Psychiatry research
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Psychiatry research · Apr 2010
Effects of antidepressant treatment on N-acetyl aspartate and choline levels in the hippocampus and thalami of post-stroke depression patients: a study using (1)H magnetic resonance spectroscopy.
Previous studies in patients with a major depressive disorder show functional abnormalities in the medial frontal cortex. Functional and structural abnormalities in patients with post-stroke depression (PSD) are not well studied. The major goals of this study were to determine the biochemical abnormalities that occur in PSD and to assess the effect of antidepressants in patients with PSD at the biochemical level. ⋯ They had significantly lower Cho/Cr ratios in bilateral hippocampus and left thalamus. Our study suggests that metabolic abnormalities in the hippocampus and thalamus are implicated in PSD. Antidepressants may alter the local metabolic abnormalities in these areas.
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Psychiatry research · Apr 2010
Event-related potential based evidence of cognitive dysfunction in patients during the first episode of depression using a novelty oddball task.
Studies using event-related potentials (ERP) to investigate cognitive dysfunction associated with depression have generated variable findings. The differences among reported results are typically attributed to the disparity of the samples. To eliminate the effects of factors such as medication and comorbidity with other psychiatric disorders, first-episode unmedicated patients suffering from depression were recruited in this study. ⋯ For the target tones, depressed subjects showed reduced N2 at anterior regions and reduced target P3 in the right hemisphere. In response to novel stimuli, there was a reduced amplitude of the novelty P3 component at the fronto-central region in depressed patients. Our findings suggest that patients with depression in the initial stages show an impaired ability in voluntary and involuntary attention and exhibit frontal lobe and right-hemisphere dysfunctions.