face processing in frequency domain Flashcards
what does research suggest about gamma oscillations
research into gamma oscillations seems to suggest that signals appear in the same frequency band in distinct areas at distinct times.
binding sychrony hypothesis
the binding synchrony hypothesis suggests that gamma frequencies found in dedicated areas process different aspects of a stimulus
Tallon-Boudry (2009)
whilst signalling they are processing the same stimulus
what does scalp EEG reflect
scalp EEG reflects the synchronisation of neural activity.
a power increase in a given frequency band at an electrode is considered local synchrony, generated through neural interaction
Zion-Golumbic and Bentin (2007)
- used EEG oscillations across the scalp to investigate the differenced in processing faces compared to non-face related stimuli
- compared face related stimuli and watched (that have a face)
- induced oscillatory patterns were found across the scalp in low (25-40Hz) and high (55-70Hz) gamma band oscillations
- it is proposed that this gamma band oscillatory synchrony occurring 100ms after the N170 response is related to the processing of higher level representations of a face (e.g. familiarity) as well as processing among features.
Rodriguez et al (1999)
increased gamma band power was also discovered when looking at upright faces compared to inverted faces
- this suggests that the increase in gamma oscillations is related to face processing
- inferotemporal cortex and frontal areas
perceptual binding
the processing related to multiple features of a face, linked to gamma band oscillations across the brain, is referred to as perceptual binding
increased gamma band activity
100ms after the N170 response is said to be a transition from recognition of a face and processing simple stimuli, to the transition to processing more complex features as a gestalt.
