Analysis of hippocampal atrophy in alcoholic patients by a Kohonen feature map.

We investigated the correlation of hippocampal volume with homocysteine, folate, vitamin B12 and B6 in alcoholic patients and healthy controls applying a Kohonen feature map (KFM) and conventional statistics. Representation of subjects on the KFM suggested an inverse correlation of hippocampal volume with blood levels of homocysteine and correlation with folate and vitamin B6. In conventional statistical analyses (t-test) reduced folate and increased homocysteine was found in alcoholics compared to healthy controls (p < 0.01). In female alcoholics vitamin B6 was reduced significantly (p = 0.03). Multiple linear regression analyses showed a significant correlation between average hippocampal volume and homocysteine (p < 0.001). KFM proved to be a sensitive tool for visualisation of statistical correlations in data sets even if no further statistical information is available.