Where the Senses Reside

What am I looking at?

This is an image of several fluorescently labeled interneurons from the hippocampus of a mouse. The neurons in green contain a protein called parvalbumin (1). The neurons in red contain a protein called glutamate receptor subunit GluA4 (2). The neurons in yellow contain both of these proteins (3). And the blue ovals are the nuclei (4) of all the cells present in the sample.

Biology in the background

Groups of neurons in specific brain regions communicate with each other to form neural circuits, which can control or influence specific aspects of our thoughts, emotions, or behaviors. For example, neural circuits in the hippocampus govern learning and memory. To do this, neurons in the brain communicate using electrical and chemical signals. Some of these signals are excitatory, meaning they increase the activity of the neurons that receive the signal. Other signals are inhibitory, meaning they decrease the activity of the neurons that receive the signal.

The interneurons seen here release a neurotransmitter called gamma-aminobutyric acid (GABA), which is a common inhibitory signaling molecule in the brains of mammals. These neurons help regulate the activity of other neurons within the neural circuits of the hippocampus, contributing to the proper function of this brain region.

In both mice and humans, the cell bodies of interneurons are between 12 micrometers and 20 micrometers across, or roughly seven to four times smaller than the width of a human hair.

Technique  

This image was created using confocal microscopy.