Event-related potentials study

Jose Herrero, University of Newcastle, UK
Andrey Nikolaev, RIKEN BSI, Japan
Antonino Raffone, Sapienza University of Rome, Italy
Cees van Leeuwen, RIKEN BSI, Japan

Visual working memory has a limited storage capacity. Therefore efficient selection of objects for storage is crucial. We study perceptual and post-perceptual selection of multiple targets for storage in visual working memory. Our experiment consists of three steps. First, we present to our participants an array of spatial cues which inform them about the following target locations. Then, we present the array of targets (memory array) for 1 min (see below) and ask participants to remember it.

Finally, we present a test array and participants have to response whether the color of a target in a certain location is different from that in the memory array. At the same time we record event-related potentials (ERP). We analyze early ERP components which reflect perceptual selection for storage. We also study the long-lasting component during memorization stage (memory wave) which is related to consolidation and maintenance in visual working memory. We observed that only the first part of the memory wave associated with consolidation was affected by spatial cues. The second, related to maintenance, part was not changed by spatial cues presentation. Our results, therefore, show that attentional selection is important for consolidation.

Reference 

J. Herrero, A.R. Nikolaev, A. Raffone, C. van Leeuwen. Selective attention in visual short-term memory consolidation. Neuroreport. 2009, 20(7): 652-656.