Two systems for reasoning, two systems for learning Harriet Over and Merideth Gattis School of Psychology, Cardiff University

Social learning Trial error Efficient learning Imitation

Research questions What is the relationship between action imitation and vocal imitation? What can this tell us about the cognitive mechanisms behind imitation?

Insights from action imitation Children’s imitation of actions is related to their understanding of a model’s goals Children copy intentional but not accidental actions (Carpenter, Akhtar & Tomasello,1998; Sakkalou & Gattis)

Two systems for copying actions Perceptual form of behaviour Knowledge of intentions Imitation

2 systems for copying actions Perceptual form of behaviour Knowledge of intentions Mimicry Manipulate mental state information

Carpenter, Call and Tomasello (2002) 2-year-old infants were shown a demonstration of how to remove a pin, and then open the lid of a box Prior intentions Style

Carpenter, Call and Tomasello (2005) 12- and 18-month-old infants Style Objects

Conclusions Imitation reproduce goal Mimicry reproduce irrelevant features

Vocal Imitation How similar are vocal and action imitation? Assumed vocal copying is mimicry (taken from British Library sound archive) Intention understanding?

Experiment 1: vocal imitation and mimicry Aims Design analogous to Carpenter et al (2002) Are there two systems for vocal learning?

Vocal imitation and mimicry Hypothesis: Intention Imitate No intention Mimic

Vocal imitation and mimicry Participants: 22 female undergraduates English first language. Tasks: 1 copy sentences 2 explicit judgement of speaker’s goal (happiness or anger)

Design All information No intonation No words Incongruent cues

When did participants understand the intention? Intonation is the critical cue

Imitation task: dependent variables Imitation: pitch range. - emotion behind speech (Scherer, 1986) Mimicry: Shape of the intonation contour - can express an emotion with different contours (Moziconacci & Hermes, 1999)

Results: Imitation Intonation reproduce intention

Results: Mimicry No intonation irrelevant style

Experiment 2: Reproducing intentions The second system Will children reproduce the intention behind an utterance rather than the specific words they hear?

Imitation in children Meltzoff (1995) 18-month-old children will copy the intended goal of an action Taken from Meltzoff (1995)

‘Failed attempts’ and vocal imitation An ungrammatical sentence is equivalent to a failed attempt to perform an action Slobin and Welsh (1973): 2-year-old subject omitted meaningless repetitions from her imitations -‘Mark fell fell off the horse’ -‘Mark fell off the horse’

Design Participants: 20 children aged 5 and 6 Ungrammatical vs. grammatical sentences Procedure 9 practice trials Test sentences alternated with fillers

Results Children who heard grammatical sentences were significantly more accurate in their reproduction of the test sentences (p<.05)

Results Children in ungrammatical condition were significantly more likely to recast the sentences (p <.05)

Conclusions Children copy the communicative intentions behind speech 2 systems for vocal learning Vocal imitation and action imitation -Cognitively similar -Domain general mechanism

Future studies: 1 Compare reproductions of grammatical repetitions to reproductions of non- grammatical repetitions ‘I thought that that was nice’ ‘It was that that nice day’

Future Studies: 2 Tighten analogy with action imitation Meltzoff Mechanical device Compare imitation of ungrammatical sentences delivered by a intentional agent and a non-intentional agent

Future studies: 3 Will children reproduce redundant information? Memory load

Dual Processes System 1: associative, holistic, automatic, undemanding of cognitive capacity, acquisition by biology, contextualised System 2: controlled, demanding of cognitive capacity, analytic, slow, acquisition by tuition. (Evans, 2006; Over, 2000)

Mimicry – System 1 Evolutionarily old Shared with many other species

Imitation – System 2 evolutionarily recent and potentially species unique Domain general flexible knowledge – general purpose blade

Predictions Higher individual differences in tendency to imitate individual differences in imitation should be correlated with IQ and working memory capacity Imitation but not mimicry should be impaired by placing demands on working memory

Individual differences Questionnaire: tendency to imitate (Sakkalou & Gattis)

Working memory Goal-directed theory (Bekkering, Wohlschlager & Gattis, 2000) Processing multiple goals (Perra & Gattis, 2006) Taken from Bekkering et al (2000)

Thank you Thanks to: Elena Hoicka Elena Sakkalou Oliver Perra