Hemispheric Differences Module 8: The Brain

The Right Brain vs Left Brain test do you see the dancer turning clockwise or anti-clockwise? If clockwise, then you use more of the right side of the brain and vice versa. Most of us would see the dancer turning anti-clockwise though you can try to focus and change the direction; see if you can do it.

Take the Wagner Preference Inventory Scoring: add the number of times each letter is selected. Enter the totals in the large cells in the quadrant at the bottom of the handout. Below the quadrant are two rectangles for total left and right scores obtained by adding (a) and (b) for the left score and © and (d) for the right score. A difference of three points (expressed as a ratio) between L and R is needed to show a significant difference between the functioning of the two hemispheres. Example: dominant left brain = would be 11/1. Balanced would be 5/7

Hemispheric Differences “Left-brained” and “right-brained” debunked Brain is divided into two hemispheres but works as a single entity. Both sides continually communicate via the corpus callosum, except in those with split brains.

Hemispheric Differences: Language and Spatial Abilities Module 8: The Brain

Cerebral Dominance Left Hemisphere – Dominant for: Right Hemisphere – Dominant for: Spatial abilities (piecing together a puzzle, arranging blocks to match designs, reading maps) Face recognition Interpreting gestures Visual imagery Music Left Hemisphere – Dominant for: Language Math Logic Problem Solving – asking questions about the world – making connections. Each hemisphere of the brain is dominant for specific behaviors. This does not mean they “control” these completely. Functions largely overlap – quickly crosses the corpus callosum.

Specialization Broca’s Area – (expressive language) plays a role in production of speech (with motor cortex) If damaged the person can form the ideas but cannot turn those ideas into coherent speech Wernicke’s Area – (receptive language) enables us to understand the spoken and written language.

PET Scan of Broca’s Area

Broca’s Area This is the brain of “Tal” from whom Broca discovered the area for speech. Note the damage to Broca’s Area.

Wernicke’s Area Located in the temporal lobe Involved in language comprehension and expression; our ability to understand what is said to us Usually in the left temporal lobe

PET Scan of Wernicke’s Area

The Brain’s Right Hemisphere Houses the brain’s spatial abilities Our spatial ability allows us to perceive or organize things in a given space, judge distance, etc. Helps in making connections between words

Split-Brain Research Came from epileptic patients Two hemispheres work independently. Left hand doesn’t know what the right hand is doing. Somatosensory cortex in the right hemisphere processes sensation from the left side of the body (left processes information from the right) The left & right share the information which each other in normal brains.

Brain Plasticity Module 8: The Brain

Plasticity The ability of the brain tissue to take on new functions Greatest in childhood Important if parts of the brain are damaged or destroyed