Postnatal development of the electrocortical activity in the golden hamster (Mesocricetus auratus)

Abstract Electrical activity was recorded from the occipital and parietal cortices of the golden hamster at the ages of 1, 2, 5, 7, 10, 13, 15, 20, 25, 30, 45, days, and adult (1 yr). Additional animlas were used for determination of brain weight and for studies of neuronal development. In the golden hamster the ECoG activity appeared by Postnatal Day 2 as intermittent and slightly irregular low voltage activity. From 7 to 10 days the amount of fast activity (18 ‐ 20 cps) increased as did the amplitude in the slow waves of 6 – 9 cps. By 15 days the ECoG pattern was essentially similar to that the adult hamster. However, an augmentation in voltage and a predominance of faster rhythms (18 ‐ 25 cps) were observed as the animal matured. Neurohistological data revealed that the cortex approached the general anatomical pattern of the adult by the 13th to 15th postnatal day.