Units

Research Unit in Cognitive Neurosciences

UNESCOG investigates the organisation and functioning of the language and cognitive system while taking its biological substrate into account.Experimental psychologists, neuropsychologists and electrophysiologists work on both normal and brain-damaged individuals in the following domains: audio-visual interactions, auditory and visual attention, speech perception and recognition, reading disturbances, cognitive consequences of schooling, literacy and ageing, organisation of the semantic system, retrieval of information from memory (in particular episodic and prospective), re-education of working memory, impairments of executive functions and of social representations due to brain lesion. Besides experimental approaches from cognitive psychology and neuropsyclology, UNESCOG's researchers employ methods of neuropsychological patient examination and of cerebral imagery (recording of evoked potentials and of hemodynamic changes).

Projetcs

Behavioral and electrophysiological study of the phonological and natural categorical boudaries using a VOT (voice onset time) continuum.

The aim of this project is to study the potential residual sensitivity of French speakers to natural, but not phonological, VOT contrasts. For this purpose, we use behavioral methods (identification and discrimination of syllables from a VOT continuum) as well as electrophysiological methods (recording of the MMN).

Speech perception in congenitally profound deaf children

Behavioral and electrophysiological investigation of the processes and neural substrates underlying audiovisual speech perception in congenitally profound deaf children benifiting from a cochlear implant. We will particularly examine the effect of early vs late implantation as well as the effect of the utilisation of Cued Speech on the quality of phonological representations underlying speech learning.

Electrophysiological study of the mechanisms underlying the auditory discrimination of duration contrasts

This research is designed to examine the accuracy with which a change in the moment of detection of a duration deviance is reflected in the Mismatch Negativity (MMN) peak latency. MMNs were recorded using the oddball paradigm on healthy adults. Different standard stimulus durations are used and deviants are 50% shorter or longer. Beside the temporal resolution of the MMN latency as a function of the theoretical moment of deviance direction, standard duration as well as deviance directions effects on MMN amplitude and latency are also examined.

Psycholinguistic units involved in speech recognition

Investigation of the prelexical units involved in the recognition of speech in French, which is compared to other languages. The paradigms used are the phonological priming and the induction of perceptual errors. One examines also the possible influence of orthographic representations on speech attentional strategies and on speech conscious analysis.

Investigation of phonological discrimination evolution in 4 and 8 months old babies by heart rate recordings

Before six months, chidren are able to discriminate all phonemes of all languages. However, from six months, children select only the sounds that are pertinent for their native language. In order to objectively examine this change, we study, thanks to heart rate recordings, phonemic discrimination abilities of 4 and 8 months-old babies presented with syllables from a VOT (Voice Onset Time) continuum.

Audiovisual interaction in the analysis of the spatial scene and in speech.

Behavioral and electrophysiological studies are carried out to specify the constraints and the neural basis of the audiovisual interactions involved both in spatial scene analysis (ventriloquism effect : interaction between visual and auditory data coming from different spatial sources) and in speech perception (McGurk effect : conflict between auditory speech and lipreading).