How do the left and right hemispheres of the brain work together to create a unified mind? Why do language, attention, memory, emotion, and perception seem to depend more heavily on one hemisphere than the other? And what happens when communication between the two sides breaks down?

This course provides a comprehensive, evidence-based introduction to hemispheric specialisation and inter-hemispheric communication in the human brain. Drawing on cognitive psychology, neuropsychology, and neuroscience, it explores how structural and functional asymmetries arise, how they support efficient information processing, and how they change across the lifespan.

You will examine classic and contemporary findings—from Broca and Wernicke’s discoveries to modern fMRI research—and gain insight into major clinical conditions, including aphasia, hemispatial neglect, extinction, and split-brain syndrome. These phenomena reveal how the hemispheres contribute uniquely to perception, language, attention, and memory, and how the corpus callosum supports coordination between them.

The course also covers how ageing affects the hemispheres, including callosal atrophy and changes in functional organisation. We discuss two leading models—RHAM and HAROLD—to understand how ageing reshapes lateralisation and how the brain compensates for age-related decline.

Taken together, the lectures provide a rigorous but accessible overview of one of the most fascinating topics in neuroscience and cognitive psychology. No prior specialist knowledge is required.