Locally weighted interpolating growing neural gas.

In this paper, we propose a new approach to function approximation based on a growing neural gas (GNG), a self-organizing map (SOM) which is able to adapt to the local dimension of a possible high-dimensional input distribution. Local models are built interpolating between values associated with the map's neurons. These models are combined using a weighted sum to yield the final approximation value.

Potential psychosocial mechanisms linking depression to immune function in elderly subjects.

Although depression and immune changes in elderly subjects constitute a considerable health risk, mechanisms underlying the association between depression and immune function are unclear. The question of whether personality and social support can explain the variation in immune function during depression was addressed in 21 elderly depressive and 23 control subjects. The following variables were studied: neuroticism, extraversion, received social support, depression-related immune parameters [i.

Urinary free cortisol excretion in elderly persons with minor and major depression.

Several studies have found that cortisol hypersecretion may occur in severely depressed patients, characterized by melancholic features. On the other hand, illness chronicity seems to be related to low, rather than high, cortisol levels. This study aims to trace factors associated with 24-h urinary free cortisol levels in a sample of 23 elderly persons with major or minor depression and 21 non-depressed control subjects.

Increase of NK-T cells in aged depressed patients not treated with antidepressive drugs.

Background: A change in number and/or activity of natural killer cells has repeatedly been reported in depressive illness. Much less attention has yet been given to the subgroup of natural killer cells that are positive for the T-cell marker CD3 (NK-T cells). These cells possibly have important immunoregulatory properties.

Lithium treatment in affective disorders: The significance of strongly elevated erythrocyte choline levels.

In manic-depressive patients treated with lithium salts the transport of choline over the erythrocyte membrane is strongly inhibited, resulting in dramatically increased erythrocyte choline levels (for review see ref. 1). Whether or not there is a relationship between this effect and treatment response is not clear.