Norme de motivation intrinsèque et utilité sociale : recherches dans le champ organisationnel

Numerous theoretical models have been proposed to explain motivation in organizational settings. Several authors such as Herzberg, Deci and Ryan distinguish between intrinsic and extrinsic motivation. A new approach to intrinsic motivation (François, 2003) is now developping in France. It consists of considering that “intrinsic motivation” is a social norm. We have tested the normativity of intrinsic motivation in two field studies using the judge's paradigm. The first study was conducted on 52 recruiters, the second was conducted on 25 experts evaluating a project concerning the creation of an organization. Results show that evaluators prefered intrinsically motivated than extrinsically motivated candidates in both studies. Finally evaluators used utilitarians traits to describe intrinsically motivated candidates. This result gives force to a normative interpretation of intrinsic motivation.     

Renewal of cue-elicited urge to smoke: implications for cue exposure treatment

The effects of cue exposure therapy are limited, because renewal after extinction is an important source of relapse. In this study, 33 smokers were exposed to a cue predicting smoking availability and a cue predicting smoking unavailability in one context (acquisition context A). Following extinction in another context (extinction context B), a test for renewal took place in the original acquisition context A (i.e. ABA renewal). Urge to smoke was measured using a Visual Analogue Scale. Renewal of differential conditioned urge responding occurred when participants were tested in the acquisition context, while differential urge responding remained extinguished when tested in the extinction context. This experiment provides evidence that ABA renewal occurred in smokers. Clinical implications are discussed.     

WISC-R subtest but no overall VIQ-PIQ difference in Dutch children with PDD-NOS

VIQ-PIQ differences have been studied in children with autism and Asperger syndrome but have not been studied in a separate group of children with PDD-NO, although, PDD-NOS has a much higher prevalence rate than autism and deficits in communication and social interaction are severe. The Wechsler Intelligence Scale for Children-Revised (WISC-R) was administered to 100 children, aged 6-12 years, with PDD-NOS (n = 76), autism (n = 13), and Asperger syndrome (n = 11). PDD-NOS was diagnosed using explicit research criteria. No overall differences between VIQ and PIQ were found in PDD-NOS and autism. Peaks in the subtest scores on Information, Similarities, Picture Arrangement, and Mazes, and troughs in the subtest scores on Comprehension, Digit Span, and Coding were demonstrated in children with PDD-NOS. Their score on the Freedom from Distractibility factor was lower than the scores on the Verbal Comprehension factor and the Perceptual Organization factor. Children with PDD-NOS seemed to have a similar VIQ-PIQ profile as children with autism, and on the subtest level children with PDD-NOS showed some similarities to children with Asperger syndrome or autism. It was not possible to distinguish PDD-NOS from autism or Asperger syndrome by using IQ scores.     

Meditation states and traits: EEG, ERP, and neuroimaging studies

Neuroelectric and imaging studies of meditation are reviewed. Electroencephalographic measures indicate an overall slowing subsequent to meditation, with theta and alpha activation related to proficiency of practice. Sensory evoked potential assessment of concentrative meditation yields amplitude and latency changes for some components and practices. Cognitive event-related potential evaluation of meditation implies that practice changes attentional allocation. Neuroimaging studies indicate increased regional cerebral blood flow measures during meditation. Taken together, meditation appears to reflect changes in anterior cingulate cortex and dorsolateral prefrontal areas. Neurophysiological meditative state and trait effects are variable but are beginning to demonstrate consistent outcomes for research and clinical applications. Psychological and clinical effects of meditation are summarized, integrated, and discussed with respect to neuroimaging data.     

Aging and the perception of 3-D shape from dynamic patterns of binocular disparity

In two experiments, we investigated the ability of younger and older observers to perceive and discriminate 3-D shape from static and dynamic patterns of binocular disparity. In both experiments, the younger observers' discrimination accuracies were 20% higher than those of the older observers. Despite this quantitative difference, in all other respects the older observers performed similarly to the younger observers. Both age groups were similarly affected by changes in the magnitude of binocular disparity, by reductions in binocular correspondence, and by increases in the speed of stereoscopic motion. In addition, observers in both age groups exhibited an advantage in performance for dynamic stereograms when the patterns of binocular disparity contained significant amounts of correspondence "noise." The process of aging does affect stereopsis, but the effects are quantitative rather than qualitative.     

Age differences in fluid intelligence: contributions of general slowing and frontal decline

The current study examined the contributions of general slowing and frontal decline to age differences in fluid intelligence. Participants aged 20-89 years completed Block Design, Matrix Reasoning, simple reaction time, choice reaction time, Wisconsin Card Sorting, and Tower of London tasks. Age-related declines in fluid intelligence, speed of processing, and frontal function were observed. Hierarchical regression analyses showed that the processing speed and frontal function measures accounted for significant variance in fluid intelligence performance, but there was also a residual effect of age after controlling for each variable individually as well as both variables. An additional analysis showed that the variance in fluid intelligence that was attributable to processing speed was not fully shared with the variance attributable to frontal function. These findings suggest that the age-related decline in fluid intelligence is due to general slowing and frontal decline, as well as other unidentified factors.     

Specific phonological impairments in dyslexia revealed by eyetracking

Phonological deficits in dyslexia are typically assessed using metalinguistic tasks vulnerable to extraneous factors such as attention and memory. The present work takes the novel approach of measuring phonology using eyetracking. Eye movements of dyslexic children were monitored during an auditory word recognition task in which target items in a display (e.g., candle) were accompanied by distractors sharing a cohort (candy) or rhyme (sandal). Like controls, dyslexics showed slower recognition times when a cohort distractor was present than in a baseline condition with only phonologically unrelated distractors. However, unlike controls, dyslexic children did not show slowed recognition of targets with a rhyme distractor, suggesting they had not encoded rhyme relationships. This was further explored in an overt phonological awareness test of cohort and rhyme. Surprisingly, dyslexics showed normal rhyme performance but poorer judgment of initial sounds on these overt tests. The results implicate impaired knowledge of rhyme information in dyslexia; however they also indicate that testing methodology plays a critical role in how such problems are identified.     

Group treatment for trichotillomania: behavior therapy versus supportive therapy

In this randomized controlled trial, group behavior therapy (BT; n = 12) was compared to group supportive therapy (ST; n = 12) in the treatment of trichotillomania (TTM). Both treatments were also compared to a naturally occurring waiting period, the time period that participants waited for groups to form. Participants completing group BT experienced significantly greater decreases in self-reported hair-pulling symptoms and clinician-rated hair loss severity than did those in group ST. Decreases were significantly greater after treatment than after the naturalistic waiting period. In addition, a significantly higher percentage of those in the BT than ST condition were rated as much improved or very much improved on the Clinical Global Impression scale at posttreatment. However, despite substantial symptom improvement, TTM severity remained problematic at posttreatment. Specifically, few participants in either treatment met criteria for clinically significant change at posttreatment. In addition, relapse of symptoms occurred over the 6-month follow-up period. Results provided partial support for the short-term efficacy of group BT. However, the group format may not maximize the efficacy of BT for TTM. Thus, it is recommended that future BT research test either individual therapy or a combination of group and individual formats for TTM.     

When mechanistic models explain

Not all models are explanatory. Some models are data summaries. Some models sketch explanations but leave crucial details unspecified or hidden behind filler terms. Some models are used to conjecture a how-possibly explanation without regard to whether it is a how-actually explanation. I use the Hodgkin and Huxley model of the action potential to illustrate these ways that models can be useful without explaining. I then use the subsequent development of the explanation of the action potential to show what is required of an adequate mechanistic model. Mechanistic models are explanatory.