Brain psychology

1. Topic:-
Brain and its parts
B.S Mass Communication & maedia

2. Central nervous system
Brain
Central nervous system
The central nervous system (CNS) is the processing center
for the nervous system. It receives information from and
sends information to the peripheral nervous system. The two
main organs of the CNS are the brain and spinal cord,
But we study only brain.
Brain
The brain processes and interprets sensory information sent
from the spinal cord. The brain is the control center of the
body. It consists of three main components: the forebrain, the
midbrain and the hindbrain.
Forebrain
Main regions of forebrain are:
Thalamus
Hypothalamus
Limbtic system
Cerebrum
 Thalamus:
The thalamus is a sensory way station. All sensory information except smell-related data
must go through the thalamus on the way to the cerebrum.
 Hypothalamus:
The hypothalamus lies under the thalamus and helps to control the pituitary gland and
the autonomic nervous system. The hypothalamus plays an important role in regulating
body temperature and biological drives such as hunger, thirst, sex, and aggression.
 Limbic System: The limbic system includes the hippocampus, the amygdala, and
the septum. Parts of the limbic system also lie in the thalamus and the hypothalamus. The
limbic system processes emotional experience. The amygdala plays a role in aggression
and fear, while the hippocampus plays a role in memory.

3.  Cerebrum
The cerebrum, the biggest part of the brain, controls complex processes such as
abstract thought and learning. The wrinkled, highly folded outer layer of the cerebrum
is called the cerebral cortex.
The corpus callosum is a band of fibers that runs along the
cerebrum from the front of the skull to the back. It divides
the cerebrum into two halves, or hemispheres. Each
hemisphere is divided into two deep grooves, known as the
fissure of Rolando and the fissure of Sylvius.There are four
sections or lobe in each hemisphere: the occipital lobe, the
parietal lobe, the temporal lobe, and the frontal lobe:
The occipital lobe: It is located in the very back of our brain, the occipital lobes are
responsible for our eyesight. They contain the primary visual cortex which helps us
interpret the information sent to us by our eyes.
The parietal lobe: It is located above the fissure of sylvius but back the fissure of
Rolando. It contains Sensory Cortex which is located in the front of the parietal lobe
(directly behind the sensory cortex in the frontal lobe), this structure is responsible for
us feeling touch sensations from our body. Every time you feel a type of touch
sensations (both pleasurable and pain) the information is sent up by sensory neurons to
the thalamus and sent to the sensory cortex so we can feel it. The bottom of the cortex
is responsible for the top of our body and the top of the cortex responsible for the
bottom of our body.
The temporal lobe: It is located below the fissure of Sylvius,lying just inside the
temples. It contains the primary auditory cortex, which is involved in processing
auditory information. The left temporal lobe also contains Wernicke’s area.
Wernicke's area is located in our left temporal lobe and is responsible for interpreting
both written and spoken speech. You use Wernicke's area both the read and to listen. If
you damage Wernicke's area (Wernicke's Aphasia) you would be unable to understand
what you are reading or hearing.
The frontal lobe: It is located in front of the brain. There are two specific areas in the
frontal lobe, Broca's Area and Motor Cortex. The left frontal lobe contains Broca’s
area, (at least for most people- in some left handed people, Broca's area is on the right

