Aims - To investigate whether pygmy chimpanzees (bonobos) can aquire human language; To compare the language acquisition in common chimps and pygmy chimps.
Participants - Matata (Bonobo; Original subject for the study; Formally taught via positive reinforcement); Kanzi (Bonobo; Adoptive son of Matata; Learnt via social learning theory; Became key subject of study when he continued to use the lexigram board after Matata left); Mulika (Bonobo; Matata's biological daughter; Learnt via social learning theory); Austin and Sherman (Common chimps; Formally taught)
Design - The chimps were formally taught or watched other chimps using lexigram boards, which contained arbitrary and abstract symbols that lit up when they were pressed and spoke in a synthesised English. The boards also recorded what the chimps were doing. Natural communication wth the researchers was encouraged as they were allowed to forage and explore the 55 acre forest (that contained 17 different locations named after foods such as strawberries) and the inside environement that was not dissimilar to what a human child would be brought up in. The apes were formally tested (e.g. photographs --> lexigrams, words --> photographs, words --> lexigrams, synthesised word --> lexigram) and informally tested (e.g. Kanzi was shown pictures of food and was asked to go to that location in the forest) as well as being observed for two 4.5hr blocks.
Loftus & Palmer II
Aims - To investigate further the effects of leading questions on memory; To see whether leading questions create a response-bias or if they actually alter memory representations; To investigate the influence of post-event information
Participants - 150 new American students, split into three groups of 50 (one control group)
Design - Independent measures design - PPs were shown a one-minute film clip containing a multiple car crash and were asked "About how fast were the cars going when they [smashed/hit] into each other?" (except the control group). One week later, the pps were asked to answer more questions including "Did you see any broken glass?" (There was no broken glass)
Findings - Smashed speed estimate = 10.46mph; Hit speed estimate = 8mph. Smashed = 16 yes broken glass, 34 no; Hit = 7 yes, 43 no; Control = 6 yes, 44 no.
Conclusions - Harsher sounding verbs activated schemas of a car crash which made it more likely for pps to think there was glass. Post-event information can be used to reconstruct a memory of an event and new post-event info can be integrated with original memories.
Aims - To find if adults with autism and normal intelligence would be impared on a new theory of mind test; To test whether, in the general population, males or females are better with ToM.
Participants - Group 1: 13 men and 3 women with autism (HFA) or Asperger's (AS). Group 2: 25 men and 25 women age matched controls with no disorder. Group 3: 8 men and 2 women with Tourette's Syndrome.
Design - Task 1: The Eye's Task = 25 b/w standardised photos of eyes from magazines presented for three seconds so pps could pick the right emotion out of the target and its foil. Task 2: The Strange Stories Task = A comprehension task after pps were told stories which is a validated test for ToM. Task 3: Gender Recognition Task (Control task 1) = PPs had to guess the genders of the eyes from task one. Task 4: Basic Emotions Task (Control task 2) = PPs had to identify the correct emotions of holistic faces out of happy, sad, angry, afraid, disgust and surprise.
Findings - Task 1 = HFA/AS got 16.3/25; No disorder got 20.3/25; Tourette's group got 20.4/25; Males got 18.8/25; Females got 21.8/25. No problems were reported in the control tasks and all results were supported by similar ones in Task 2.
Conclusions - A core deficit of HFA or AS is lack of theory of mind, so they have a problem with reading emotions, but a lack of theory of mind is not present in other developmental disorders such as Tourette's. In the general population, females seem to be better at reading emotions than men, which could be due to nature or nurture. Ultimately, it was found that The Eye's Task is a valid measure of ToM.
Loftus & Palmer I
Aim - To see if participants' estimates for the speed of vehicles in a traffic accident are influenced by the wording of the questions asked.
Participants - 45 American students, split into five groups of nine
Design - Independent measures design - Each group was shown the same seven film clips of car accidents, originally meant as part of a driver safety film and were given a questionnaire after each clip where they had to describe the accident and answer ten questions, including one critical question. The critical question was "About how fast were the cars going when they [verb] each other?" The verbs changed for each group: hit, smashed, contacted, collided and bumped.
Findings - Smashed = 40.8mph average speed estimate; Contacted = 31.8mph average speed estimate
Conclusions - Leading questions can have a negative impact on memory as they can influence recollections of an encoded memory (schema) and harsher sounding words can have a greater impact on memory
Findings - Kanzi performed less well with the synthesised voice but overall, produced 2540 non-imitative combinations and acquired 46 words during the study. He started the study with 8 lexigrams and finished it with 256. Meanwhile, Mulika acquired a still impressive 37 words during the study. Kanzi and Mulika could understand spoken English while the common chimps could not and they could differentiate between specific foods or specific commands that they were given. In addition, Kanzi could understand syntax. The bonobos didn't need facial cues when formally tested while the common chimps did and they also learnt quicker and acquired more words without constant rewarding.
Conclusions - Nature: Bonobos are more able to acquire language than pygmy chimps, signified by a faster rate of understanding, less amount of training needed and complex spoken language and syntax understood. This suggests that bonobos have higher cognitive functioning, possibly due to structural differences in the brains of the chimpanzees. Nurture: The lexigrams were learnt through a process of operant conditioning and learning was increased with the increased exposure to significant role models.