Investigating semantic networks used for music and language Processing: Is a cross-domain transfer of skills possible?

The relationship between music and language processing has fascinated scientists for many years and a number of researchers have suggested a positive link between levels of musical expertise and language performance. For example, professional musicians seem to be faster at learning novel words (Dittinger et al., 2016) and artificial sung languages (François & Schon, 2011) than non-musicians. Furthermore, Elmer and colleagues (2014) compared the categorisation of speech, music and neutral sounds between professional musicians, simultaneous interpreters and controls. As might be expected, musicians performed better at musical categorisation and simultaneous interpreters were superior at speech categorisation. However, simultaneous interpreters also performed better at in the music task than controls, suggesting learning transfer across these two domains. Therefore, music and language expertise appear to have bidirectional transfer effects.
But how exactly does skill transfer between music and language occur? Several studies propose that both music and language convey perceptual, semantic and syntactic meaning, and thus musical practice improves language processing due, in part, to training of shared neural networks. However, previous studies have used stimuli that contain both linguistic and musical information, with no attempt to separate the two (e.g. Steinbeis & Koelsch, 2011). Therefore, observed interactions between music and language processing could be due to interference between simultaneously activated networks rather than interference within one network. In fact, there is evidence from brain-damaged patients suggesting that music and language processing to be fully dissociable (e.g. Wilson, Parsons & Reutens, 2006; Ayotte, Peretz & Hyde, 2002). In order to address this paradigm, it is important to separate information and responses provided by linguistic and musical material in both the visual and auditory domains
The aim of this PhD project is therefore to use behavioural and electrophysiological (ERP) measures to investigate brain networks involved in processing semantic information in musical and linguistic material. There are three main research questions: (1) Are the same semantic networks engaged in the processing of musical and linguistic material or can they be separated functionally? (2) Does expertise (musical training or bilingualism) only results in domain-specific processing benefits (e.g., musical training leads to enhanced processing of musical material) or does it also transfer to other domains (e.g., musical training enhances processing of linguistic material). If far-transfer effects are observed, what are the mechanisms facilitating such an effect? (3) Could a short period of musical training benefit populations with language processing difficulties (e.g. dyslexia)?
Importantly, great insight could be gained from investigating semantic networks involved in the processing of both musical and linguistic material in people with learning difficulties, such as dyslexia. Dyslexia is a difficulty in recognizing and reading of words that is believed to stem from perceptual, lexical and/or semantic deficits (Torkildsen et al., 2007). In several linguistic studies using EEG, people with dyslexia show different brain responses compared to controls when processing semantic and syntactic violations (Horowitz-Kraus & Breznitz, 2008; Sabisch et al., 2006; Meng, Tiay, Jian & Zhou, 2007). Interestingly, so far no study has included musical stimuli and explored whether processing deficits found in dyslexia can generalize to musical material. Such finding would not only support the idea of shared music-language processing network but would also suggest that interventions aiming to reduce symptoms of dyslexia could include the training of musical skills.