How many impressions can our brain hold in mind at any moment? How long lasts one moment? And do we see and think in a continuous flow or in discrete steps? The research project “Seeing Objects in Rhythms” funded through a Lise-Meitner fellowship by the Austrian Science Fund FWF aims to shed light on these fundamental enigmas of human information processing.
My core hypothesis: Objects are not continuously tracked but rhythmically sampled, and capacity limits root in the speed of the sampling rhythm.
Starting from a theoretical model for multiple-object processing based on discrete, periodic sampling cycles, my research project uses high-temporal resolution neuro-imaging techniques (i.e. magnetoencephalography, MEG) to capture and neuro-stimulation methods to shape the rhythmic impact of brain processes on object capacity. Classically, object capacity is thought of a mental limit to the amount of processed information in our spatial (3-D) surrounding. But things around us move and change over time, and so do our mental and neural processes (in 4-D). My research links rhythmic fluctuations in attention over time to object memory and identifies a temporal architecture for cognition in neural oscillation pattens.
(b) Object capacity increases in steps within 100 ms (time slices generated with forward masking)
(c) MEG substrates in oscillatory phase coherence in the alpha band over parieto-occipital cortex
Figures adapted from
Wutz and Melcher, Frontiers in Psychology, 2014
Wutz et al., J Neurosci, 2014
(d) Theta and alpha oscillations impact the processing episode.
(e) Beta and gamma oscillations impact the processed objects.