LOCALIZATION & LATERALIZATION

OF BRAIN FUNCTION

INTRODUCTION:

The Brain is the only body organ to exhibit both localisation and lateralisation of function.Localization = Different areas of the

brain do different things.

Lateralization = Each brain hemisphere is adapted to certain functions better than the other.

Structure of the Cortex

Why do our brains have so many folds in them?

Four lobes of the cerebral cortex

Frontal• Motor activity• Higher level intelligence• Planning• Problem solving• Emotions• Self-awareness

Parietal• Bodily sensations, e.g., pain, heat• Body movement

Temporal• Hearing• Vision• Smell• Memory

Occipital• Primary visual area of the brain

AN EXAMPLE OF BRAIN

LOCALIZATION:

Different areas of brain associated with same functions.

Broca's area: Articulation of speech. Patients with Broca's aphasia can understand speech but cannot articulate it themselves. Wernicke's area: Understanding language. Patients with Wernicke's aphasia can understand language and reply in fluent, yet garbled or meaningless sentences.

Functions of the CortexThe motor cortex – controls movement of theBody. The motor cortex sends messages fromThe brain to the body. Right side of the brain controls the left side of the body, and vice versa.

Sensory Functions - Receive information fromfrom different senses and in different areas ofthe brain the information is processed.

THE CORTEX

> Emotion and experience, association areas, frontal motor area.

> Sense of touch in different parts of the body.

> Hearing, language and memory for objects.

> Vision.

The cortex is the part of the brainwhich is most strongly associatedwith the mind and generalconsciousness.

BRAIN LATERALIZATION & THE CEREBRAL

HEMISPHERES

Each hemisphere responsible for the opposite side of the body.

Left hemisphere receives information from right field of view and vice versa

Work with split brain patients helped to identify differences in function of the two hemispheres of the brain.

Hemispheric specialization also linked with handedness, in that right handed people have a dominant left hemisphere and so on.