Lesson 1: Predisposition, Biological Factors, and the Brain

Biological Causal Factors in Abnormal Behaviour

All behaviour, abnormal or not, is controlled by biochemical processes. Biological factors affect all aspects of behaviour including intellectual capabilities, temperament, stress tolerance, and more. The act of reading this paragraph is activating numerous sensory processes (feeling the paper, having your retinas receive electromagnetic radiation or light), motor processes (moving your eyes, changing the amount of light allowed into your eye), and neuronal processes (the conduction of nerve messages), all of which are mediated by chemical transmissions. Understanding these processes, however, does not account for your motivation to read the information and then think about or understand what is written. To understand these (motivation, thinking, and understanding), one must address the psychological processes driving the behaviour. Biological factors can be categorized into four main areas. Please refer to Figure 5.1 for a graphical overview.