CAS PS 222 Lecture Notes - Lecture 3: Magnetic Resonance Imaging, Absolute Threshold, Electroencephalography
Document Summary
Neuronal level how does an individual neuron respond to a stimulus. Systems level how does an area of the brain respond to a stimulus. Behavioral level how does an organism experience a stimulus. Signal is electrochemical, so we can measure the change in potential of the cell membrane in order to measure the cell"s activity. We can measure the activity of a neuron by looking at the changes in membrane potential (voltage). We take an animal and attach a part of its brain to an electrode system. We create a stimulus (for example, light stimulus) In the absence of stimulus, the neuron has some baseline activity. Each spikes in the diagram is an action potential. Lets say we apply soft pressure: we see the activity of the neuron changing. As we increase the pressure, we get a bigger and bigger change from the baseline ring rate which indicates the signal strength.