Laboratoire Psychologie de la Perception Institut Neurosciences Cognition Université Paris Descartes Centre National de Recherche Scientifique
Home
Research
vision Vision
action Action
speech Speech
avoc AVoC
support support staff
People
Former Staff
Teaching
Publications
Ethics
Events
Practical

Calendar
Opportunities
Internships
Contracts
Platforms
Links

Baby Lab

Intranet
Processing temporal events simultaneously in healthy human adults and in hemi-neglect patients

Many theories have been advanced to explain how the brain incorporates time into its computations, in particular for the purpose of estimating the duration of an event. In the present study we examine with a new paradigm the ability to compare the duration of two visual stimuli in the parafoveal visual field, presented either sequentially or overlapping in time. We found that judging the duration of a pair of objects is more difficult when they overlap in time. Furthermore, all healthy participants presented a bias to over-estimate the duration of the second event (a negative time-order-error). We then presented the same task to eight left neglect patients with extinction (N-patients). Relative to the healthy participants, the patients displayed similar loss of sensitivity and increased bias in the time overlap condition. However, N-patients were particularly impaired when the first object was presented in their right visual field and the second one appeared on their left before the first one vanished. Rather than a simple engage/disengage disorder, these results highlight a specific problem with shifting attention to the impaired visual field. We discuss these findings in the light of contemporary models of time estimation.



PDF Link