M ODULE 4: I NCREDIBLE
N ERVOUS S YSTEM

G
& E
(G
I
)
Fertilization:
 sperm (23) + egg (23) = zygote (46)
Chromosomes:
 contain DNA, every human cells has 23 pairs
Chemical Alphabet:

DNA strand resembles a ladder with 300,000 pgs. of instructions

G
& E
(G
I
)
Genes & Proteins:

Genes- segment of
DNA w/instructions

 eye color, ear lobes, obesity
30,000 human genes on
23 pairs of chromosomes
Genome:
 blue print on how we develop
 gene therapy to treat problems

A. G ENES & E VOLUTION (G ENETIC
I NSTRUCTION )
Evolution of the Human
Brain:
Origins of Species (1859)
Charles Darwin
- theory of evolution
- humans and chimps share at least 98.5% of their DNA
(a) Lucy's Brain (500 grams)
- lived on leaves and fruit
- did not make tools
- no language, or fire
- died out 1 million years ago
- then came "Homo"

A. G ENES & E VOLUTION (G ENETIC
I NSTRUCTION
)
Homo Erectus Brain (1,000 grams)
- added meat to their diets
- stone tools & language developed
- thick skeleton for walking upright
Homo "Sapiens"- means 'wise'
- 400,000 years ago
- 1,350 gram brain
- growing crops, social communities, language
- why?- strong survive/environment
- genetic mutations

A USTRALOPITHICUS A FARENSIS
H OMO E RECTUS

H OMO S APIEN

S TUDYING T HE L IVING B RAIN


Previously we had to study post-mortem now we can see inside the human skull

MRI: Magnetic
Resonance Imaging


 passes non-harmful radio frequencies through the brain incredibly detailed images study the structure of the brain

A. S
T
L
B



 stands for functional measures activity of specific neuron during cognitive tasks
 thinking, listening, reading
 inject radioactive glucose into the blood

 measure amount absorbed by different sections during activity very active brain cells absorb more solution than less active cells

A. S
T
L
B


 uses x-rays to create 3 dimensional images can detect brain damage and highlight cerebral blood flow

C AT S CAN

A. S
T
L
B
 machine parts kept at -
269o C


a couple exist in the world

C. D
T
N
S

M AJOR P ARTS OF T HE B RAIN :

Forebrain
 largest part of the brain (left/right)
 responsible for...






 learning memory speaking and language emotional response sensations initiating voluntary movements planning and decision making

M AJOR P ARTS OF T HE B RAIN

Midbrain

 visual and auditory reflexes reticular formation
 alerts and arouses the forebrain to process incoming information from the senses

M AJOR P ARTS OF T HE B RAIN

Hindbrain

3 distinct structures






Pons
Medulla
Cerebellum
Pons
 makes chemicals involved in sleep.

Transfers messages from spinal cord to brain.
Medulla
 controls vital reflexes
 respiration
 heart rate
 blood pressure.
Cerebellum
 coordinating movements
 timed motor responses, sports and games
 drugs & alcohol slows down this section

H

C ONTROL C ENTER : 4 L OBES

Overall View of the
Cortex

Cortex- in Latin means "cover"

4 lobes- cortex divided into 4 areas

C ONTROL C ENTER : 4 L OBES




Frontal personality

 emotions motor behaviors
Parietal
 perception
 sensory experiences
Occipital

Processing visual info

Temporal
 hearing & speaking

F
L
(E XECUTIVE F UNCTIONS )







 voluntary motor movements interpreting & performing emotional behaviors behaving normally in social situations maintaining a healthy personality paying attention to things in the environment making decisions executive planning, reasoning, carrying out behavior

F
L
(E XECUTIVE F UNCTIONS )

Motor Cortex- narrow strip of cortex on the back of the frontal lobe
 involved in the initiation of all voluntary
 movements
Movements:

Mouth

 vocalization, swallowing, mastication lips, face, eyelids, eyeballs, brow



 fingers hand, wrist, elbow, shoulder, trunk, hip, knee, ankle, toes left hemisphere (cortex) controls right side of the body involved w/memory for the order of events across time

