The role of the right medial temporal lobe in the control of memory-guided saccades.
The role of the hippocampal formation in the control of memory-guided saccades is unclear. We tested two types of memory-guided saccades with short memorization delay in three patients with a lesion affecting the right medial temporal lobe and involving the hippocampal formation. In single memory-guided saccades, testing spatial working memory, the gain of the patient group did not differ from that of an age-matched control group. In contrast, in sequences of memory-guided saccades, testing chronological working memory, there was a marked and significant increase in the percentage of erroneous sequences in patients, compared to controls. These results suggest an important role of the hippocampal formation in the memorization of the chronological order of saccade sequences. In contrast, this structure does not appear to be crucial for spatial working memory, used in single memory-guided saccades.
Laboratoire INSERM 289, Hôpital de la Salpêtrière, Paris, France.
R M
RM
Müri
S
S
Rivaud
S
S
Timsit
P
P
Cornu
C
C
Pierrot-Deseilligny
D000368:Aged; D001927:Brain Diseases / Q000503:physiopathology; D006624:Hippocampus / Q000502:physiology; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D008875:Middle Aged; D012438:Saccades / Q000502:physiology*; D013702:Temporal Lobe / Q000502:physiology*