Experimental challenges to theories of classical conditioning: application of an attentional model of storage and retrieval

Several studies have recently challenged the accuracy of traditional models of classical conditioning that account for some experimental data in terms of a storage deficit. Among other results, it has been reported that extinction of the blocking or overshadowing stimulus results in the recovery of the response to the blocked or overshadowed stimulus, backward blocking shows spontaneous recovery, extinction of the training context results in the recovery from latent inhibition, interposing a delay between conditioning and testing in latent inhibition increases latent inhibition, and latent inhibition antagonizes overshadowing. An existing neural network model of classical conditioning (N. A. Schmajuk, Y. Lam, & J. A. Gray, 1996), which includes an attentional mechanism controlling both storage and retrieval of associations, is able to quantitatively describe these results.     

Personality factors in relation to violent crimes

The personalities of a group of 54 persons (51 men and 3 women), imprisoned for the perpetration of violent crimes, were evaluated. The results were then compared to a normative group. This study considers personality factors and dimensions on three levels: (a) Basic factors: the "Big Five", (b) Personality disorders and clinical syndromes, (c) Personality dimensions related to personal wellbeing and social adaptation said to define a psychologically healthy individual. The results of the study show that it is not possible to define a basic personality profile for this group of violent delinquents based on the "Big Five" factors. It is, however, possible to find two habitual patterns of behaviour if the Millon Model (1990) is applied. These two behaviour patterns and attitudes towards life situations will be named "Dependent with compulsive traits" and "Psychopath tendencies". Both relate to indicators of mental health.     

Vocational choice and career planning. Spanish adaptation of Holland's Self-Directed Search (SDS-R)

The Self-Directed Search is a career-planning guide that works similarly to a vocational and professional interests inventory. A preliminary study allows detection of 68 ítems that need to be rectified, since they do not meet psychometric and semantic criteria. The current study demonstrates reliability and validity of the new adaptation. It is applied to a sample of 1460 subjects from different educational levels. As for reliability, the discrimination index of the items and internal consistency of the scales have improved. Additionally, procedures performed to verify validity (content, construct and concurrent) demonstrate that the instrument has acceptable validity. On balance, we can conclude that the instrument has sufficient scientific and technical credibility for application to the Spanish population.     

Anxiolytic-like activity of SB-205384 in the elevated plus-maze test in mice

Recent studies point to a major role for alpha2-containing GABA-A receptors in modulating anxiety. However, the possible implication of GABA-A receptors containing the alpha3 subunit on anxiety is less known. The aim of this study was to examine the effects of SB-205384 (0.5-4 mg/kg, i.p.), an alpha3 subunit positive modulator of GABA-A receptor, on anxiety tested in the elevated plus-maze in male mice, using classical and ethological parameters. Mice treated with SB-205384 showed an increase in the frequency of entries and the time spent in open arms, as well as a reduction in the time spent in closed arms, as compared with the control group. A notable increase of "head-dipping" unprotected and a reduction of "stretched-attend posture" protected was also evident. These findings indicate that SB-205384 exhibits an anxiolytic-like profile in the elevated plus-maze test, suggesting that GABA-A receptors which contain the alpha3 subunit might be involved in regulation of anxiety.     

Selective attention affects implicit and explicit memory for familiar pictures at different delay conditions

Three experiments investigated the effects of two variables -selective attention during encoding and delay between study and test- on implicit (picture fragment completion and object naming) and explicit (free recall and recognition) memory tests. Experiments 1 and 2 consistently indicated that (a) at all delays (immediate to 1 month), picture-fragment identification threshold was lower for the attended than the unattended pictures; (b) the attended pictures were recalled and recognized better than the unattended; and (c) attention and delay interacted in both memory tests. For implicit memory, performance decreased as delay increased for both attended and unattended pictures, but priming was more pronounced and lasted longer for the attended pictures; it was still present after a 1-month delay. For explicit memory, performance decreased as delay increased for attended pictures, but for unattended pictures performance was consistent throughout delay. By using a perceptual object naming task, Experiment 3 showed reliable implicit and explicit memory for attended but not for unattended pictures. This study indicates that picture repetition priming requires attention at the time of study and that neither delay nor attention dissociate performance in explicit and implicit memory tests; both types of memory require attention, but explicit memory does so to a larger degree.     

Pretend play: an application of an intervention program in autism

Methodologically and theoretically based on metarrepresentational deficit hypothesis, we design an intervention to teach the mental state of pretense to an autistic boy. The production and comprehension of symbolic play by means of the use of two specific strategies founded on pictorial analogy of the mental representation and process, was the focus of the learning. The efficiency and efectiveness of the program is reflected in the results that indicated the subject's competence to generate and comprehend the pretense as well as to generalize the acquired knowledge into other areas of mentalistic functioning. We discuss the possibility to develop a metarrepresentational knowledge based on the internalizing of the strategies of conceptual support.     

Relation availability was not confounded with familiarity or plausibility in Gagné and Shoben (1997): Comment on Wisniewski and Murphy (2005)

C. L. Gagné and E. Shoben (1997) proposed that the conceptual system contains information about how concepts are used to modify other concepts and that this relational information influences the ease with which concepts combine. Recently, E. J. Wisniewski and G. L. Murphy suggested that C. L. Gagné and E. Shoben's measure of relation availability was confounded with familiarity and plausibility and that the participants could simply retrieve the stored meanings of the phrases because the phrases were not novel. In this article, the authors demonstrate that E. J. Wisniewski and G. L. Murphy's plausibility and familiarity judgments are dependent variables that (a) are themselves responsive to changes in relation availability, (b) modifier relation availability predicts response time even when the influence of phrase familiarity and plausibility is controlled, and (c) the materials consisted of mainly novel phrases.     

Redundancy gain with static versus moving hands: a test of the hemispheric coactivation model

A simple reaction time (RT) experiment was conducted to test the hypothesis that redundancy gain arises partly because of hemispheric coactivation. Stimuli were presented to the left or right of fixation, or redundantly to both, and the participants had to make keypress responses as rapidly as possible to stimulus onset. A "static" condition, in which the participants held their hands at rest, was compared with a "dynamic" condition, in which they moved their hands back and forth in an oscillating motion prior to stimulus onset. As predicted from the hypothesis of hemispheric coactivation, redundancy gain, measured as the decrease in mean RT to redundant stimuli as compared with single stimuli, was smaller in the dynamic condition than in the static one.     

Why do adolescents use drugs? A common sense explanatory model from the social actor's perspective

Analysis was made of the common sense explanations of 60 Mexican teenage illicit drug users in rehabilitation to determine their drug use debut. The explanatory model was separated into three blocks, two of which contained common sense aspects: interaction between subject's plane and the collectivity; and relationship between subject's interior (subject-family) and exterior (environment or group-pressure). Based on these data, we propose that drug use debut may be linked to subjects' emotional vulnerability which originates in the family image and renders them more susceptible to the influence of others. This kind of reasoning points to a more passive than active, and more social than personal dynamic in drug use debut, important factors for developing preventative measures.