He used focal ionophoresis and pressure injections to apply glutamate and other agonists including NMDA , AMPA , and kainate to different regions of the neurons .
He noticed that certain hot spots were desensitized more rapidly that other sites on the neuron .
Using focal ionophoresis and pressure injections to apply glutamate and other agonists including NMDA , AMPA , and kainate to different regions of the neurons , he noticed that certain hot spots were desensitized more rapidly that other sites on the neuron .