3.4.6—Biological factors

Biological factors include genes, brain structures, neural networks, hormones and neurotransmitters that can influence cognition. They provide mechanisms and constraints, not a complete explanation of every thought or behaviour.

Evidence from drugs, lesions, imaging and genetic comparisons answers different causal questions and has different confounds. Biology interacts with learning, language, culture and environment across development.

A medication that changes receptor activity may improve attention for some people, while sleep, stress and task design also change performance. The biological pathway is part of the explanation, not a single switch.

Biological does not mean fixed or inevitable. Avoid one-molecule stories and state what the evidence actually isolates.

For memory, the hippocampus helps bind elements of an experience into a retrievable episodic representation and supports consolidation with wider cortical networks. Damage can impair formation of new episodic memories while leaving some skills or older memories less affected, showing specialization without treating memory as one location. Lesion evidence supports necessity for particular functions but must be interpreted with damage extent, compensation and task demands.