Flash P2 delay in primary degenerative dementia of the Alzheimer type.

ABSTRACT

1. Flash visual evoked responses of 31 patients meeting DSM-III-R criteria for primary degenerative dementia of the Alzheimer type were compared with 31 healthy controls. 2. P1 latency was normal (75 +/- 6 msec Alzheimer's; 75 +/- 6 msec controls). 3. P2 was significantly delayed (162 +/- 32 msec, 147 +/- 20 msec, p < 0.03) among patients. 4. P1-P2 interpeak latency was significantly increased (87 +/- 32 msec, 71 +/- 21 msec, p < 0.03) among patients.