Basic building blocks of the nervous system

The way we make connections

Different shapes and sizes but similar structure

Nerve cells (we have 20-100Billion)

Have particular jobs

Cannot see them with our own eyes

Connections that we make at a micro level

They all have specific jobs (approximately 200 different types)

Contains the structure needed to keep the Neurons alive

Short Fibers

Extend root-like from the cell body to receive incoming messages from other Neurons cells

Understand the information

Very thin extension

Transmit impulses to other neurons from branching structures (terminals)

Send the information to knobs

white , fatty substance

Axons of many neurons are wrapped in

protect the axon

At the tips of the axon terminal are swelling

“The glue”

Supporting the neurons

Help with making myelin sheath

Protecting from toxins

Impulses travel from the DENDRITES or cell body through the AXON terminal

can be very quick 250miles/s or slow 2miles/s

Messages are then transmitted from the axon terminal to the dendrites of other neurons

Process by which INFORMATION is passed on

Positive or negative charged particles

Surrounding the cell

semipermeable in normal resting state

Allowing some ions to pass through and not others

When negative ions are inside cell membrane

Positive ions outside

When the cell is at rest

Conduction of neural impulse along the length of the neuron and released into the synapse

Shift from positive to negative voltage (-70 to +40)

Must be large enough to trigger the action potential

Strength of the signal must be strong enough for it to happen

-70 millivolts would change and depolarization would happen

Cell membrane changes to allow sodium ions to enter

Stable state when the cell is not transmitting

Electrical potential across the neural membrane when it’s not responding to other neurons (-70 millivolts)

both positively charged ions such as SODIUM and negatively charged ions such as CHLORIDE

both positively charged particles such as Potassium

More negatively charged particles _____ than outside

Cells go back to being negative charge because they are going to be closed again

Starts to become more negatively charged

when cell membrane actively boots out POSITIVE ions and becomes more negative than it was during resting state

A neuron relay it’s message to another neuron across junction

Small space between

Nerve cells do not touch each other

The AMOUNT of small space between two neurons (1/5000mm)

Chemicals that carry the neural message across the synaptic gap

They all do the same thing

Must get the message across and bring the content back

Neurotransmitters are stored in sacs

neurotransmitter floats across the gap and fits into a specific location on a dendrite called

System that controls all of the activities of the body

Made of: BRAIN, NERVES, SPINAL CORD, SENSES

transmit messages from sensory receptors to the spinal cord and brain

transmit messages from the brain and spinal cord to muscles and glands

connect other neurons Connect sensory and motor

trigger the firing of the next neuron

Allows it to get across

make it more difficult for the next neuron to fire

contains all the neural structures that lie outside of the brain and spinal cord

necessary for us to sense what is going on inside and outside our bodies

Voluntary Muscle Activation

Takes a signal from the outside

sensory receptor (hit your toe)

Collect information through sensory neurons (interneurons)

Pass the message to your body to the next to

Spinal cord to Brain then Bring it back

REACTION

means that you do not have to think about your reactions

Two primary functions:

Controls essential body functions

Regulates emotion

Works in opposition (SNS VS PNS)

GENERALLY ACTIVATES

Activates your body

Open pupils of the eyes

Decreases salivation

Speeds beating of heart

GENERALLY INHIBITS

Bring back your body to generally where you were

Closes pupils of the eyes

Increases salivation

Slows beating of heart

An INTERACTING SYSTEM

controls your emotions, your thoughts, and every movement you make

one hundred trillion synapses in a single human brain organized into exquisitely complex circuits

responding to experience, drugs, disease, and injury

your brain can fix itself

Brain can be restored

Hemispheres

Lobes

Cortex

Hindbrain

Forebrain

Midbrain

Frontal

Parietal

Occipital

Temporal

large band of axons that connect the two hemispheres

work together and share information constantly

Each hemisphere has its own its own responsibilities

Split Half Operations:

different side of the brain and the body

Split Half Operations:

same side of your body same side of the brain

processes information sequentially

described as analytical (e.g. math skills)

specializes in recognizing individual parts which make a whole

Controls language (about 90% of the population), math, and speaking skills

Processes positive emotions

specializes in combining the parts to produce a whole

most efficient at visual and spatial processing

non verbal stimuli are processed here: artistic side, symbolism, processes shapes

Processes negative emotions

executive centre of the brain

involved in decision making, thinking, memory, organization and predicting the consequences of our actions

-largest and least understood

-beginning at the front of the brain and reaching back

-Control body movements "motor area"

part of the "somatosensory area"

it receives information about various bodily sensations

Governs pressure, temperature, taste, pain

Understand spatial orientation

most conspicuous (stands out) lobe of the brain

receives auditory information

controls memory and language

most conspicuous (stands out) lobe of the brain

receives auditory information

controls memory and language

receives and sends out visual information (of the brain) Damage to this area impacts visual perception, recognition, & memory

language comprehension

damaged in the area, makes it unable to understand written or spoken speech

normal speech production

damage to this left patients with the ability to comprehend speech but not to express themselves in words or sentence

layer of grey matter covering the left and right cerebral hemispheres

Outer surface of the brain

Forebrain area, covers Frontal Lobe

highest and most complex integration centre in the human brain

essential function area for "volition"

hard for them to make decisions if damaged

The Relay Station

serves as the sensory relay station in the brain

Sensory input travels to the thalamus where it is redirected to appropriate areas of the cortex

motivational centre of the brain

regulates hunger, thirst, body temperature, etc

Emotional centre of the brain

Works in close harmony with hypothalamus

Emotions and motivation link together

Learning and memory

Often connect with temporal lobe

Fight of flight (frightened), emotions, aggression

to perform routine “housekeeping” functions that keep the body working properly

consists of rich networks of neurons that play roles in influencing wakefulness, arousal level, and attention

Needed for reflexes Breathing, remaining upright

Needed for balance and hearing

Needed for complex muscle movements

Plays a role in memories

Small part on top of the hindbrain

serves primarily as a reflex centre for orienting the eyes and ears

“Gate Keeper”

ascending (to alert) and descending (admit/block) messages

Measuring BRAIN WAVES

measure of the average electrical activity of the brain

associated with : Specific states of consciousness

Cerebral pathology (epilepsy)

One dimensional look at brain

2D and 3D image

Adrian Owen (UofW )

Inside of the brain

Pinpoint changes and blood flow inside the brain

Help determine if patients in comas or vegetative state can understand information