Abstract
Visual working memory (VWM) allows us to actively represent a limited amount of visual information in mind at a given moment. Recent electrophysiological studies have consistently shown that modulations of the power of parieto-occipital alpha activity (8-13Hz) is directly involved in active maintenance of VWM representations. For example, the reduction of the parieto-occipital alpha power observed during the VWM retention interval shows the capacity-limited set size effect predicted by the behavioral measures of VWM capacity (Erikson, et al., 2016; Fukuda, Mance, & Vogel, 2015; Fukuda, Kang, & Woodman, 2016). Furthermore, the topographical distribution of this alpha power modulation during VWM delay can be used to decode the content of VWM (Foster, et al., 2016; Fukuda, Kang, & Woodman, 2016; Samaha, Sprague, & Postle, 2016). In this study, we sought to extend this finding by specifying the nature of the representation in VWM that are reflected in these parieto-occipital alpha power dynamics. More specifically, we had participants maintain location, color, or their conjunction in a short-term memory task while we recorded their electroencephalograms (EEGs). Pattern classification results revealed that location information, but not color information, can be reliably decoded from the topographical distribution of the parieto-occipital alpha power during the retention interval of the memory task. This finding clearly demonstrates the selective sensitivity of the parieto-occipital alpha activity to the storage of spatial locations in VWM.
Meeting abstract presented at VSS 2017