Experiment 1: Understanding the Impact of Alcoholism on VSPT

All human beings require the ability to clearly navigate through their social worlds, to understand the thoughts, feeling and intentions of others. This human aptitude for reasoning about mental states is known as ToM and has been studied extensively in children and more recently in adults and patients with brain damage (Apperley, 2010 for a review). Having a ToM allows one to understand and predict another person’s behaviour based on their beliefs, desires and intentions. We can reason about others mental states in a slow deliberate fashion, for example, when considering the motives of a suspected criminal in a court of law, but it is also important that we are able to process social information quickly without much cognitive effort in real time social interactions.

ToM may be compromised in adults who have experienced brain damage through accidents, organic lesions and disease. It may also be impaired by alcohol abuse (Evert & Oscar-Berman, 1995; Oscar-Berman, 2000; Oscar-Berman & Marinkovic, 2003; Parsons, 1987). While research has demonstrated that alcohol abuse in adults compromises social processing, such as the recognition and evaluation of emotional stimuli (Clark et al., 2007; Kornreich, et al., 2013; Maurage et al., 2007; Maurage et al., 2008; Townshend & Duka, 2003b), very few studies have directly investigated the relation between alcohol abuse and ToM.

Uekermann et al., (2006) investigated the relation between ToM and alcoholism through the study of humour processing – they reasoned that one needs to understand another’s mind in order to ‘get’ the joke. They found that humour processing was worse in alcoholics compared to non-alcoholics, especially in their ability to answer mentalistic questions regarding the joke scenario.

In a more recent interview/questionnaire study, Bosco et al., (2013) investigated ToM in adults with alcohol use disorder (AUD). Using the Theory of Mind Assessment Scale they found that adults with AUD scored worse than controls when answering a range of questions such as ‘Do you

notice when others feel good? When does that happen? Can you give an example?’ On the basis of the answers provided to 39 questions such as this they argued that the ability to ascribe mental states is impaired in adults with AUD.

While these two studies (and those reported in greater depth in Chapter 3) suggest that social processing is somewhat different in alcoholics, it may be premature to suggest that alcoholics are unable to ascribe mental states to others given that no studies to date have directly assessed their ability to do so. However, even if one accepts the claim that alcoholics are impaired in their ToM processing, these studies only provide evidence for impairment in deliberate and conscious reasoning about mental states. They do not provide evidence that alcoholics are impaired in their ability to rapidly make ToM computations in real time – computations that are relevant to successful ‘online’ social interaction. Thus the aim of the present study was to investigate such processing in alcoholics as well as non-alcoholics.

One such task used to investigate this processing was a visual perspective taking task devised by Zwickel and Müller (2010). They reasoned that a key feature of understanding the mental state of another is in the ability to represent the world from their viewpoint.

In their computerised task participants had to respond to a dot probe which was shown for 500ms to the left or right of a fearful or neutral face (incongruent perspective conditions), or above or below the neutral and fearful faces (congruent perspective condition). Participants had to respond if the dot was on the left or right of the screen, as they saw it. The authors suggested that a slower reaction time (RT) to make the left/right judgement in the incongruent condition, compared to the other conditions was indicative of spontaneous VSPT. A baseline trial displayed blank rectangle instead of a face. It was found that there was indeed an RT cost when the perspective of the dot probe differed from their own and this cost was more pronounced when the face conveyed a fearful expression as opposed to a neutral expression. Zwickel and Müller (2010) concluded that the presence of a fearful face elicits automatic taking of the ‘other’ perspective in a visuo-spatial perspective taking task.

To date, no known research has investigated the impact of alcoholism on VSPT even though alcoholics show deficits in visuo-spatial abilities. Non- alcoholics show rapid engagement with visual stimuli, whereas alcoholics show a delayed response to visual stimuli and this may affect emotional perception (D’Hondt et al., 2014; Butters, Cermak, Montgomnery, & Adinolfi, 1977). Alcoholics are also notably impaired when processing complex facial stimuli e.g., ratings of emotional faces and facial decoding (Maurage, et al., 2008).

Given the findings from the two ToM studies with alcoholics, and the larger number of studies reporting problems processing emotionally charged stimuli, it may be suggested that alcoholics would also be impaired in their ability to consider the perspective of another. Using an adapted methodology from Zwickel and Müller (2010), Experiment 1 investigated whether alcoholism has any effect on visual-spatial perspective taking (VSPT).

To measure VSPT alcoholics were recruited via a charity funded treatment service within the South East of England and compared to non- alcoholics (staff from the treatment service centre) - this distinction was further made by using a questionnaire to identify problematic alcoholic drinking. VSPT was measured by reaction time responses to neutral and fearful faces – a black rectangle acted as a baseline control measure. Stimuli were congruent or incongruent with the perspective of the participant, i.e., if the dot probe was presented to the left/right of the face this was incongruent with the participants perspective, but if presented above/below the face then this was congruent with the participants perspective. A significant adaption between the Experiments within this thesis and Zwickel and Müller’s (2010) is that within these experimental trials participants were not asked to observe or identify the gender of the facial stimuli. This is because the correct identification of the gender of the faces was not in question or of interest in this experiment, there is no evidence in the literature that this may be impaired within alcoholic populations. Secondly, having participants answer the gender questions adds a considerable length of time on to the experimental trials which may affect alcoholics’ motivation, perseverance, attention and ultimately their performance.

4.1.1 Aims of the Experiment

This study aims to assess alcoholics undertaking VSPT. The results show that VSPT occurs spontaneously when the dot probe is presented incongruently with the participant’s own perspective and this effect is more robust when the face is conveying fear. Zwickel and Müller (2010) found no significant difference in reaction times to the dot probe between the baseline and neutral face conditions but there was a difference in reaction time between neutral and fearful faces and this difference was most pronounced when the face conveyed fear. Thus for this experiment, in line with the findings of Zwickel and Müller (2010), VSPT was expected to occur when the dot probe was incongruent to the participant’s perspective, and furthermore when the face was conveying fear.

In Experiment 1 the effect of alcoholism on VSPT is being investigated. This first experiment proposes the question, are alcoholics impaired in automatic perspective taking? If so, can this be added to a growing number of social tasks that alcoholics show differences in their abilities to as compared to non-alcoholics?

4.2 Method