Central Nervous System and the Brain

Central nervous system (CNS)

Contains the brain and the spinal cord.

Peripheral nervous system (PNS)

All of the nerves outside of the brain and spinal cord. It carries messages to and from the CNS

Cerebral cortex

The top part of the brain. It controls consciousness, memory and the senses

Cerebellum

At the back of the brain, controls the body’s balance and muscle coordination.

Hypothalamus

In the middle of the brain, controls body temperature and sends signals to the pituitary gland.

Medulla

At the bottom of the brain, part of the brain stem, control unconscious actives like breathing and heartbeat.

CT scans

Use X-rays showing what areas of the brain are damaged

PET scans

Use radioactive chemicals to measure activity in different parts of the brain.

MRI scans

Use magnetic fields to produce detailed brain structure images

Neurones

Nerve cells that carry electrical impulses from one part of the body to another.

Synapse

A gap in between 2 neurons, passes chemicals between them

Sensory neurones

Carry messages from the receptors like the skin to the CNS

Motor neurons

Carry instructions from the CNS to effectors like muscles or glands

Effectors

Respond by predicting a response like muscles contracting or glands releasing hormones

Reflex arc

How the body acts quickly without thinking. An automatic response to a stimulus to keep you safe.

sympathetic nervous system

prepares the body for exciting and stressful situations. for example eyes dilating, sweating to cool down

parasympathetic nervous system

slows the activity of the heart and respiratory system to restore itself when not in stressful situations.

adrenaline and noradrenaline

involved in the control of sleep, mood and concentration.

acetylcholine

involved in memory and cognition

dopamine

involved in motor control (how we move)

serotonin

involved in the control of sleep and mood, provides the feeling of being happy

GABA

helps the brain to calm down by reducing the signals between neurones.

blood brain barrier

semi permeable membrane that protects the brain from harmful substances in the bloodstream.

parkinson’s disease

a progressive neurological disorder affecting movement. caused by destruction of the dopamine neurons

symptoms of parkinson’s

slowness of movements

muscle tremor

poor balance

stiffness

levodopa

passes through the blood brain barrier where is it broken into dopamine

how does levodopa work

reduces dopamine in the brain. stimulating he dopamine receptors to make more dopamine.

what are the side effects of levodopa

involuntary movements

impulsive and compulsive behaviours.

nausea, loss of appetite, anxiety

advice for patients taking levodopa

warn about the risk of impulsive behaviours.

levodopa can cause sleepiness, driving is dangerous.

don’t stop taking suddenly

how do dopamine agonists work

stimulate the dopamine receptors, mimicking the action of dopamine.

Multiple Sclerosis (MS)

neurological condition cause by damage to the nervous system in the spine and brain.

Myalgic encephalomyelitis (chronic fatigue syndrome)

extreme fatigue ranging from excessive tiredness to joint pain and headaches

huntingtons disease

inherited disease which happens due to the deterioration of brain tissue. it has no cure and is a progressive disease

symptoms of huntingtons disease

difficultly concentrating, memory lapses and change in persona

motor neurone disease

affects the motor neurones in the brain and spinal cords which are responsible for the body’s voluntary movement