The oscillatory dynamics of recognition memory and its relationship to event-related responses.
The large-scale neural dynamics underlying higher cognitive processes are characterized by at least three types of stimulus-response: (i) the resetting of ongoing oscillatory brain activity without concomitant changes in response amplitude (phase alignment response); (ii) the addition of response amplitude to the ongoing brain activity in a time-locked manner (evoked response); and (iii) the addition of response amplitude that is not time-locked (induced response). Recent animal studies identified evoked responses as a characteristic neural response during stimulus perception but leave open the possibility that higher cognition, such as memory, is characterized more predominantly by phase alignment and/or induced responses. Using whole-head single-trial magnetoencephalography data from eight healthy adults, we show that all three types of response are related to the discrimination of old and new stimuli in a visual word recognition memory paradigm. In four subjects, single-trial evoked responses were the single constituents of event-related field old/new differences that have been previously related to familiarity-based and recollection-based recognition memory. While these data show that the oscillatory brain dynamics underlying recognition memory are characterized by a complex mix of three types of stimulus-response, they also clearly implicate evoked responses in higher cognitive processes such as recognition memory.
Düzel
Emrah
E
Department of Neurology II, Otto von Guericke University, Leipziger Strasse 44, 39120 Magdeburg, Germany. emrah.duezel@medizin.uni-magdeburg.de
Neufang
Markus
M
Heinze
Hans-Jochen
HJ
D000328:Adult; D003071:Cognition / Q000502:physiology; D004192:Discrimination, Psychological / Q000502:physiology; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D010296:Parietal Lobe / Q000502:physiology; D010507:Periodicity; D021641:Recognition, Psychology / Q000502:physiology*; D013702:Temporal Lobe / Q000502:physiology; D014796:Visual Perception / Q000502:physiology