4. side) which influences speech production. If you damage Broca's area (called Broca's
Aphasia) you will be unable to talk. Motor Cortex is located in the back of the frontal
lobe this thin strip of tissue sends signals (motor neurons) to tell our body to move.
The things we move more (fingers) have more space devoted on the motor cortex, than
parts of us we do not move much (pinky toes). The top of the motor cortex controls
the bottom of our body and the bottom of the cortex controls the top of our body. The
frontal lobe also processes memory, planning, goal-setting, creativity, rational decision
making, and social judgment.
Brain Hemispheres
Lateralization refers to the fact that the right and left hemispheres of the brain
regulate different functions. The left hemisphere specializes in verbal processing tasks
such as writing, reading, and talking. The right hemisphere specializes in nonverbal
processing tasks such as playing music, drawing, and recognizing childhood friends.
Because of the organization of the nervous system, the left hemisphere of the brain
controls the functioning of the right side of the body. Likewise, the right hemisphere
controls the functioning of the left side of the body.
Vision and hearing operate a bit differently. What the left eye and right eye see goes to
the entire brain. However, images in the left visual field stimulate receptors on the
right side of each eye, and in-formation goes from those points to the right hemisphere.
Information perceived by the right visual field ends up in the left hemisphere. In the
case of auditory information, both hemispheres receive input about what each ear
hears. However, information first goes to the opposite hemisphere. If the left ear hears
a sound, the right hemisphere registers the sound first. The fact that the brain’s
hemispheres communicate with opposite sides of the body does not affect most
people’s day-to-day functioning because the two hemispheres constantly share
information via the corpus callosum. However, severing the corpus callosum and
separating the hemispheres causes impaired perception.
Hindbrain
The hindbrain is composed of the medulla, the pons, and the cerebellum.
The medulla lies next to the spinal cord and controls functions outside conscious

5. control, such as breathing and blood flow. In other words, the medulla controls
essential functions.
The pons: It is a Latin word which means bridge. It affects activities such as sleeping,
waking, and dreaming.
The cerebellum: It is a Latin word which means little brain. It controls balance and
coordination of movement. Damage to the cerebellum impairs fine motor skills, so a
person with an injury in this area would have trouble playing the guitar or typing a term
paper.
Midbrain
The midbrain is the part of the brain that lies
between the hindbrain and the forebrain. The
midbrain helps us to locate events in space. It also
contains a system of neurons that releases the
neurotransmitter dopamine. The reticular
formation runs through the hindbrain and the
midbrain and is involved in sleep and wakefulness,
pain perception, breathing, and muscle reflexes.
Methods to study brain function
A variety of procedures are used by physiological psychologists to study the functions
of different areas of the brain. The methods help us to study the localization of the
functional areas of the brain.
Traditional Methods
 lesion
A lesion is the removal or destruction of part of the brain. Doctors will lesion a
patients brain during brain surgery (usually to remove some type of tumor). By
removing parts of the brain we were able to learn what different parts of the brain
do. For example, if a doctor removed a tumor in your left temporal lobe of the brain
and you were then unable to speak, we could assume that speech comes from that
area of the brain. Brain lesions were commonly used in the mid 1900s to control
mentally unstable patients. Part of the frontal lobe was removed (frontal lobotomy)
and drastic behavioral changes occurred after surgery (we learned that our
personalities are strongly centered in the front of our brains).

6.  Stimulation
Stimulation The brain can be stimulated either electrically or chemically. It is
stimulated electrically when electrodes send small electrical pulses to certain parts of
the brain.When certain chemicals are introduced to the brain, they can affect certain
things like hunger or thirst.
 EEG (Electroencephalogram)
The brain is just like an electrical battery. An EEG machine measures brain waves. If
you are awake it measures what we call alpha waves (short active waves) and when
you are asleep it measures other waves like delta waves (long inactive waves). If the
EEG measures no activity then you are either brain dead or watching Jerry Springer.
It is used commonly in sleep research.
Scanning and Imaging Techniques
The advances in modern technology have made it possible to study the internal
workings of the brain without having to cut surgically into a person's skull. The brain
scanning are the mechanical and electrical measurements of biochemical and
electrical activities of specified brain areas. Some of these techniques are discussed
below.
 CAT Scan (Computerized Axial Tomography)
A CAT scan is just a really sophisticated x-ray of the brain. It gives us a 3D picture
of the brain which is great for locating tumors, but it does not show brain activity or
function.
 PET Scan (Positron Emission Tomography)
A PET scan is the best way for us to see activity in the brain. The patient will usually
swallow a substance (like glucose) and the PET scan will see what parts of the brain
are using the substance. If a patient seems to be using alot of the substance in a
certain part of the brain, we can tell what part of the brain is working.
 Magnetic Resonance Imaging (MRI)
It produces a strong magnetic field in which the person's head is positioned. The radio
waves directed at the brain cause the hydrogen atoms to emit signals, which are
analyzed by a computer. The details of the MRI are superior to CAT scan, because it
can distinguish between closely related brain structures.