The data consist of response times and accuracies, and eye movement parameters (e.g., latency to final fixation) from human participants during a series of laboratory tasks. The aim of this project was to advance our understanding of when and why humans succeed and fail to use their "theory of mind" abilities to support interpretation of language. The director task (Apperly et al., 2010; Keysar et al., 2003) was employed in all of our experiments to capture egocentrism during communication in terms of behavioural responses and eye movements. Part 1: effect of overt task instruction on the degree of egocentrism (Exp1: 1-step instruction, Exp2 2-step instruction). Magnitude of common ground varied from 3-9 but data were collapsed over this factor for analysis of effects of instruction. Part 2: cognitive factors associated with perspective-taking (Exp1: magnitude of common ground ranging from 3 to 9 items, Exp2: relative magnitude of common ground versus privileged ground, ranging from 5 to 11 items, Exp3: linguistic complexity in the director’s speech). Part 3: linguistic complexity manipulation with a developmental sample (in press in JECP). Part 4: cross-cultural similarities and differences between English and Taiwanese participants (including an adapted version of the director task with an informed and an ignorant director and a perspective-switching component between these directors). This study also included a level-1 visual perspective-taking task (Samson, Apperly, et al., 2010). We were able to measure altercentric interference, which is spontaneous accounting of other’s perspective, on both tasks. Part 5: memory factor in perspective-taking (there was an additional memory demand on the director task along with systematic variation of the relative magnitude of common ground versus privileged ground between 3 and 9 items. OSPAN was carried out as a working memory measure). Theory of Mind (ToM) is the ability to think about what others see, know, think, want and intend, and is thought to be a fundamental basis of social interaction and communication. ToM has been widely studied in young children and infants, and more recently its cognitive and neural basis has begun to be studied in adults. The main paradigm for this work requires participants to follow instructions from a speaker who does not fully share their visual perspective on the scene under discussion. Critical instructions have different meanings depending on whether or not participants successfully take the speaker's perspective into account. Previous work by the applicants, their collaborator at the University of Chicago, and others, shows that adults frequently show errors when following such instructions, and such difficulty is also observed in more sensitive measures, based on participants' eye movements during the tasks. By adapting these tasks, the new findings will provide insights about: (1) the extent and limits of adults' abilities to use their ToM; (2) how these limits vary between cultures (Western versus Chinese); (3) how they change through children's development into adults; (4) whether people who are good at ToM-use have generally better social abilities.
Computer-based experimental tasks with human participants.
