SYNESTHETIC COLOURS BASED ON VISUAL- AND PHONETIC GRAPHEME SIMILARITY DO NOT GIVE A SIGNIFICANT ADVANTAGE IN LEARNING THE ARABIC ALPHABET ON A SHORT TERM IN DUTCH NON-SYNESTHETES Name student: Kelly Spaans Student number: 11700386 Supervisors: dr. R. Rouw, J. Gudden Examinator: dr. M. Otten Date of submission: 29 January 2021 ABSTRACT The Arabic language plays an essential role in world civilization; however, learning the Arabic script can be quite challenging. Colour coding methods seem to aid in this process, especially for grapheme synesthetes for which graphemes induce colour sensations. For learning a second language in adulthood, the similarity of the visual and phonetic properties to the first language seem to determine the transfer of synesthetic colours to these newly encountered graphemes. Though synesthesia is known to be a predisposed, fixed trait, recent studies have found a possibility for non-synesthetes to acquire synesthetic-like letter-colour associations that differ in colour palette from the non-synesthetic colour palette. In this study we focused on whether ‘synesthetic’ colouring of initial inducers from another alphabetic script (i.e., Modern Standard Arabic) affects the short-term learning process of this script for non- synesthetes. Twenty-one non-synesthetic native Dutch speakers executed a short-term memory task with a within-subject design in which they learned Arabic graphemes. We examined the learning effects of the synesthetic-coloured graphemes in contrast to black graphemes and whether there were any learning differences between colouring these graphemes based on visual or phonetic similarity with the Dutch alphabet. No significant short-term learning effect was found that resulted from synesthetically colouring the novel initial inducers. Moreover, no significant differences were found when these inducers were synesthetically coloured based on visual or phonetic properties. We hypothesize that these results are due to a missing learning curve that is caused by short-term grapheme-learning and an unstable letter-colour association. Therefore, more research into the advantages of synesthetic colouring in non-synesthetes is necessary. Follow-up studies should focus on long-term learning effects in terms of having a greater exposure time to the correct grapheme-sound association as well as the grapheme-colour association. We did not find an appropriate design to learn novel graphemes by using synesthetic colours based on different linguistic properties on short-term notice. However, there are still many possibilities of synesthetic colour-learning methods to explore that especially seem promising for long-term learning. INTRODUCTION With over 240 million native speakers, Arabic is the fifth most learned first language on a global scale (Lewis, Fennig, & Simons, 2009). Thus, it comes as no surprise that the Arabic language plays an essential role in world civilization: from science and commerce, to religion and influences on other cultures. In many European countries, including the Netherlands, the significance of the Arabic language resurfaced specifically with the arrival of refugees and asylum seekers. The majority of these individuals are native Arabic speakers and do not speak any other languages which often creates a language barrier with social workers and makes the integration procedure even more challenging and time-consuming. Though many education programmes currently focus on native Arabic refugees and asylum seekers learning the Dutch language, one should consider providing an education programme for Dutch social workers learning the Arabic language as well. This could lead to a better communication between the two parties and subsequently facilitate the integration process. Whether it is for business or social purposes, learning a new script such as the Arabic script can be quite challenging. Various methods to aid in this learning process have been researched, including colour coding which seems to have an advantage in encoding, storing, and retrieving stimuli (Dzulkifli & Mustafar, 2013). For novel languages in particular, colour coding has shown effects for Indonesian students learning English vocabulary (Nurdiansyah, Asyid, & Parmawati, 2019), children learning modified Hebrew letters (Goodman & Cundick, 1976), and for children discriminating unfamiliar words and letters (Jones, 1965). Furthermore, cases where colours seem to be exceptionally helpful in lexical learning often include grapheme-synesthetes. Synesthesia can be described as a perceptual phenomenon in which a stimulus, the inducer, can induce extraordinary sensations, known as concurrents (Root et al., 2018). The inducer and its subsequent concurrent are often from different modalities (Uno, Asano, Kadowaki, & Yokosawa, 2020), making this phenomenon intriguing from a neurological perspective. A large number of studies have therefore focused on structural and functional brain differences that could cause these types of strong associations. Compared to non-synesthetes, synesthetes showed structural brain differences in white and grey matter properties (Rouw & Scholte, 2007) and altered activation patterns within specific regions of the brain (Sinke et al., 2012). The specific differences are often dependent of the type of synesthesia, as synesthetic experiences can occur between a variety of different modalities. The most common form of synesthesia that includes the visual modality is grapheme synesthesia. In this condition, visual perception of graphemes induce colour sensations (Uno et al., 2020). A model that focuses on structural differences for grapheme synesthesia has been proposed by Hubbard & Ramachandran (2005). This model describes the synesthetic experiences (i.e., perception of colour) as a result of cross-activation, ‘hyperconnections’, within the fusiform gyrus for ‘grapheme’ and ‘colour’ regions. Apart from research into the neurological mechanisms of synesthesia, studies have focused on the psychological effects as well, such as memory advantage. The results from different studies seem to be ambivalent: On the one hand, there are a number of individual cases where exceptional memory seems to be caused by synesthetic experiences (Mills, Innis, Westendorf, Owsianiecki, & McDonald, 2006; Smilek, Dixon, Cudahy, & Merikle, 2002). In a review of Watson, Akins, Spiker, Crawford, & Enns (2014) these advantages are explained in the sense that synesthetes can use their concurrents to obtain and retain information of the initial inducers. On the other hand, based on group studies such as Rothen & Meier (2010), the idea of an ‘extraordinary’ memory advantage is often criticized. Although extraordinary effects have limited evidence, it can be cautiously concluded that there is some sort of memory advantage in the form of ‘superior encoding’ for synesthetes in their specific inducer-concurrent domain (Gross, Neargarder, Caldwell-Harris, & Cronin-Golomb, 2011; Watson et al., 2014). For grapheme synesthetes, the use of colour can be particularly helpful for learning novel graphemes (Blair & Berryhill, 2013). Synesthesia is known to be a predisposed, fixed trait. However, recent studies have found a possibility for non-synesthetes to acquire a subset of certain synesthetic behavioural traits through a training that involved reading in colour (Colizoli, Murre, & Rouw, 2012). The key traits that describe (grapheme) synesthesia are the automatic occurrence in which the sensations appear and their consistency over time (Grossenbacher & Lovelace, 2001) In regard to the concurrents, the colour choices in grapheme synesthetes are often idiosyncratic. However, the full ‘synesthetic’ colour palette is very specific and differs from regular non- synesthetic letter-colour associations (Rouw & Root, 2019). Moreover, there seems to be a certain influence of linguistic properties such as visual form, sound, semantics, and letter frequency on colour choices for specific graphemes (Asano & Yokosawa, 2011). For learning a second language in adulthood, the similarity of the visual and phonetic properties to the first language seem to determine the transfer of synesthetic colours to these newly encountered graphemes (Asano & Yokosawa, 2011; Witthoft & Winawer, 2006). However, the extent to which both of these properties have an impact on this ‘transfer’ varies across writing systems (Asano & Yokosawa, 2013). Transmission of synesthetic colours have been investigated for Glagolitic (Mroczko, Metzinger, Singer, & Nikolić, 2009), Hebrew, Devanagari, Armenian, Cyrillic (Blair & Berryhill, 2013), and even for logographic units (Simner, Hung, & Shillcock, 2011), but not yet for the Arabic language. The Arabic language is closely related to Hebrew, Aramaic, and Amharic (Ryding, 2005). Its spoken form contains multiple varieties of which Egyptian Arabic is used most commonly (Van Leeuwen, Dingemanse, Todil, Agameya, & Majid, 2016). As regards to the written form, Modern Standard Arabic (MSA) is considered the only official form of Arabic and is therefore used mostly in written documents (Van Leeuwen et al., 2016). The Arabic script, written left to right, consists of 28 characters that, independently, mostly represent consonant sounds, with a few semivowels and a few long vowels (Ryding, 2005). Short vowels can optionally be indicated using diacritics above or below the initial characters. however, these are often omitted in MSA (Van Leeuwen et al., 2016). Dependent of their position in a word, or whether they are isolated, the characters