Clin Surg | Volume 6, Issue 1 | Research Article | Open Access

Properties Extracellular Action Potentials from Posteromedial Hypothalamus

Jesús Pastor1,2,*, Lorena Vega-Zelaya1,2 and Elena Martín Abad1,2

1Clinical Neurophysiology, Hospital Universitario La Princesa, Diego de León, Spain
2Foundation for Biomedical Research, Diego de León, Spain

*Correspondance to: Jesús Pastor 

Fulltext PDF


We have described the electrophysiological properties of the Extracellular Action Potential (EAP) picked up through Microelectrode-Recordings (MERs) from four patients operated under general anaesthesia at Postero-Medial Hypothalamus (PMH) by Deep Brain Stimulation (DBS) for erethism. EAPs from the same cell were pooled to obtain a mean EAP (mAP). The amplitudes and durations for all 2/3 phases were computed from the mAP, together with the maximum (dVmax) and minimum (dVmin) values of the first derivative. mAPs are denominated according to the phase polarity (P/N for positive/negative). We obtained a total 159 mAPs, all of them positive and a clear majority triphasic (89.9%) with a small P/N deflection (V1) before depolarization. The percentage of the different types of mAPs was surprisingly similar to that described recently at thalamus and although were some properties as peak-to-peak amplitude or overall duration. We observed a high correlation between absolute amplitude of the first phase (V1) and the amplitudes of either depolarization (V2) or repolarization (V3) phases, meaning that a causal relationship between them probably exists. We postulate capacitive current as responsible for V1, although it’s difficult to explain the appearing of the same polarity for the capacitive voltage and for the voltage induced by transmembrane ionic current.


Agglomerative method; Aggressiveness; Capacitive current; Deep brain stimulation; erethism; Microelectrode recordings; Sorting spikes


Pastor J, Vega-Zelaya L, Martín Abad E. Properties Extracellular Action Potentials from Posteromedial Hypothalamus. Clin Surg. 2021; 6: 3224..

Subscribe to Our Newsletter