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).
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.
Adapting the environment, an alternative way of managing children with ADHD: the clinical, neuropsychological and neurophysiological evaluation of a new paradigm
The main objective of my PhD is to explore and evaluate, at a behavioral and electrophysiological (with event-related potentials and EEG) level, the benefits of a 'stimulating' environment in ADHD children from both subtypes (inattentive type and combined type), compared to the benefits of medication.With the use of a visual cued Go/Nogo, executive functions and attention are evaluated in ADHD and healthy matched children. The children perform the task listening (or not) to a white noise (stimulating environment). The ADHD children usually under methylphenidate will take the test twice, so that their performance can be compared.
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.
Behavioural and brain cartography (IRMf, MEG, ERPs) studies of the effects of auditory training on the categorical perception of voice onset time (VOT)
The aim of this study is to differentiate phonological and acoustical training effects on the categorical perception of voice onset time (VOT). This methodology is particularly relevant in French because the different representation levels of speech stimuli may be easily dissociated. Preliminary studies exhibited behavioural and electrophysiological modifications following a training focused on the negative side of a VOT continuum. The behavioural part of this study will attempt to determine the most efficient training procedures. We will also try to determine and differentiate, using ERPs and fMRI or MEG, the neural systems involved in the different representation levels of speech and the training effects on such neural systems. Finally, we will integrate all our data in a clinical part in order to analyse and improve the categorical perception of children with specific language impairment (SLI).
Multi-signal integration and French cued speech perception
Speech perception in hearingsubjects has been shown to involve audio-visual integration. French Cued Speech, or Langue françaiseParléeComplétée (LPC), is a system of manual aids developed to help deaf people to clearly and completely understand speech visually, thereby compensating for lipreading ambiguity. Since this system is also multi-signal (sound, lip movements and LPC gestures), we were wondered whether this perception involves integrative treatment and how expertise affects it.French Cued Speech perception is a recent study field. Currently no research has used electroencephalography and eye tracking techniques. Our research is the first which combine electroencephalography and eye tracking with behavioural data. Totally painless, these techniques record on line brain electric activity and eye movement.