Sounds of Neuroscience

The neuroscience laboratory is filled with different sounds - crackling from the amplified responses of neurons, scratching of a sliding microtome cutting tissue, the pumping of a respirator.

Watch Oscilloscope

Neuron in the thalamus: Oscilloscope tracing of the activity from neurons in the thalamus (nucleus parafascicularis). Click on the image to the left to start the movie. In the recording, you should be able to see several action potentials with different sizes. There is one large spike and several smaller ones.

Trigeminal Ganglion Cell: this is about 2 seconds of activity that was recorded from a ganglion cell after the maxillary (upper) incisor tooth of an anesthetized rat was tapped 5 times. Listen for 5 distinct "bursts" of action potentials.

Trigeminal Ganglion Cell: this is about 2 seconds of activity that was recorded from a rat ganglion cell after a single whisker (vibrissa) was moved and held in position. Listen for the rapid steady burst of action potentials. This neuron was firing about 100 action potentials every second. The picture below is the actual recording of a portion of what you are hearing...each action potential in this record is separated by about 10 milliseconds. There are 21 action potentials displayed in this picture of the recording - count them!

Sliding Microtome: about 1 second of the sound made by a sliding microtome as it cuts through a frozen brain. A microtome is an instrument that is used to cut thin sections of tissue that will be examined with a microscope. The brain is frozen with dry ice and then cut into sections that are 50 microns thick. After the tissue sections are cut, they are usually stained and mounted on glass slides.

The Microtome

Electronic Microdrive: a few seconds of the sound of made by an electronic microdrive as it advances a electrode into the brain. Every click that you hear is the electrode advancing 1 micron (one thousandth of a millimeter). A microdrive is used to position the electrode in a particular area of the brain for recording activity from neurons.

Electronic Microdrive