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suddenly 1-2 days before menstruation. A minor but steady acceleration of the apeak-frequency during the luteal phase was also noted. The only cyclical changes of the a-rhythm in women under 0. C’s were a slight acceleration 1-2 days prior to menstruation; this is the period following discontinuation of the oral contraceptive.
Variations of performance in psychological tests during the menstrual cycle in women with and without oral contraceptives D. BECKER, P. M. ARNOLD, 0. D. CREUTZFELDT, S. LANGENSTEIN AND W. WUTTKE Institute of Psychology and Max-Planck-Institute for Biophysical Chemistry, Gottingen (G.F.R.) The same 32 young women as in the EEG study were tested for variations in automatized psychological performance tests (EPS 73). These tests covered different performances such as reaction time, concentration, integration and learning abilities. The group with spontaneous menstrual cycles performed significantly better in both speed and accuracy of all tests compared to the group under combined oral contraceptives (0.C’s). During spontaneous menstrual cycles, significantly better performances were achieved during the luteal phase compared to the follicular phase. Best scores in both speed and accuracy of reaction were obtained 1-2 days prior to menstruation; thus, the ability to react fast and accurately correlated with serum progesterone levels and was also linked to the acceleration of the a-rhythm in the EEG. More complex performances such as integrating and learning ability also showed cyclical changes, whereas none of the parameters tested in women under 0.C’s showed any such fluctuations.
Neural and humoral interactions between basal prechiasmatic area and median eminence
Y. SAKUMA AND M. KAWAKAMI - Department of Physiology, Yokohama City University School of Medicine, Yokohama (Japan)
In the Wistar female rat during proestrus, two types of neuronal responses were recorded in the basal prechiasmatic area (PVA), a part of organum vasculosum laminae terminalis, following electrical stimulation of the arcuate nucleus (ARC)median eminence (ME) region, namely, antidromic and orthodromic responses. In the antidromically activated units, high frequency stimuli inhibited somadendritic spikes and subsequent spontaneous activity, Orthodromically activated units were facilitated by the stimulation. Microiontophoresis of LH-RH, LH, FSH, TRH and prolactin was performed on both units. LH-RH and FSH elicited inhibition in about 15% of antidromically activated units respectively, whereas LH excited about 20%. TRH and prolactin
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suddenly 1-2 days before menstruation. A minor but steady acceleration of the apeak-frequency during the luteal phase was also noted. The only cyclical changes of the a-rhythm in women under 0. C’s were a slight acceleration 1-2 days prior to menstruation; this is the period following discontinuation of the oral contraceptive.
Variations of performance in psychological tests during the menstrual cycle in women with and without oral contraceptives D. BECKER, P. M. ARNOLD, 0. D. CREUTZFELDT, S. LANGENSTEIN AND W. WUTTKE Institute of Psychology and Max-Planck-Institute for Biophysical Chemistry, Gottingen (G.F.R.) The same 32 young women as in the EEG study were tested for variations in automatized psychological performance tests (EPS 73). These tests covered different performances such as reaction time, concentration, integration and learning abilities. The group with spontaneous menstrual cycles performed significantly better in both speed and accuracy of all tests compared to the group under combined oral contraceptives (0.C’s). During spontaneous menstrual cycles, significantly better performances were achieved during the luteal phase compared to the follicular phase. Best scores in both speed and accuracy of reaction were obtained 1-2 days prior to menstruation; thus, the ability to react fast and accurately correlated with serum progesterone levels and was also linked to the acceleration of the a-rhythm in the EEG. More complex performances such as integrating and learning ability also showed cyclical changes, whereas none of the parameters tested in women under 0.C’s showed any such fluctuations.
Neural and humoral interactions between basal prechiasmatic area and median eminence
Y. SAKUMA AND M. KAWAKAMI - Department of Physiology, Yokohama City University School of Medicine, Yokohama (Japan)
In the Wistar female rat during proestrus, two types of neuronal responses were recorded in the basal prechiasmatic area (PVA), a part of organum vasculosum laminae terminalis, following electrical stimulation of the arcuate nucleus (ARC)median eminence (ME) region, namely, antidromic and orthodromic responses. In the antidromically activated units, high frequency stimuli inhibited somadendritic spikes and subsequent spontaneous activity, Orthodromically activated units were facilitated by the stimulation. Microiontophoresis of LH-RH, LH, FSH, TRH and prolactin was performed on both units. LH-RH and FSH elicited inhibition in about 15% of antidromically activated units respectively, whereas LH excited about 20%. TRH and prolactin
