HEMISPHERES, SENSORY AND
MOTOR CORTEXES, SPLIT
BRAIN, PLASTICITY,
ENDOCRINE SYSTEM
Chapter 2
Motor Cortex

Motor Cortex – An area at the rear of the
frontal lobes that controls voluntary movements
 Sends
messages from brain to body
 Right Motor Cortex controls movement of left side
of the body
 Page
77
Motor Cortex
Motor Strip Dominance
For each of the following answer left, right, or both.
1.With which hand do you write?
2.With which hand do you throw a ball?
3.Which hand do you use to hold scissors?
4. When holding a baseball bat, which
hand is on top?
5.Which hand deals out playing cards?
Motor Strip Dominance
6.When you cross your arms, which arm is usually on
top?
7.When you cross your leg, which leg is usually on top?
8. When putting on a pair of pants, which leg goes into
the pants first?
9. When putting on a jacket or sweater, which arm goes
into the sleeve first?
10.Which hand is on top when you clap?

High number of right answers means that
you are left strip dominant.
Sensory Cortex

Sensory Cortex – An area at the front of the
parietal lobe that registers and processes
body sensations.
 Receives
messages from the body to the brain
 Right Sensory Cortex receives sensory information
from the left side of the body
 Parts of the sensory cortex receive senses from
various body parts – the more sensitive, the more
cortex area devoted to it.
Sensory Cortex
Phantom Limb

Phantom Limb – feeling sensations or
movements coming from a limb that has been
amputated.
 Ex.
when touching the face of someone whose fingers
have been amputated, the person also reports a
sensation in their nonexistent fingers.
 WHY? Sensations may come from a body image
stored in the brain

Re: p. 83 2nd paragraph Line 9

Phantom Limb Video (till last1:00)
Brain Plasticity

Plasticity – the brains capacity for modification
 Neural
tissue can reorganize as a response to
damage
 Ex. Morgan Madson and Volleyball
 Ex. Child has a right hemispherectomy, now the
functions of the left brain have made new
connections to perform tasks the right brain use to
perform. Picture on p. 83 - Brain Plasticity - the
story of Jody

Girl Living With Half Her Brain
 Children
have more plasticity than adults
Hemispheres of the Brain


Contralateral Control – left hemisphere controls
right side of the body, and the right hemisphere
controls the left side of the body.
2 Students complete CD ROM Activity while class
completes Hemispheric Dominance Inventory
Hemispheres of the Brain

Left Hemisphere
 Receives
sensory messages and controls motor
functions of the right half of the body
 Research indicates the left hemisphere is more active
during logic and sequential tasks and language
Hemispheres of the Brain

The cerebral cortex can be divided into two
hemispheres

Corpus Callosum –
Nerves that connect the
two hemispheres.
Split Brain






Split brain – condition in which the corpus collosum is
severed.
Purpose is to reduce seizures in patients with uncontrollable
epilepsy
Roger Sperry – architect in split brain surgery. (Began by
splitting the brains of cats and monkeys and found no serious
effects)
Split brain patients have “two separate minds” – in textbook,
pg. 85 – Severed Corpus Callosum (ctshad)
Stop at phone..left does not see it…right does..cannot say it
but can write it with left hand.
Psychquest demo on splitbrain CD ROM Activity with word
flashing
Association Areas

Association Areas- Any area of the cerebral
cortex that does not control muscle movements or
receive sensory information – Rather, these areas
involve higher mental functions (learning,
remembering, speaking, and thinking)
Association Areas
Association Areas

Aphasia – impaired use of
language. RE: bottom of p80

Broca’s Area – speech production

Damage to this area may disable muscle
movements needed for speech
Broca's aphasia - Sarah Scott - teenage stroke
 MNEMONIC :BROKEN CD PLAYER
NO LONGER PRODUCES SOUND


Wernicke’s Area – language
comprehension

Damage to this area may disable one’s
ability to understand language


Wernicke's and Broca's Aphasia
Endocrine System



Endocrine System – The body’s “slow”
communication system. This system is made up of
numerous glands that secrete various chemicals,
called hormones, throughout the body. These
hormones affect organs, muscles and other glands in
the body
The Endocrine System: How it Works
Endocrine System (:35)
Endocrine System


Hypothalamus – control center
of the endocrine system.
(specifically controls the adrenal
glands)
Types of Glands


Pituitary Glands (aka “master
gland”)– a pea sized structure
located at the base of the brain.
The pituitary glands regulate and
control other glands. Releases
growth hormone.
Adrenal Glands – produce
adrenaline (also called
epinephrine), regulates the heart
rate and blood pressure. Helps
trigger the fight or flight response.
Endocrine System
 Pancreas
– regulates
levels of sugar in the
blood by secreting
insulin
 Thyroid – located in
the neck, this gland
regulates metabolism
 Ovaries – produce
female sex hormones –
estrogen
 Testes – produce male
sex hormones –
testosterone
Neuroscience review
Psychology Rap
VIDEO- Crash course The chemical brainm (last 3
mins.)
PDF File: Recent Brain Discoveries
If Time, Brain worksheet