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The aim of this study was to establish that the task used to examine spontaneous perspective taking could indeed elicit this effect. Previous stud- ies that used a similar task had focused exclusively on a younger population, specifically in undergraduate students. These results, however, cannot be used as healthy comparison group, as the clinical study was performed on a stroke population, typically of older age, and their performance was expected to differ. Therefore, healthy participants of a similar (older) age were recruit- ed to participate in the pilot study. Additionally, younger adults were also re- cruited, to examine and compare their performance in the task. The pilot study was conducted before and in parallel with the clinical study. It was hy- pothesised that spontaneous 3rd-person perspective taking would occur more in the incongruent condition, followed by the congruent and static ones. No specific predictions about the performance of older compared to young par- ticipants could be made, as the literature has been inconsistent on this topic (e.g. Bernstein, Thornton, & Sommerville, 2011; Happé, F.G., Winner, & Brownell, 1998).

5.3.1. Methods

Participants

A total of 100 participants were recruited. Of these, 52 belonged to the younger healthy controls (YHC) group (22 males; group age range = 18-29 years old, mean age = 23.5 years, SD= 2.89), and 48 participants belonged to the older healthy controls (OHC) group (18 males; group age range = 60- 90 years, mean age = 71.58 years, SD= 9.47). 11 young and seven older participants did not finish the task, as they did not complete the control ques- tions at the end of the procedure (see Materials and procedure section be- low). Participants were recruited on a voluntary basis, via advertisement posters in the University of Hertfordshire, the local voluntary women’s organ-

isation (Women’s Institute) and staff facilities of a UK-based retailer (Marks & Spencer). Exclusion criteria included (1) history of psychiatric or neurological illness; (2) minimum of seven years of education, (3) age (18-30 years old, or 60+ years old). All participants provided written informed consent for their participation. The study was approved by the ethics committee of University of Hertfordshire.

Experimental study design

The main experimental aim of the study was to investigate how differ- ent social cues influence spontaneous perspective taking in young and older adults. This was a 2 (Group: young vs. older) x 3 (Gaze congruency: congru- ent vs. incongruent vs. static) x Perspective taking (front vs. back) design. Gaze was manipulated by means of the videos (gaze-congruent, gaze- incongruent and static, see Materials and procedure).

A control analysis (see Materials and procedures section below) using a 2 (Group: young vs. older) x 2 Instruction (spontaneous vs. directed) x 3 Gaze identification (correct vs. partially correct vs. wrong) was performed. Twelve young and seven older participants did not complete this analysis, and since the number of participants in the spontaneous and directed in- structions conditions became unequal, percentages were used for the statis- tical analysis.

Materials and procedures

For this study a 13-inch laptop and eight videos, duration five seconds each, were used. The videos were filmed using a handy-cam and were cate- gorised as male version (three videos), female version (three videos), or con- trol (two videos). Videos were gender-specific to control for attention and fa- miliarity with the actor that could possibly affect perspective taking. In the male and female versions, the person in the video was sitting behind a table in front of a white wall. The film was recorded in a way that the viewer ap- peared to be sitting on the other side of the table, directly opposite the per- son in the video. The actors wore neutral-coloured clothes and no glasses. On the table in front of the female person in the video was a white bottle of

milk and in front of it was a white mug. Similarly, on the table in front of the male person in the video was a book and in front of the book was a white pen. Items were placed slightly to the left of the actor, to control for left-sided neglect in AHP patients. Videos were categorised into three conditions, ac- cording to the actor’s gaze. In the (gaze) congruent condition, male and fe- male videos started with the actor looking down for 2 seconds, then looking at the item and, while still looking at it, the actor reached and touched the item closest to them (i.e. the book for male version and the milk for the fe- male one) with the right hand. The incongruent condition videos started with the actor looking down for 2 seconds, then looking to their right (i.e. away from the object) and then, while still looking away, the actor reached and touched the object closest to them with their right hand. In the static condition videos, the actor was looking down throughout the video and did not move. Lastly, two additional videos were used, one corresponding to the male and the other to the female version, showing exactly the same setting as the vid- eos described above, but without the actors. These were used as controls at the beginning of the study, to ensure that participants could correctly identify the objects in the videos.

