It includes the reflexive blinking that occurs specifically in response to the rapid approach of an object.
[1][3] The presence or absence of the menace response, in combination with other reflexes, indicates a locus of damage.
Polioencephalomacia damages the visual cortex, impairing the menace response, but leaves the optic nerve, oculomotor nucleus, and oculomotor nerve intact, leaving the pupillary light reflex unaffected.
[1][3] The neural pathway of the menace response comprises the optic (II) and facial (VII) nerves.
It is mediated by tectobulbar fibres in the rostral colliculi of the midbrain passing from the optic tract to accessory nuclei, and thence to the spinal cord and lower motor neurones that innervate the head, neck, and body muscles affected by the response.