Abnormal flash visual evoked response in melancholia: a replication study.
Grand mean flash visual evoked responses (FVER) were measured in two new groups of depressed patients with melancholia to replicate findings of an abnormal FVER in a previously reported pilot study (Vasile et al 1989). These different, independently collected groups of melancholic patients demonstrated a statistically significant negative deviation of the FVER 224-300 msec poststimulus maximal in the midline centroparietal region when compared with appropriate normative age-matched control groups (n = 56) in each group). We utilized the identical computer-based quantified neurophysiological technique with mapping to analyze the data in all three melancholic patient groups--the pilot group (n = 9) with mean age 73.1 years, an older replication group (n = 14) with mean age 75.5 years, and a younger replication group (n = 15) with mean age 63.8 years. We also studied a group of depressed patients without melancholia (n = 11) with mean age 65.2 years, and found a similar, but less pronounced, alteration of the FVER. Lastly, we studied a group of nondepressed neuropsychiatric patients (n = 10) with mean age 61.9 years and found no abnormality of the FVER. Our data suggest that a gradient of FVER abnormality exists in depressed patients, most prominent, but not limited to elderly melancholic patients.