The term 'transmitter impulse' refers to the electrical signals that are sent from a neuron's axon. The axon is a long, thin fiber that extends from the cell body of a neuron and is responsible for transmitting electrical signals to other cells. The axon is also known as an 'axon terminal' or 'axon hillock'. The transmitter impulse is the electrical signal that is sent from the axon to other cells, allowing them to communicate with each other.