Pepperberg Flashcards
Aim
To see whether a parrot could use vocal labels to demonstrate a symbolic understanding of the concepts ‘same’ and ‘different’.
Research method and variables
animal case study involving one subject who was trained and tested over a couple of years.
Independent Variable
whether the object is familiar or new.
Dependent variable
whether the parrot responds correctly to the questions about ‘what’s same’ and ‘what’s different’ or not.
Sample
Alex, an African grey parrot. Sampled through the opportunity sampling technique.
More detail on Alex
Alex had been involved in prior research on communication and cognition. He could name several colours, shapes, and materials. During the day (8 hours of experimental time), the parrot had free access to all areas of the laboratory, and at night he was confined to a white cage.
Procedure
presented with two objects that could be differentiated based on 3 categories: colour, shape, and the material it was made from. He would then be asked either ‘what’s same?’ or ‘what’s different?’ A correct response would only be recorded if he vocalised the appropriate category and not the 3 categories.
Wht r the 4 processes Alex had to go through to get a correct response
- Attend to multiple features of two different objects.
- From the vocal question, determine if the response is based on similarity or difference.
- Work out what is same or different.
- And vocally produce a category response.
General Training
‘Model-Rival’ technique- One human acts as a trainer and asks the second human questions about two presented objects. A reward is given for the right responses. The second human acts as a model to the parrot but, also as a rival for the trainer’s attention. The roles of trainer/model well frequently reversed. When Alex gave the right vocalisation, he was given a reward/praise rather than to the model. Alex could see the label ‘colour’ and ‘shape’. Alex was trained on the third label “mah-mah,” which meant matter. Training sessions occurred 2 - 4 times per week from 5 minutes to 1 hour.
Testing
Trials were being carried out by secondary trainers who had never trained Alex. On the day prior to the test, the principal trainer would list all possible objects that could be used for testing. A student who is not involved with Alex’s training would choose the question, form the ‘same/different’ object pairs, and randomly order the question. In a week, ‘same/different’ questions were asked between 1 & 4 times (so predictability was low). Testing took place over 26 months. Pepperberg was present for all testing sessions. The same objects were never presented again during the test, so there was a single ‘first-trial’ response. If Alex answered the question incorrectly then the examiner removed the objects, emphatically said ‘NO!’ and turned their head away. But this was presented later till the correct response was achieved. This also taught Alex that an incorrect response meant that he did not get his desired object. The principal trainer during the test procedure sat in the room with her back to Alex. She didn’t look at Alex when objects were presented, she did not know what object was presented, and she repeated out loud what Alex said.
First trial responses
The same objects were never presented again during the test, so there was a single ‘first-trial’ response.
How test scores were calculated:
total number of correct responses ÷ number of trials done.
Results (familiar objects)
- Alex correctly responded to 99 out of 129 trials (76.6%)
- He scored 69 out of 99 (69.7%) on first-trial responses.
Results (Novel objects)
- Alex scored 96 out of 113 (85%) correct responses overall.
- Scored 79 out of 96 (82%) on first-trial responses.
Results (Probes)
Alex scored 55/61 (90%) correct responses overall and 49/55 (89%) on first trial responses.
