Psych 3L03 Neuroscience Laboratory
PROJECT 1: BRAIN MECHANISMS FOR SKILL LEARNING
INTRODUCTION TO THE PROJECT
Although Long Term Potentiation (LTP) has been proposed as a memory model,
it is often difficult to induce LTP-like change by behaviourial training.
Recently, however, it was done by researchers at Brown University
(Rioult-Pedotti, et al 1998). They trained animals in a reaching task that
required them to learn a skilled movement with their forelimb. By training them
only on one paw, the animals only acquire the skill unilaterally.
If LTP-like phenomenon is serving as the mechanism for this learning, then field
potentials evoked in the trained hemisphere should be larger than those in the
untrained hemisphere. This is exactly what was found. Following training,
evoked field potentials proved to be larger in the trained hemisphere than in
the untrained hemisphere. This is a very important result and researchers in
Dr. Ron Racine's lab at McMaster are now replicating the finding. It appears
that they are actually looking at the change of the brain activity in an intact
animal.
We will monitor activities in horizontal layer 2/3 connections. Five rats
will be trained on the task for five consecutive days. On each day the training
will last for an hour. You have to feed the rats pellets and record how many
times they successfully reach for one and how many times they miss. After the
fifth day of training, evoke potential recordings will be taken from the
animals. Students can watch the recording data being collected. As soon as the
data are collected, the rats will be perfused. Finally, we can stain the brains
with cresol violet to make sure the electrodes are in the right place, but that
will be some time later.
Once we are done there will be two sources of data: 1) the behavioral
results, 2) the field potential results. You will be heavily involved with data
analysis. The staining results will also possibly come from this project (not
to be included in the lab report) later.