Title
Visual gamma oscillations and evoked responses: Variability, repeatability and structural MRI correlates
Abstract
There is increasing interest in the role gamma oscillations (∼40 Hz) play in visual information processing. Despite this interest, and in contrast to the classically studied visual evoked potential, surprisingly little is known about the intra-individual repeatability of induced gamma oscillations. Similarly, little is known about inter-individual variability in terms of gamma oscillation frequency, bandwidth and amplitude with no extant normative data for these parameters. The purpose of the current study was therefore to examine the repeatability of visual gamma oscillations and to provide the first normative data on them. Our results demonstrate that evoked responses were highly repeatable across recording sessions whereas for induced visual gamma oscillations a large amount of inter-individual variability existed in terms of frequency, bandwidth and amplitude. However, these parameters and the general morphology of the gamma band response were stable within the same individuals for at least 4 weeks. The high degree of individual variability in gamma oscillations for gamma amplitude, bandwidth and frequency suggests that between-group studies on gamma oscillations will be difficult, requiring relatively large amounts of data to detect differences. However, the high degree of individual repeatability for gamma oscillation frequency, bandwidth and amplitude suggests that these dependent variables will be well suited for repeated-measure designs such as pharmacological studies. A number of individuals are described which show clear evoked responses yet a near absence of gamma oscillations and vice versa suggesting dissociations between the generative mechanisms of these responses. Our results also demonstrate that gamma frequency tends to decline with age and is positively correlated with the thickness of the pericalcarine cortex.
Year
DOI
Venue
2010
10.1016/j.neuroimage.2009.11.045
NeuroImage
Field
DocType
Volume
Developmental psychology,Oscillation,GENERAL MORPHOLOGY,Psychology,Bandwidth (signal processing),Evoked potential,Gamma band,Extant taxon,Amplitude,Repeatability
Journal
49
Issue
ISSN
Citations 
4
1053-8119
31
PageRank 
References 
Authors
1.71
11
4
Name
Order
Citations
PageRank
Suresh D. Muthukumaraswamy112010.62
Krish D. Singh229434.20
Jennifer B. Swettenham3422.64
Derek K. Jones465548.55