25 X 25 cm) and a high intensity training footshock (0.8 mA, 60 Hz). The post-training intracerebroventricular (icv) administration of 5, 25, or 125 ng/rat of ACTH or of 5, 25, 125, 625, or 1250 ng/rat of epinephrine had no effect on retention of either task. These findings suggest that memory modulation by ACTH and epinephrine is mediated by reflexes initiated at peripheral receptors that affect brain activity during the post-training period.     

Effect of age and gender in the control of elbow flexion movements

In previous studies of rapid elbow movements in young healthy men, characteristic task-dependent changes in the patterns of muscle activation when movement speed or distance was varied have been reported. In the present study, the authors investigated whether age or gender is associated with changes in the patterns of muscle activity previously reported in young men. Arm movements of 10 healthy older and 10 healthy younger participants (5 men and 5 women in each group) were studied. Surface electromyograms (EMGs) from agonist (biceps) and antagonist (triceps) muscles, kinematic and kinetic parameters, as well as anthropometric and strength measures were recorded. All 4 groups of participants showed similar task- (distance or speed) dependent changes in biphasic EMG activity. Similar modulation of the initial rate of rise of the EMG, integrated agonist and antagonist EMG activity, as well as their relative timing were observed in all 4 groups. Those results suggest that older individuals of both genders retain the control strategies for elbow movements used by young individuals. Despite the qualitative similarities in the patterns of muscle activation, the men moved more quickly than the women, and younger participants moved more quickly than older participants. Those performance differences could not be explained in terms of differences in body size and strength alone.     

A Study of the Ethical Dilemmas Experienced by School Psychologists in Portugal

This study examines the ethical dilemmas and difficulties encountered by Portuguese school psychologists. As part of a larger survey, participants were asked about ethical issues faced in daily practice and asked to describe ethical incidents. Of the 477 respondents, 274 reported 441 ethically troubling or challenging situations. Responses were coded into a six-category system based on the code of ethics of Portuguese psychologists. Most of the reported dilemmas concerned privacy and confidentiality principles (53%). Results are discussed in light of relevant literature and international findings. Implications for the development of the profession and future research are provided.