A gated electronic switch for stimulation and recording with a single electrode
A circuit design is described for an electronic device which is gate controlled to rapidly switch electrode connections between a stimulator and an amplifier. An integrated switch in the circuit is operated by transistor-transistor logic pulses and will conduct analog signals of up to 15 V amplitude. Electrographic records made using the switch show multi-unit spike discharge after repetitive stimulation of the amygdala in the kindled rat.
Cyclic nucleotides in the amygdala of the kindled rat
The basolateral amygdala of rats was stimulated once daily until three successive fully kindled seizures were elicited. Twenty-four hours after the last seizure the rats were sacrificed by focused microwave irradiation to the head. Tissues from homolateral and contralateral amygdala and cerebral cortex were assayed for cAMP and cGMP content. No significant changes in cyclic nucleotides were measured in the kindled animals. These studies indicate that long term changes in the steady-state level of total tissue cyclic nucleotides do not occur concomitant with the persistently altered excitability associated with kindling of the amygdala.
Time lapse photography of clouds from high altitude balloons.
Time lapse pictures of clouds taken by cameras flown at altitudes of 30 km on balloons provide valuable insights into the convection and electrification of cloud systems. Simple camera arrangements for taking such pictures are described.