Objective Measurement and Biological Basis of Anxiety Assessed by Frontal Midline Theta Activity (Fm<theta>)

点击翻译按钮获取中文摘要

The distinct theta rhythm in the frontal midline area during performance of mental tasks has been called Fm<theta>. It is well known that the relief from anxiety might be involved in the appearance of Fm<theta>. In the present study, the objective measurement and the biological basis of anxiety were investigated by using Fm<theta> as an index.The plasma catecholamine responses to mental stress were studied using male students with (n=12) and without (n=12) Fm<theta>. The contents of plasma catecholamines, the appearance time of Fm<theta> and the anxiety scores of two groups were examined during the rest, and before, during and after the calculation. The concentrations of catecholamines in the Fm<theta> appearance group showed lower levels at all times compared to those in the non appearance group. The relief from anxiety in the non appearance group was characterized by a decrease of NA turnover while a decrease of anxiety in the Fm<theta> appearance group involved an increase of DA tur … More nover.The subjects in the Fm<theta> appearance group (n=9) and in the non appearance group (n=9) were given bromocriptine 2.5 mg, sulpiride 50 mg and placebo in a double-blind, crossover design. The appearance of Fm<theta>, the scores of anxiety and the plasma catecholamines were measured before and 1 hr after the drug administration. The similar experiment using clonidine 0.15 mg, yohimbine 5 mg and placebo was also performed. Both an increase of Fm<theta> and a decrease of anxiety in the Fm<theta> appearance group were shown by the stimulation of DA activity, while those in the non appearance group were indicated by the inhibition od DA or NA activity.Twenty eight neurotics and 35 schizophrenics were examined the appearance of Fm<Theta> and the clinical evaluation of symptoms once weekly until Fm<theta> appeared in 2 consecutive weeks, and the plasma catecholamines were also measured before and after the study. A large number of neurotics showed the appearance of Fm<theta> and the inhibition of NA activity according to the improvement of their symptoms. Schizophrenics were divided into two groups, i.e., the Fm<theta> appearance group and the non appearance group. The patients with Fm<theta> responded to the neuroleptics treatment and indicated a decrease of positive symptoms. Less