English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Magnetoencephalographic responses to illusory figures: early evoked gamma is affected by processing of stimulus features

Herrmann, C. S., & Mecklinger, A. (2000). Magnetoencephalographic responses to illusory figures: early evoked gamma is affected by processing of stimulus features. International Journal of Psychophysiology, 38(3), 265-281. doi:10.1016/S0167-8760(00)00170-7.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/11858/00-001M-0000-0010-C4F5-3 Version Permalink: http://hdl.handle.net/11858/00-001M-0000-002C-29D0-A
Genre: Journal Article

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Herrmann, Christoph S.1, Author              
Mecklinger, Axel1, Author              
Affiliations:
1MPI of Cognitive Neuroscience (Leipzig, -2003), The Prior Institutes, MPI for Human Cognitive and Brain Sciences, Max Planck Society, ou_634574              

Content

show
hide
Free keywords: Attention; Binding; Gamma activity; Illusory contours; Kanizsa figures; Magnetoencephalography; MEG; Wavelet transform
 Abstract: We examined evoked and induced responses in event-related fields and gamma activity in the magnetoencephalogram (MEG) during a visual classification task. The objective was to investigate the effects of target classification and the different levels of discrimination between certain stimulus features. We performed two experiments, which differed only in the subjects’ task while the stimuli were identical. In Experiment 1, subjects responded by a button-press to rare Kanizsa squares (targets) among Kanizsa triangles and non-Kanizsa figures (standards). This task requires the processing of both stimulus features (collinearity and number of inducer disks). In Experiment 2, the four stimuli of Experiment 1 were used as standards and the occurrence of an additional stimulus without any feature overlap with the Kanizsa stimuli (a rare and highly salient red fixation cross) had to be detected. Discrimination of collinearity and number of inducer disks was not necessarily required for task performance. We applied a wavelet-based time-frequency analysis to the data and calculated topographical maps of the 40 Hz activity. The early evoked gamma activity (100–200 ms) in Experiment 1 was higher for targets as compared to standards. In Experiment 2, no significant differences were found in the gamma responses to the Kanizsa figures and non-Kanizsa figures. This pattern of results suggests that early evoked gamma activity in response to visual stimuli is affected by the targetness of a stimulus and the need to discriminate between the features of a stimulus.

Details

show
hide
Language(s): eng - English
 Dates: 2000
 Publication Status: Published in print
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: -
 Identifiers: eDoc: 239651
ISI: 000165915000007
Other: P7036
DOI: 10.1016/S0167-8760(00)00170-7
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: International Journal of Psychophysiology
  Other : Int. J. Psychophysiol.
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Amsterdam : Elsevier
Pages: - Volume / Issue: 38 (3) Sequence Number: - Start / End Page: 265 - 281 Identifier: ISSN: 0167-8760
CoNE: https://pure.mpg.de/cone/journals/resource/954925484686