Phase III: Retention Probe
A 5-min probe trial is given a couple of weeks after training.The trial begins by placing the rat at 1 of 2 start points around the edge of the Oasis platform. Start points are always in 1 of the 2 quadrants adjacent to the quadrant that contains the training well location. For example, for rats with training wells in the North, start points for the probe trial are either West or East (counterbalanced within each group). No water is available during the probe trial.
Probe trials on the Oasis maze differ in 2 important ways from probe trials in the Morris water maze. First, 5-min probe trials are used, rather than 1-min probe trials, to ensure that rats explore a substantial portion of the Oasis maze. Second, in the Oasis maze rats have a strong tendency to explore the edges of the board and also to return to the start point. For these reasons, chance performance cannot be calculated in a straightforward way.
Chance performance can be estimated by assessing the performance of the RANDOM group (because rats in this group could not acquire a memory for a specific spatial location). To do this, the percentage of time that a trained rat spend within a 58-cm- diameter circle around the trained well is compared with the percentage of time that rats in the RANDOM group spend in this same region (target locations for the RANDOM group are counterbalanced across rats). A 58-cm circle is the diameter of the largest circle that could be completely contained within 1 quadrant of the maze.
Read more about this topic: Oasis Maze
Famous quotes containing the words phase, retention and/or probe:
“The problem of the twentieth century is the problem of the color-line—the relation of the darker to the lighter races of men in Asia and Africa, in America and the islands of the sea. It was a phase of this problem that caused the Civil War.”
—W.E.B. (William Edward Burghardt)
“Unless a group of workers know their work is under surveillance, that they are being rated as fairly as human beings, with the fallibility that goes with human judgment, can rate them, and that at least an attempt is made to measure their worth to an organization in relative terms, they are likely to sink back on length of service as the sole reason for retention and promotion.”
—Mary Barnett Gilson (1877–?)
“Y’know scientists are funny. We probe and measure and dissect. Invent lights without heat, weigh a caterpillar’s eyebrow. But when it comes to really important things we’re as stupid as the caveman.... Like love. Makes the world go ‘round, but what do we know about it? Is it a fact? Is it chemistry? Electricity?”
—Martin Berkeley, and Jack Arnold. Helen Dobson (Lori Nelson)