Lateral Inhibition

by Greg Crowther

One of the nervous system's fundamental tasks is to detect the edges of things -- for example, the edge of a dark-colored object against a light background, or the transition between areas of skin that are and are not being pressed. Sensory cells and sensory neurons that are adjacent to each other may inhibit each other in a way that exaggerates the differences in sensory stimuli at these borders, allowing us to detect the borders more precisely.

Low low low low low low low low,
High high high high high high high high.
Low low low low low low low low,
High high high high high high high high.

Lateral inhibition!
For touch perception, and for vision!
Not just parallel transmission;
It's edge detection with precision.
When a receptor fires,
It turns on branching wires
In lateral inhibition!

• sheet music (with melody play-back)

Songs like this one can be used during class meetings and/or in homework assignments. Either way, the song will be most impactful if students DO something with it, as opposed to just listening.

An initial, simple follow-up activity could be to answer the study questions below. A more extensive interaction with the song might entail (A) learning to sing it, using an audio file and/or sheet music as a guide, and/or (B) illustrating it with pictures, bodily poses, and/or bodily movements. The latter activity could begin with students identifying the most important or most challenging content of the song, and deciding how to illustrate that particular content.

(1) Consult the sheet music for this song. How does the "Low/High" melody illustrate the concept of lateral inhibition?

(2) The song says, "When a receptor fires, it turns on branching wires." What is meant by this?