In clinical practice, electroencephalography (EEG) can remind us that the human executive function is based on neural activity and its oscillation. It is generally considered that each neuron receives electrical inputs from other neurons and produces an action potential to transmit signals to the next neuron, leading to the generation of a neural network underlying mental activity. However, these mechanisms remain poorly understood. Thus, it is necessary to accumulate new knowledge about neuronal activity to overcome mental disease in the future. In the cerebral cortex or hippocampus, the core regions of the executive function, neurons are mainly classified into two types, pyramidal cells and interneurons, which are excitatory glutamatergic neurons and inhibitory GABAergic neurons. Whole-cell patch clamp recording is widely known as a laboratory technique in electrophysiology. This technique enables us to record one neuron's electrical activity, such as action potentials, excitatory synaptic inputs, and inhibitory synaptic inputs. In this review, I would like to introduce several studies conducted using this technique to further our understanding of the pathophysiology of psychiatric illness.
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