In 1989 Uta Frith noted that most typically developing individuals tend to spontaneously convert sensory elements into meaning in gestalt or overview form, sometimes at the expense of detail (Frith, 1989). Children with autism diagnoses tend to be weak in this ability to "see the big picture", but stronger in detail recognition and processing. At the time, Frith called this weak central coherence1 and it became one of the contenders in the search for a primary mechanism for autism. Indeed the DSM-iv (American Psychiatric Association, 1994) definitions of Autism and Asperger's Syndrome indicate a weakness in central global coherence as a primary diagnostic characteristic. Since the initial proposal of the Weak Central Coherence theory, considerable research suggests that the so called deficit in central coherence may be more complex, possibly indicated as a bias towards strong local coherence (Happé & Frith, 2006; Happé & Booth, 2008; Happé, Briskman & Frith, 2001; Jolliffe & Baron-Cohen, 2001; Kätsyri, Saalasti, Tiippana, von Wendt & Sams, 2008). Work in the music field has indicated that central coherence was not impaired in ASD subjects (Allen, 2010; Allen, Hill, & Heaton, 2009; Mottron, 2000), but overshadowed by local processing on tasks involving picking differences between musical phrases. At the time of writing there appears to be support for this differing balance of ability, epitomised by the concept of Enhanced Perceptual Functioning (Mottron, Dawson, Soulières, Hubert, & Burack, 2006; Mottron, Peretz, & Ménard, 2000). At the time of writing there appears to be support for a differing balance of ability rather than a generalised deficit.
The large image chosen to head this section illustrates the concept visually as attention is concentrated on a single figure within the composition. We are drawn to the intense experience of a single man, not the group context. This focusing to the local is contrived by the construction and context of the image. The camera, through operation of its lenses, provides a literal focal point - the other figures are distorted, literally out-of-focus and serve as a frame for the central character. The eye is also drawn to his centrally located face, seeking understanding of the emotional content, particularly as the image is unnaturally coloured. The image itself is placed and framed within the page, and has an implied title as it has clearly been chosen to represent the chapter and therefore we begin to search for that conceptual relationship. With the tacit instruction to look closer that this paragraph embodies, we look at the various elements of the image and begin to construct its context. It is a group of actors or dancers, they are young, apparently naked, lit with theatrical lights. It is a dramatic performance, we can understand that there is music, an audience, reactions, interplay. The exercise has forced a cognitive process of observation, analysis, access to memory and conscious construction of meaning. In "ordinary" situations, central coherence takes care of much of this for us, spontaneously allowing the individual sensory perceptions to become understanding at a largely sub-conscious level.
For the person with a weak central coherence, or a very strong local coherence, the understanding may remain at the level of a collection of small perceptions without forming a gestalt. If any of these small perceptions is lacking in some way, such as the out of focus performers in our photograph, they may be simply skipped or ignored unless a conscious cognitive effort is made. If we now close our eyes and recall the image, the centrally focused face is likely to be the strongest point in our memory and understanding, perhaps along with the colour. The matter is further complicated by assertions that there are two processes at work in central processing - perceptual, involved in integrating parts of objects such as facial expressions and conceptual, such as that involved in processing language and sentence meanings or collections of memories (Plaisted, Saksida, Alcantara & Weisblatt, 2003). The perceptual aspect is explored in two posts related to facial expression and recognition.
An example can be drawn from the auditory conceptual domain. In conversation we often find ourselves in noisy environments, perhaps a crowded cafe or a classroom next to a busy road. Some words or parts of words spoken by our companion will be masked by other conversations nearby or the sound of traffic. Auditory closure allows us to "fill in" these gaps from the context of the sounds and words within the sentence and the context of the conversation, and helps us recognise sounds and notes within music that are partially masked by other sounds. Weak central coherence can lead to poor auditory closure and a tendency to "tune out" in noisy environments. There is also a tendency to take conversations literally, as the individual meanings of the words over-ride the contextual meaning within a sentence. Many people with ASD have difficulty understanding irony and may be vulnerable to lies (Attwood, 2008, p. 226). They may remember the exact details of a conversation, but not the overall meaning, or its conclusion. On the other hand, they tend to say what they mean, often with great clarity and specific choice of words.
