1 Biological, cognitive, and behavioural perspectives
In Week 1, you learned about the evolution of the term dyslexia and the definition of dyslexia, and Week 2 focused on how to identify dyslexia. Building on this knowledge, Week 3 will explore different explanations for the manifestation of dyslexia.
Certainly, there is a complex interplay of different types of influences that collectively contribute to the manifestation of this condition, although a reduced working memory and slow processing skills are common to dyslexia, ADHD and other neuro-differences. To understand it better, we use a framework created by cognitive scientist John Morton and psychologist Uta Frith based on the nature of developmental difficulties, the causal model (Morton and Frith, 1995). The model is a framework that is built upon three interconnected levels: biological, cognitive, and behavioural. It also acknowledges the impact the environment (i.e., the culture in which the person grows up) can have on all three levels. These factors interact to create the behavioural characteristics associated with dyslexia.
Let’s examine each of these in turn.
Biological
This level looks at genetic and brain-related factors that might cause dyslexia. It includes the brain’s structure and function, and any genetic predispositions. Today, dyslexia is mainly seen as having neurobiological origins, meaning it’s related to how the brain works (Wolf et al., 2024).
Cognitive
This level involves mental processes like memory, perception, attention, and speech processing. It explains the mental difficulties that lead to the behaviours seen in dyslexia.
Behavioural
This level provides a model of the difficulty by describing the nature of the behavioural symptoms experienced, e.g. reading difficulties.
Biological and cognitive perspectives offer theories that need testing, while behavioural perspectives are less debated because behaviours can be directly observed. Cognitive perspectives explain how biological and behavioural accounts connect. For example, brain damage (biological) might cause memory issues (behavioural) because the brain can’t transfer information properly (cognitive).
Frith also highlights the environment’s role (see Table 1). Factors like education, culture, and support systems can significantly impact a person with dyslexia, either by making challenges worse or providing essential support.
Wolf et al. (2024) emphasise how environmental factors affect brain development. They suggest that early changes in a child’s environment can impact both their education and brain development throughout life. They believe that changing these environmental factors is crucial in understanding dyslexia.
| Highlighted Biological (Brain’s structure and function, genetic factors) |
|
Environment (External factors, e.g. school system, family support) |
Highlighted Cognitive (Internal processes, e.g. memory, processing speed, language related skills) |
| Highlighted Behavioural/symptomatic (Emotional issues, acting out, resignation) |
Footnotes
Note: this table presents these factors as complementing each other rather than conflictingYou’ll now consider some biological and cognitive explanations for various behaviours, before acknowledging the environmental influences on their development.