Changes in the motor response threshold to direct electric stimulation of the motor cortex during elaboration of conditioned reflex switching-over

During elaboration of switching-over of an alimentary salivary conditioned reflex to a defensive one in dogs, with foreleg passive flexion as a signal stimulus, excitability changes of opposite signs appeared in the cortical representation of the left foreleg. At the stage of elaborated switching-over, the threshold of the flexor reaction to a direct stimulation of the motor cortex became lower in the alimentary experimental situation (passive rise--milk) and rose in the defensive situation (passive rise--acid).     

Electroretinographic testing in diabetics: a comparison study of the Burian-Allen and the Henkes corneal electrodes

A series of 57 diabetics underwent standard electroretinographic recordings for the purpose of testing the effect of insulin on the electroretinograms in diabetes mellitus, specifically on the oscillatory potential changes (Kozak et al., Jap. J. Ophthal. Suppl., 1979). Use of the speculum-type corneal electrode (Burian-Allen, Hansen Labs.,) produced 9 corneal abrasions in the first 28 patients in this series. However, when the technique of examination was altered by use of the Henkes-type bipolar electrode, only 2 abrasions were produced in the last 29 patients. These frequencies of abrasions are statistically different. The suggestion is made that electroretinographic tracings in diabetics the performed with the use of the Henkes bipolar low-vacuum corneal electrode (Medical Workshops, Holland).