Linguistic processing and the experience of parts of musical meaning share neurological centres (Levitin & Menon, 2003), particularly in the Brodman area. These are sensory stimuli that evolve and create meaning over time as opposed to the more instant stimuli of seeing a tiger or hearing a gunshot. The relevance of this to music becomes clear if we accept that music is a temporal "system of systems". In simplistic form, a sound makes a note, notes make a phrase, phrases make a melody, melodies make a theme, themes make a movement. Classical music has long been the domain of complex structures and complex constructions of formal development are widely considered to be the pinnacle of musical accomplishment. More recent developments building on the ideas of theorists such as Levinson (1997) however argue that large scale form may be somewhat irrelevant if coherence (perceptual understanding) is lacking in the smaller structures. It is argued that in many circumstances "local, small-scale musical units are so rich for aesthetic experience that processing larger musical units may fulfill no crucial need" (Tillmann & Bigand, 2004, p. 219). The succession of and connection between these elements generate the sense of completion at the intuitive, if not the cognitive level. Even within studies such as Tilmman's however, the research is focused on elements within the "working memory" timescale - (something under thirty seconds) with a number of "idea chunks", which might equate to a few phrases in a melodic structure. This suggests that typical appreciation of music via normal central coherence of music will fall within this time domain, after which musical understanding enters into the cognitive domain in terms of structural context.
Children with Asperger's Syndrome have been shown to have a generalised shortening of working memory in the auditory domain (Alloway, Rajendran & Archibald, 2009). Stronger local coherence and a weaker ability to bring elements together is therefore expected to generate focus on musical elements that take less time. This section provides the opportunity to discuss the way that this Central / Local Coherence balance appears to be operating within my own musical life, offering insights into my compositional practice, obsessions with the "sounds of things", and other social aspects that operate around communication and collaboration. This atypical balance provides some distinct advantages to my practice and some unusual approaches to music, each of which have impacts on those around me, collaborators, students, musicians and family.
As discussed elsewhere, <a href="/1208-theory-of-mind"Theory of Mind, which observes a decreased ability to take the perspective of another person, and is central to many observed autistic behaviours, has a discrepancy between real-world observations and clinical testing. Klin's Enactive Mind Theory (Klin et al, 2003) posits a mechanism for ToM deficit based on a diverted developmental pathway, such that the mental enactment of the context of a social interaction, leading to meaningful processing, is not conducted alongside the content of that interaction. An action may be "copied" but not "related to" unless a context for enactment is supplied. Adult and high functioning individuals with ASD, including myself, can and do perform at close to typical levels of ToM under certain circumstances, leading to Klin's initial question "how can they learn so much about the world and yet still be unable to translate this knowledge into real-life social adaptive actions?" (p. 357). The juxtaposition of this concept with Enhanced Perceptual Functioning provides an interesting insight. Should a local perceptual process - visual or aural overwhelm a global one, the time, or perhaps energy, required for enactive thinking to occur under cognitive control, is not present.
This section includes a substantial musical piece, ... in the details which was composed for this thesis. The piece is explored from the point of view of process rather than a traditional musical analysis, and serves to illustrate some of the points raised regarding perceptions of aural detail and the phenomena of obsessive tweaking! Other posts reveal these elements at work within other areas of practice, in the studio and in social contexts.
- the terms central coherence and global coherence are used interchangeably in the literature [↩]
- Insights: This section is titled Insights because I believe that more traditional terms such as "findings", "data" or "discussion" are inadequate.
- Faces and Bits: Prosopagnosia, or face-blindness, can affect both recognition of people and their nonverbal language.
- Social Communication: Social communication deals with the sharing of affect that forms relationships and oils the wheels of conversation sharing.
- Music for the Mind: Music has long been known to improve some aspects of functioning over time.
- The Heart of the Brain: The internal brain structures and pathways appear to have an impact on several aspects of autism, including executive function, the over-riding regulatory mechanisms for cognition and behaviour.
- Speaking, Hearing, Seeing: People with Asperger's and HFA often have unusual ways of speaking, hearing and seeing interpersonal communication modes.
- Composition Processes: A description of compositional process and its relation to local coherence and other factors.