Allocentric spatial memory activation of the hippocampal formation measured with fMRI.
Hippocampal activation was investigated, comparing allocentric and egocentric spatial memory. Healthy participants were immersed in a virtual reality circular arena, with pattern-rendered walls. In a viewpoint-independent task, they moved toward a pole, which was then removed. They were relocated to another position and had to move to the prior location of the pole. For viewpoint-dependent memory, the participants were not moved to a new starting point, but the patterns were rotated to prevent them from indicating the final position. Hippocampal and parahippocampal activation were found in the viewpoint-independent memory encoding phase. Viewpoint-dependent memory did not result in such activation. These results suggest differential activation of the hippocampal formation during allocentric encoding, in partial support of the spatial mapping hypothesis as applied to humans.
Parslow
David M
DM
King's College London, London, United Kingdom. d.parslow@iop.kcl.ac.uk
Rose
David
D
Brooks
Barbara
B
Fleminger
Simon
S
Gray
Jeffrey A
JA
Giampietro
Vincent
V
Brammer
Michael J
MJ
Williams
Steven
S
Gasston
David
D
Andrew
Christopher
C
Vythelingum
Goparlen N
GN
Loannou
Glafkos
G
Simmons
Andrew
A
Morris
Robin G
RG
D000328:Adult; D001931:Brain Mapping; D002531:Cerebellum / Q000502:physiology; D002540:Cerebral Cortex / Q000502:physiology*; D003463:Cues; D004292:Dominance, Cerebral / Q000502:physiology; D006624:Hippocampus / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D011939:Mental Recall / Q000502:physiology; D008875:Middle Aged; D009415:Nerve Net / Q000502:physiology; D009949:Orientation / Q000502:physiology*; D020534:Parahippocampal Gyrus / Q000502:physiology; D010364:Pattern Recognition, Visual / Q000502:physiology; D012016:Reference Values; D012153:Retention, Psychology / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D013788:Thalamus / Q000502:physiology; D014584:User-Computer Interface