"What" and "where" in the intraparietal sulcus: an FMRI study of object identity and location in visual short-term memory.
The intraparietal sulcus (IPS) has been closely linked to limitations of visual short-term memory capacity (VSTM; Todd and Marois 2004; Xu and Chun 2006). It is not clearly known, however, to what extent IPS activation reflects VSTM for object identity (What) versus spatial location (Where) information. The present study was designed to manipulate selectively the amount of What and Where information retained in VSTM in order to determine, using functional magnetic resonance imaging, the effect of VSTM for each of these 2 dimensions on IPS activation. The results showed an increase in IPS activation only in response to increasing Where memory load, with no effect of What load suggesting that capacity-related activation in the IPS primarily reflects the amount of spatial information retained in VSTM.
Harrison
Amabilis
A
Department of Psychology, Université de Montréal, Montréal, Québec H2V 2S9, Canada. harriah@mcmaster.ca
Jolicoeur
Pierre
P
Marois
René
R
D000328:Adult; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology; D001931:Brain Mapping; D003118:Color Perception / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D010296:Parietal Lobe / Q000098:blood supply* / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D013997:Time Factors; D055815:Young Adult
D010100:Oxygen