At the beginning of the task, the experimenter placed the laptop on a table in front of the participant and ensured that participants could properly see the screen. The experimenter then read the instructions and prepared the gender-specific videos. The control video (showing the items without the actors) was played first and the participant was asked to name the two items shown in the video. In case of gross misidentification or total failure to recog- nise the items, the experimenter would name them and ask the participant to identify them again. No gross misidentification occurred in this study. The participant was then presented with each of the three gender-specific videos in a pseudo-randomised order, according to which the static video was al- ways shown last. After each video, the participant was asked about the rela- tive position of one item in relation to the other (i.e. “Where is the mug in re- lation to the milk carton?” for females, or “Where is the pen in relation to the book?” for males). If the participant asked for clarifications (e.g. “where is it for me, or for the person in the video?”), or described both perspectives, the

experimenter would encourage them to decide on their own. If the participant gave an answer different than ‘front’ or ‘back’, the experimenter would explic- itly ask for an answer in terms of one of these two options. After seeing all three videos a manipulation check was performed. Participants view the three videos again and afterwards they were asked to report if they noticed any change in the actor’s gaze and their answer was noted. Regardless of their answer, they were asked to see the videos again in a fully randomised order, and this time they were explicitly asked to report any changes in the actor’s gaze in each of the videos. All answers were recorded verbatim.

Statistical analyses

Data were not normally distributed (Shapiro-Wilk p < .000). Since the data used were binary, a Pearson’s chi-square test was used to examine (1) the interaction between Group and Perspective taking; and (2) the interaction of Gaze congruency and Perspective taking within each group.

Additionally, control analysis using a Peasron’s chi-square test was used to examine (1) the interaction between Group and Gaze Identification; and (2) the interaction between Instruction and Gaze identification, within each group.

Figure A: Male video Figure B: Female video

Figure 5.1: Setting and actors used in the videos for the spontaneous perspective task

5.4. Results

5.4.1. Group and Perspective taking interaction

In the young participants group, overall 89.74% of participants an- swered “front” (i.e. took the 1st _{person perspective) and 10.2% “back” (i.e.} took the 3rd person perspective). In the older participants group, the percent- ages were 87.5% and 12.5% respectively. A chi-square test of independence found no significant relation between Group and Perspective taking (χ2 (1, Ν = 300) = 0.375, p = 0.54).

5.4.2. Gaze congruency and Perspective taking interaction

Within the young group, in the Congruent condition, 88% of partici- pants answered ‘front’ (i.e. took the 1PP), and 12% answered ‘back’ (i.e. took the 3rd person perspective). In the Incongruent and Static conditions, 90% of participants answered ‘front’ and 10% answered ‘back’. A chi-square test of independence found no significant relation between Condition and Perspec- tive taking in the AHP group (χ2 (1, Ν = 156) = 0.139, p = 0.933).

Within the older group, in the Congruent condition, 85% of participants answered ‘front’, and 15% ‘back’. In the Incongruent condition, 88% an- swered ‘front’ and 13% ‘back’, while in the Static conditions, the respective percentages were 90% and 10% respectively. A chi-square test of independ- ence found no significant relation between Condition and Perspective taking in the HP group (χ2 (1, Ν = 144) = 0.381, p = 0.827).

5.4.3. Control analysis

12 young and 7 older participants did not complete the control condi- tion and therefore their data were removed from the control analysis.

Within the young group, in the spontaneous instruction condition, 8% of participants answered correct, 50% partially correct and 42% wrong. In the directed instruction condition, 90% answered correct, 30% partially correct, and 0% wrong. A chi-square test of independence found no significant rela- tion between Instruction and Gaze identification in the young participants’ group (χ2 (2, Ν = 200) = 137. 279, p < .000). Regarding the older group, in the spontaneous instruction condition, 6% of participants answered correct, 46% partially correct, and 48% wrong. In the direct instruction condition, 83% answered correct, 17% partially correct and 0% wrong. A chi-square test of independence found no significant relation between Instruction and Gaze identification in the older participants’ group (χ2 _{(2, Ν = 200) = 127. 967, p <} .000).

Overall, the results showed no significant differences in perspective taking between groups or between conditions. However, a difference was found in the control condition, where the majority of participants in the spon- taneous condition answered either partially correct, or incorrectly, while in the directed condition, the majority answered correctly.