OHBA SEMINAR SERIES
Professor Virginie van Wassenhove (INSERM)
Monday, 07 December 2015, 2pm to 3pm
Department of Psychiatry Seminar Room
Hosted by email@example.com
Temporal cognition: Time as content, Time as structure
One goal of time research is to link the dynamics of brain processes (timing) with the conscious experience of time (time experience). Traditionally, the hallmark of time perception is the experience of duration or “time quantity” (Lambrechts et al, 2013) necessitating two temporal markers that are the onset and the offset of an event. Brain responses to temporal markers can be indexed by evoked activity (e.g recorded with electro- and magneto-encephalography; EEG and MEG, respectively). However, this presupposes a latency-code mechanism for the encoding of events in time, which is difficult to reconcile with the inherent temporal delays of cortical information processing (van Wassenhove, 2009). For instance, the temporal coincidence of auditory (A) and visual (V) events is a necessary condition for multisensory integration, yet coincidence is defined by the brain, not by veridical simultaneity; consistent with this, the temporal structure of sensory events is a driving cue for multisensory integration (Zilber et al, 2014). Additionally, the perception of audiovisual (AV) speech can tolerate as much as 250 ms of desynchrony between sensory inputs suggesting the existence of temporal encoding windows (van Wassenhove et al, 2007) and specific temporal regimes for sensory integration (Kösem & van Wassenhove, 2012). An alternative approach thus consists in characterizing neural oscillations which naturally provide such temporal constants (Treisman et al, 1990; Pöppel, 1997, 2009; Buhusi & Meck, 2005; van Wassenhove, 2009). In this view, the dynamics of brain activity provides the logistical platform or chronoarchitecture hypothesized to serve canonical operations for temporal event structuring at all time scales. Distinct neurophysiological markers should thus be found that index the structuring of events in time specifically for time perception and temporal cognition. For instance, we showed that the encoding of event timing capitalizes on the oscillatory processes at an early stage of sensory processing and that the phase of neural oscillations linearly correlates with participants’ perceived simultaneity of auditory and visual events (Kösem et al., 2014). Implications of these results for temporal cognition are discussed in the context of the dissociation between interval and phase sense (Gallistel, 1990).