Do Rats Have the Ability to Discriminate Between Words? Sarah R. Heckendorn and Christina M. Scheele Randolph College Founded as Randolph-Macon Woman’s College in 1891 Lynchburg, VA 24503. Results
Sarah R. Heckendorn and Christina M. Scheele
Founded as Randolph-Macon Woman’s College in 1891
Lynchburg, VA 24503
There was no statistical significant difference in latency to choose a cup choice between the first trial (M=7.49, SD= 7.28) and the last trial (M=8.25, SD= 15.20) for rat 1, t(19)=-0.189, p=0.852. In contrast there was a statistically significant difference between the first latency (M=11.34, SD= 15.95) and last trial’s latency (M=2.94, SD= 1.99) to choose times for rat 2, t(19)=2.311, p=0.032. There was no statistically significant difference between correct cup choice between the first and last day of training for either rat t(19)=0.00, p=1.00, t(19)=-0.52, p=0.61, respectively. The preference index for Rat 1 was 0.15 and was 0.08 for rat 2.
Discrimination is the ability to learn when a stimulus is given a reward can be retrieved (Chance 2006). Studies have showns rats ability to discriminate between tones and no tone in a T-maze (Eninger, 1951) and between two different sounds, such as White noise and FM radio (Sakai & Kudoh, 2005).
However there have been few studies done to find whether rats can discriminate between human words. Will the sounds of the two words left and right alone be enough for rats to learn to discriminate to get a reward? This knowledge could aid in our increasing knowledge of animal intelligence and their ability to understand language.
The subjects were adult, male Long-Evans rats (N=2). Rats were on food deprivation during the length of the experiment but given water freely.
The T-Maze was used with a small plastic cup at the end of each choice arm. The plastic cups contained crushed Froot Loops, with the specific reinforced cup (switched randomly) having six half Froot Loop pieces.
Each Rat was allowed to explore the T-maze for five minutes with 25 half Froot Loops scattered throughout the maze and in the cups during the shaping phase of the experiment. During both shaping and training, instrumental music was played in the background to drown out extraneous noise. Training was then done for five consecutive days; each training day consisted of 20 trials with left and right cup reinforcement switching randomly. The correct reinforcement location, left or right, determined which direction the experimenter would say to the rats. Verbal cues were repeated until the rat made a cup choice (placed it’s head in the plastic cup). If the cup choice was correct the rats were allowed to eat three Froot Loop pieces and then were removed from the maze. If the cup choice was incorrect the rats were allowed to see that the cup was empty and then taken out of the maze. The latency to choose was timed from the first word spoken to the time the rat put its head in the cup to find the Froot Loops. During the test section of the experiment, direction was chosen at random and was continuously verbally given to the rat for two minutes. The amount of time spent in each arm was recorded and a preference index was calculated.
Chance, P. (2006). Learning and behavior: Active learning edition (5th ed.). Belmont, CA: Thomson Wadsworth.
Eninger, M. U. (1951). The rate of learning a tone-no- tone discrimination as a function of the duration at the time of the choice point response. Journal of Experimental Psychology, 41(6). 440-445.
Sakai M., & Kudoh, M. (2005). Characteristics of sound discrimination enhancement after sound exposure in adult rats. Behavioral Neuroscience 119(4). 961-973.