Biomedical subjects

Mireille Besson

Publications and source records attributed to Mireille Besson.

7 recordsLinked to original sources

PubMed2003

Different brain mechanisms mediate two strategies in arithmetic: evidence from Event-Related brain Potentials.

Participants were asked to verify if complex additions were smaller than 100 or not. Two hundred and forty arithmetic problems were presented, with half the problems being small-split problems (i.e. proposed sums were 2 or 5% away from 100) and half being large-split problems (i.e. proposed sums were 10 or 15% away from 100). Behavioral and ERPs data indicate that participants may use two different strategies to verify complex inequalities, a whole-calculation strategy for small-split problems and an approximate-calculation strategy for large-split problems. The choice between these two strategies occurred within 250 ms post-stimulus presentation, and strategy execution was lateralized. Implications for our understanding of the brain mechanisms underlying arithmetic problem solving are discussed.

Adult↗

PubMed2003

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.

Adult↗

PubMed2002

An fMRI study of music sight-reading.

The brain areas involved in music reading were investigated using fMRI. In order to evaluate the specificity of these areas we compared reading music notation to reading verbal and number notations in a task that required professional pianists to play the notes (in musical and verbal notations) and the numbers displayed on a 5-key keyboard. Overall, the three tasks revealed a similar pattern of activated brain areas. However, direct contrasts between the music notation and the verbal or the numerical notation tasks also revealed specific major foci of activation in the right occipito-temporal junction, superior parietal lobule and the intraparietal sulcus. We interpret the right occipito-temporal difference as due to differences at the encoding level between notes, words and numbers. This area might be analogous to one described for words, called the visual word form area. The parietal activations are discussed in terms of visuo-motor transcoding pathways that differ for the three types of notations used. Finally, we present a model of music reading that can possibly explain our findings.

Auditory Perception↗

PubMed2002

Emotional prosody: sex differences in sensitivity to speech melody.

Emotional prosody is defined as the ability to express emotions through variations of different parameters of the human speech, such as pitch contour, intensity and duration. A recent study has discovered clear differences between men and women in the time course of emotional prosodic processing. There are several interpretations of these intriguing results that hold promise for future studies on language comprehension.

Journal Article↗

PubMed2002

Processing pitch and duration in music reading: a RT-ERP study.

The originality of this study is to examine the processing of pitch and duration in music reading, using both electrophysiological and behavioral methods. Specifically, it was of interest to determine whether pitch and duration in music reading are processed independently or jointly. A probe, comprising a key and time signature was presented, and participants were required to compute the tonic and/or the best fitting duration. A target note followed the probe and participants made a match/mismatch judgment on the dimension they were required to analyze (i.e. pitch or duration). We hypothesized that, if pitch and duration are processed independently results should show no interference of the irrelevant dimension on the relevant. Results showed that early differences emerged in the ERPs as a function of the task to be performed on the target in block 1. Moreover, RTs were shorter in the pitch than in the duration task and for congruous than incongruous targets. In the ERPs, this congruity effect was reflected by a negative component, to incongruous targets. Most importantly, the congruency of the target note on the irrelevant dimension did not have any effect on the ERPs, suggesting that pitch and duration are processed independently.

Adult↗

PubMed2002

An electrophysiological study of dyslexic and control adults in a sentence reading task.

Event-related potentials and cued-recall performance were used to compare dyslexic and control adult subjects. Sentences that ended either congruously or incongruously were presented visually, one word at a time, at fast (stimulus-onset-asynchrony (SOA)=100 ms) or slow (SOA=700 ms) rates of presentation. Results revealed (1) a large effect of presentation rate that started with the N1-P2 components and lasted for the entire recording period, (2) larger N400 components for dyslexic than control subjects, at slow presentation rates, to both congruous and incongruous endings and (3) a large ERPs difference related to memory (Dm effect) that did not differentiate controls from dyslexics but was larger at slow than at fast rates of presentation. These findings indicate that the reading impairment observed in the present group of adult dyslexics is more likely to result from difficulties integrating the meaning of words within a sentence context than from pure sensory processing deficits.

Adult↗

PubMed2002

Separable neuronal circuitries for manipulable and non-manipulable objects in working memory.

Previous work using single-cell recordings in monkeys and neuro-imaging studies in humans has shown that perceiving an object or imaging the action associated with the object recruits the same brain regions in the ventral premotor cortex as performing an action with the object. We used functional magnetic resonance imaging (fMRI) for examining whether similar brain regions are also activated while maintaining information about manipulable objects in working memory. Holding information about manipulable objects in working memory activated the left ventral premotor cortex and the left inferior frontal gyrus (Broca's area). Conversely, non-manipulable objects to be held in working memory co-activated Broca's area and the left angular gyrus. When contrasted directly, manipulable relative to non-manipulable objects activated the left ventral premotor cortex and the anterior intraparietal sulcus, a circuitry that is assumed to mediate the transformation of movement-relevant object properties into hand actions. These results indicate that visual working memory for manipulable objects is based on motor programmes associated with their use. Similar to speech motor programmes in verbal memory tasks, hand motor programmes may allow the maintenance of objects in working memory over short intervals.

Adult↗