P ARIETAL L OBE
Functions:
 processing sensory information from body parts

 carrying out several cognitive functions attending to & perceiving objects

Somatosensory cortex

Front edge of parietal
 process info about
 touch
 location of limbs
 pain
 temperature

T EMPORAL L OBE F UNCTIONS

Primary Auditory Cortex


Receives electrical signals & transforms them into sounds
 vowels & consonants
The temporal lobe is involved in:

Hearing
 speaking coherently
 understanding verbal & written material

T EMPORAL L OBE F UNCTIONS

Auditory Association Area

Transforms basic sensory information, such as noise or sounds, into recognizable auditory information, such as words or music


Sent from PAC to AAA
Broca's Area (Aphasia) (Frontal Lobe)

 necessary for combining words & sounds & arranging them into manful sentences
Wernicke's Area (Temporal Lobe)
 difficulty in understanding the spoken or written word/ difficulty making sentences if damaged

O CCIPITAL L OBE


Processing visual info
 seeing colors
 recognizing objects
 animals
 people
Primary Visual Cortex

 located at the very back of the occipital lobe receives electrical signals from receptors in the eyes


 transforms these signals into meaningless basic visual sensations seeing colors lights, lines, shadows, & textures

O CCIPITAL L OBE



Visual Association Area

Transforms colors, lights, lines, shadow into people, objects, or animals
Visual Agnosia

Have difficulty combining separate parts to make a whole
Neglect Syndrome

Patient's inability to see objects or parts of the body on the side opposite the brain damage
(shave one side, dress one side)

L IMBIC S YSTEM : O LD B RAIN


1.
Group of interconnected structures that make up the core of the forebrain
Motivational behavior



Obtaining



Food
Drink
Sex
Fear, anger, aggression
Storing memories



Hypothalamus- motivation & emotion
Eating, drinking, sex
Fight or flight
Hormones at puberty

L IMBIC S YSTEM : O LD B RAIN

L IMBIC S YSTEM : O LD B RAIN

Amygdala


Forming , recognizing, and remembering emotional situations (fear)
Emotional facial expressions

Thalamus


Reading and Dyslexia
Receiving sensory information

Initial processing and relaying information to the cortex

Hippocampus


Permanent storage of memories
Remembering facts, places, faces, or conversations

E NDOCRINE S YSTEM

Numerous glands that are located throughout the body and secrete various hormones.

Which affect organs, muscles, and other glands in the body.

E NDOCRINE S YSTEM
1.
2.
3.


Hypothalamus

Controls much of the endocrine system by regulating the pituitary gland which is located directly below and outside the brain
The hypothalamus is often called the control center of the endocrine system


Posterior Pituitary
Regulates water and salt balance
Dysfunction- diabetes
Anterior Pituitary



The front part of the pituitary regulates growth through secretion of growth hormone and
Produces hormones that control the adrenal cortex: pancreas, thyroid, and gonads.

E NDOCRINE S YSTEM
4.
Pancreas
5.


This organ regulates the level of sugar in the bloodstream by secreting insulin
Dysfunction: diabetes or hypoglycemia

Thyroid this gland, which is located in the neck, regulates metabolism through secretion of hormones

E NDOCRINE S YSTEM
6.
7.
Adrenal Gland





Secretes hormones that regulate sugar and salt balances and help the body resist stress (coping)
They are also responsible for the growth of pubic hair, a secondary sexual characteristic
The adrenal medulla (inside part) secretes two hormones that arouse the body to deal with stress and emergencies:
Epinephrine (adrenaline)
Norepinephrine (noradrenaline).
Gonads: Puberty and sexual development


In females, the ovaries produce hormones that regulate sexual development, ovulation, and growth of sex organs.
In males, the testes produce hormones that regulate sexual development, production of sperm, and growth of sex organs.

A UTONOMIC N ERVOUS S YSTEM


Sympathetic Nervous System

Triggered by threatening or challenging physical stimuli


Increases the bodies physiological arousal.
Fight or flight response

Helps the body cope with threatening situations
Parasympathetic Division


Decreases physiological arousal and help return the body to a calmer more relaxed state
Stimulates digestion

Homeostasis

Keeping the body’s level of arousal in balance for optimal functioning

A UTONOMIC N ERVOUS S YSTEM

A UTONOMIC N ERVOUS S YSTEM