General Psychology

Matthew 5:5

Blessed are those who hunger and

thirst for righteousness, for they will be filled.

Structure of the Cortex

Each brain hemisphere is divided into four

lobes that are separated by

prominent fissures. These lobes are the

frontal lobe (forehead), parietal lobe (top to rear head), occipital lobe (back head) and temporal lobe (side of

head).

Functions of the CortexThe Motor Cortex is the area at the rear of the frontal lobes that control voluntary movements. The Sensory Cortex (parietal cortex) receives

information from skin surface and sense organs. Different parts control different areas.

Why do the fingers have greater representation than the upper arm?

(Precise Control)

•Try moving your right hand in a circular motion, as if polishing a table.

•Now start your right foot doing the same motion synchronized with the hand.

•Now reverse the foot motion (but not the hand). Tough, huh?

•But easier if you try moving the left foot opposite to the right hand.

•The left and right limbs are controlled by opposite sides of the brain. So their opposed activities interfere less with each other.

Demonstration

Visual Function

The functional MRI scan shows the visual cortex is active as the subject looks at faces.

Courtesy of V

.P. Clark, K

. Keill, J. M

a. M

aisog, S. Courtney, L

.G.

Ungerleider, and J.V

. Haxby,

National Institute of M

ental Health

Auditory Function

The functional MRI scan shows the

auditory cortex is active in patients who

hallucinate.

LanguageAphasia is an impairment of language,

usually caused by left hemisphere damage either to Broca’s area (impaired speaking)

or to Wernicke’s area (impaired understanding).

Specialization & Integration

Brain activity when hearing, seeing, and speaking words

The brain is sculpted by our genes but also by our experiences.

Plasticity refers to the brain’s ability to modify itself after some types of injury or illness.

The Brain’s Plasticity

Our Divided Brain

Our brain is divided into two hemispheres. The left hemisphere processes reading,

writing, speaking, mathematics, and comprehension skills. In the 1960s, it was

termed as the dominant brain.

Splitting the BrainA procedure in which the two hemispheres of the brain are isolated by cutting the connecting fibers

(mainly those of the corpus callosum) between them.

Corpus Callosum

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rtin M

. Ro

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Courtesy of T

erence William

s, University of Iow

a

Split Brain Patients

With the corpus callosum severed, objects (apple) presented in the right visual field can be named.

Objects (pencil) in the left visual field cannot.

Divided Consciousness

Try This!

Try drawing one shape with your left hand and one with your right hand,

simultaneously.B

BC

Right-Left Differences in the Intact Brain

People with intact brains also show left-right hemispheric differences in mental

abilities.

A number of brain scan studies show normal individuals engage their right

brain when completing a perceptual task and their left brain when carrying out a

linguistic task.

Is it All Right to be Left Handed?

Being a left hander is difficult in a right-handed world.

Clockwise Right or Counter Left Brain

Tests

1. Pair up – Poke a hole in a paper and look through the hole.

2. Lean over and whisper to your partner as softly as you can.

Process L/R.

Test

• Need volunteers. Your job is to fool the crowd.

• Are you left or right-handed? You will do a couple of tasks to see if you can fool the crowd.