In the first chapter, Hock outlines various studies that reveal the influence of biology on human behavior. For instance, he reviews Michael Gazzinaga’s split-brain research, which identified the separate hemispheres of the brain by cutting the corpus callosum, which is the connecting “bridge” between them.
The area of psychology that studies these biological functions is typically called psychobiology or biological psychology. This field focuses on the actions of your brain and nervous system; the processes of receiving stimulation and information from the environment through your senses; the ways your brain organizes sensory information to create your perceptions of the world; and how all of this affects your body and behavior. The first study discusses a famous research program on right-brain and left-brain specialization that shaped much of our present knowledge about how the brain functions.
The Theory Being Tested:
Hypothesis: Each hemisphere pf the brain is its own conscious system. Both the left and the right hemispheres may be simultaneously conscious in different ways during the same experience.
If the corpus collosum is severed, will the right side of the body be unable to coordinate with the left?
Will the the person be able to comprehend, function and speak properly?
How will the senses of vision, hearing, and touch be affected?
Visual abilities: a picture or word was transmitted to only one visual area (either right or side). If sent to the left side, the eye receptors send the information to the right hemisphere. If sent to the right side, the eye receptors sent the information to the left hemisphere.
a. Pictures of objects or words were displayed to only one eye, affecting only one hemisphere.
b. Another experiment used a row of horizontal lights, and tested which lights the subjects could see with both sides of the brain.
Tactile abilities: The subjects would reach under a table and feel ab object. Sometimes, they would conduct the visual and tactile test simultaneously. They would project a picture of a pen into one hemisphere, and the subject would search for the object among various objects with either hand.
a. A picture was projected on one side of the brain and the subject would have to feel for the object.
Auditory abilities: The subject was asked to grab an item out of a bag with their left hand. Gazzaniga also wanted to know if the surgery affected verbal responses. The subjects were asked to reach into a bag and touch an object, and then explain what they were touching.
a. Gazzaniga told subjects to place different hands in a bag and find different objects.
The left side of a brain is superior in speech, and the right side excels in spatial relations.
Right hemisphere is able to comprehend language, but the left hemisphere of the brain is superior to the right for speech.
Left brain- “better” at speaking, writing, math, and reading and is the primary center for language.
Right brain- possesses superior capabilities for recognizing faces, problem solving.
Examined visual abilities — technique that allowed a picture of an object, in
either the right or left brain hemisphere, but not to both. When your eyes
are fixed on a specific point, images can be fed to the right or left visual
Tactile (touch) stimulation — participants could feel, but not see objects.
They had to reach under a screen and they could touch the objects but not
Auditory abilities — not possible to limit auditory input to only one side of the
brain, but it is possible to limit the response. Asked to pick out an object
from a bag, but both halves of the brain are not equally capable of
responding to this auditory task.
Why the Study Is Important?
We now can see and know the two halves of a brain have assigned skills and functions. The right hemisphere is superior for recognizing faces, solving spatial problems, symbolic reasoning, and artistic activities. The left hemisphere is better at speaking, writing, math calculations, problem solving, reading, and is primary center for language.