Gerbil Movies:

Gerbil: Pokey

Training Phase: Pokey has successfully learned to use the cup to receive reinforcement and has passed through the stage in which sound is introduced to the task. The flashing light indicates the beginning of a new trial. Once he jumps onto the cup and remains there for a set time, it initiates the presentation of the sound. His presence on the cup is signaled by a photosensitive monitor in the bottom of the cup. For Pokey, /r/ is the positive stimulus and he is being trained to jump in response to /ra/, /ri/ and /ru/ produced by 3 male and 3 female American English speakers. When he remains on the cup (NO-GO) for a pre-determined time in response to an /r/ stimulus he hears a high frequency tone and receives a reward pellet. An error leads to an acoustic buzz and no food reward. In response to /l/, he must jump off the cup (GO) within the pre-determined time to receive the reward. When he makes an error, he must repeat that trial again until correct.

He began his training with only GO trials and slowly NO-GO trials were introduced at very low amplitudes. The amplitude of the NO-GO stimuli was ramped up slightly each day to promote the GO/NO-GO behavior. Pokey is now at the point where the GO and NO-GO stimuli are at the same amplitude. Now that the experimental behavior has been shaped, he has the opportunity to learn the speech category distinction such that his behavior is driven by the category-membership of the speech sounds.

http://www.psy.cmu.edu:16080/~lholt/gerbil/MVI_1984.avi

http://www.psy.cmu.edu:16080/~lholt/gerbil/MVI_1985.avi

Cue Light signaling beginning of trial
Hopper to distribute reward food pellets
Cup from which gerbil receives pellet
Gerbil on platform

(Platform has a photosensitive cell that

detects the gerbil on the cup)

Gerbil: Reggie

Reggie is at the stage of training where the NO-GO stimulus (/r/ in his case) is presented at a lower amplitude than the GO stimulus (/l/).

http://www.psy.cmu.edu:16080/~lholt/gerbil/MVI_1986.avi