Selective delayed alternation deficits in dominantly inherited olivopontocerebellar atrophy

In order to characterize more completely the nature of the frontal lobe-type cognitive changes in patients with dominantly inherited olivopontocerebellar atrophy (OPCA) we administered two tasks sensitive to frontal system dysfunction, delayed alternation (DA) and delayed response (DR), to 12 patients from one OPCA family. Affected members from this family have previously been shown to have a marked and widespread cerebral (including frontal) cortical cholinergic reduction as severe as that observed in Alzheimer's disease. Performance on DA, but not on DR, was significantly impaired in the OPCA patients compared to that in the controls. We suggest that the DA deficits in OPCA could be a consequence of a loss of cholinergic innervation to orbitofrontal or possibly temporal cortical areas and/or damage to the integrity of the cerebello-frontal neuronal connections.     

Preimaginal induction of adult behaviour in insects

This review illustrates the role of preimaginal experiences in four main aspects of insect life: feeding, habitat choice, host selection, and social relationships. After an illustration of the two former aspects with examples taken from various species, special attention is paid to the two latter aspects. First, an experiment is described, which demonstrates the existence of preimaginal induction involved in host selection by the solitary parasitoid wasp Dinarmus basalis (Hymenoptera: Pteromalidae). Then, a review of preimaginal induction in ants' behaviour is presented; orientation of social behaviour, particularly altruism, is mainly determined by preimaginal imprinting. All the examples developed in this review clearly show that insects can no longer be considered as strictly, rigidly “pre-programmed” beings. Their complex behavioural development and plasticity is clearly documented.     

Processing of temporal duration information in working memory after frontodorsal tumour excisions

This study aimed to test the hypothesis that impairments of temporal duration processing after frontal lobe lesions reflect deficits in executive monitoring functions rather than a domain-specific deficit in the maintenance of duration information in working memory. Patients with frontodorsal lesions, clinical controls with post-central lesions, and healthy controls performed recognition and classification tasks, which should allow for testing maintenance and monitoring functions, respectively. Results showed mild non-selective impairments of the frontal patients on both temporal and spatial recognition tasks, but a marked selective degradation on temporal classification while performance on spatial classification was unimpaired. This suggests that maintenance of duration information in working memory after frontal lesions is basically preserved but that, depending on executive task characteristics, there is a specific deficit in the strategic organization of this type of information.     

Gender is a dimension of face recognition

In an experiment, the authors investigated the impact of gender categorization on face recognition. Participants were familiarized with composite androgynous faces labeled with either a woman's first name (Mary) or a man's first name (John). The results indicated that participants more quickly eliminated faces of the opposite gender than faces of the same gender than the face they were looking for. This gender effect did not result from greater similarity between faces of the same gender. Rather, early gender categorization of a face during face recognition appears to speed up the comparison process between the perceptual input and the facial representation. Implications for face recognition models are discussed.     

Priming visual face-processing mechanisms: electrophysiological evidence

Accumulated evidence from electrophysiology and neuroimaging suggests that face perception involves extrastriate visual mechanisms specialized in processing physiognomic features and building a perceptual representation that is categorically distinct and can be identified by face-recognition units. In the present experiment, we recorded event-related brain potentials in order to explore possible contextual influences on the activity of this perceptual mechanism. Subjects were first exposed to pairs of small shapes, which did not elicit any face-specific brain activity. The same stimuli, however, elicited face-specific brain activity after subjects saw them embedded in schematic faces, which probably primed the subjects to interpret the shapes as schematic eyes. No face-specific activity was observed when objects rather than faces were used to form the context. We conclude that the activity of face-specific extrastriate perceptual mechanisms can be modulated by contextual constraints that determine the significance of the visual input.     

Combined effect of goal setting and self-talk in performance of a soccer-shooting task

To examine the combined effect of goal setting and self-talk, 41 professional and semiprofessional soccer players from four different teams were tested on a soccer-shooting task. Teams were assigned to one of four conditions: (a) self-talk, (b) goal setting, (c) goal setting plus self-talk, and (d) do your best control. Subjects performed one baseline measurement and three experimental sessions. Analysis showed that performance, compared to the do your best condition, in the combined condition is immediately enhanced, whereas self-talk and goal-setting effects were significant from Session 3. No significant differences in performance were observed among experimental groups, except in Session 2, during which the combined group scored significantly better than the goal-setting group. It seems that, whereas both goal setting and self-talk are effective in enhancing performance, some advantage may be derived from a combined intervention. Findings are discussed in the perspective of past research efforts on goal setting and self-talk.     

Priming of non-speech vocalizations in male adults: the influence of the speaker's gender

Previous research reported a priming effect for voices. However, the type of information primed is still largely unknown. In this study, we examined the influence of speaker's gender and emotional category of the stimulus on priming of non-speech vocalizations in 10 male participants, who performed a gender identification task. We found a significant priming effect, which was greater for female than male vocalizations. In contrast, the emotional category of the stimuli did not appear to modulate the magnitude of priming. These data suggest that different aspects of the information conveyed in non-speech vocalizations may contribute differently to behavioral priming, possibly influenced by task relevance.     

On the lateralization of emotional prosody: an event-related functional MR investigation

In order to investigate the lateralization of emotional speech we recorded the brain responses to three emotional intonations in two conditions, i.e., "normal" speech and "prosodic" speech (i.e., speech with no linguistic meaning, but retaining the 'slow prosodic modulations' of speech). Participants listened to semantically neutral sentences spoken with a positive, neutral, or negative intonation in both conditions and judged how positive, negative, or neutral the intonation was on a five-point scale. Core peri-sylvian language areas, as well as some frontal and subcortical areas were activated bilaterally in the normal speech condition. In contrast, a bilateral fronto-opercular region was active when participants listened to prosodic speech. Positive and negative intonations elicited a bilateral fronto-temporal and subcortical pattern in the normal speech condition, and more frontal activation in the prosodic speech condition. The current results call into question an exclusive right hemisphere lateralization of emotional prosody and expand patient data on the functional role of the basal ganglia during the perception of emotional prosody.     

Semantic processing of words, cognitive resources and N400: an event-related potentials study

The specificity of the right hemisphere (RH) contribution to the semantic processing of words is still debated. Indeed, the semantic impairments of right hemisphere damaged (RHD) subjects may be the expression of limited general cognitive resources rather than a specific impairment of semantic processing ([Monetta et al., 2001]; [Murray, 2000]). The purpose of this study was to evaluate the possibility that the N400 reflect the availability of cognitive resources through an analysis of its different amplitudes according to different semantic complexity level. Ten young adults without any history of neurological damage participated in a semantic categorization task with two different levels of difficulty based on prototypicality. Event related potential (ERP) signals from 64 electrodes were recorded. An N400 was observed during the processing of difficult words and distractors. The results show that the greatest N400 activation was observed during the processing of difficult words, thus reflecting a possible increase in the amount of required cognitive resources.