Aims and background
The aim of this project is to advance our knowledge of the cognitive processes that occur during reading of emotional words in individuals who report lower and higher levels of alexithymia. We additionally examine how word concreteness interacts in emotion word processing. Two complementary methodologies are employed. Behavioural measures include reaction times (RTs) to emotion words acquired from a lexical decision task and eye fixation durations obtained from fluent reading of text. The results will provide insights into emotion comprehension in language processing in both normal and atypical populations.
Alexithymia (literally meaning “no words for feelings”) is a normally-distributed personality construct defined by difficulties in identifying and describing emotions, an impoverished fantasy life, and externally-oriented thinking (Sifneos, 1973; Taylor, Bagby, & Parker, 1997). A high level of alexithymia is prevalent in approximately 10% of the population and is considered to be a risk factor associated with a number of psychiatric and psychosomatic disorders including depression and anxiety (Marchesi, Brusamonti, & Maggini, 2000), substance use (Bruce, Curren, & Williams, 2012), schizophrenia (van’t Wout, Aleman, Bermond, & Kahn, 2007), and physical illnesses such as heart disease (Todarello, Taylor, Parker, & Fanelli, 1995).
Alexithymia can be measured via the 20-item Toronto Alexithymia Scale (TAS-20; Bagby, Parker, & Taylor, 1994). A recent German epidemiological study (N=1859) suggested that, instead of the standard threshold score of 61 on the TAS-20 to designate high levels of alexithymia, a less conservative threshold of the 66th percentile (a score of 52.5 in their population) could be used to identify high alexithymics (Franz et al., 2008). For descriptive ease, we will refer to low- and high-scoring individuals as “normal” and “alexithymic”, respectively. In terms of alexithymia research investigating emotion processing, the majority of these studies use pictures as stimuli (e.g., faces), while the studies that have presented words as stimuli typically do so in order to examine memory processes. To our knowledge, no experiment has investigated how the level of alexithymia affects on-line responses to emotion words.
This research project proposes to systematically investigate the processing of positive, negative, and neutral concrete and abstract words in both normal (low-scoring) and alexithymic (high-scoring) populations. Our approach employs two experimental paradigms, namely a lexical decision task (measuring RT and accuracy to individually presented target words) and fluent reading (measuring fixation time on target words embedded in text). These experiments represent an initial examination of potential interactions between the factors of Emotion (positive, negative, neutral), Concreteness (concrete, abstract), as well as Group (normal, alexithymic).