Disorders of the nervous system (9)

Question 1

What is Alzheimer’s disease?

Answer 1

It is the incurable, degenerative and terminal disease named after a German psychiatrist, Alois Alzheimer. It is the most common form of dementia - a collective name for loss of mental functioning that affects memory, thinking, behaviour and emotion.

Question 2

What causes Alzheimer’s?

Answer 2

No one actually knows. People believe it is probably caused by a combination of genetic factors and environmental influences. Most attention is being given to the build up of amyloid plaques in certain parts of the brain.

Question 3

How common is Alzheimer’s? (3)

Answer 3

• People of all walks of life may be affected. It is not associated with any particular race, gender or culture.
• Generally associated with people over 65
• It is not an inevitable consequence of getting older

Question 4

What are the symptoms early on?

Answer 4

Short term memory loss.

Question 5

What are advanced symptoms? (5)

Answer 5

• Confusion, irritability and aggression
• Mood swings
• Difficulty in finding the right words
• Long term memory loss
• A general withdrawal from society of the sufferer as their senses decline

Question 6

What is the life expectancy after diagnosis?

Answer 6

Approximately 7 years. The patient dies as body functions are gradually lost.

Question 7

How can the disease be treated?

Answer 7

No cure. Mental stimulation, exercise and a balanced diet are often recommended, as both a possible prevention and a sensible way of managing the disease.

Question 8

What are the 4 steps to drug dependancy?

Answer 8

1. Experimental stage
2. Recreational phase - drugs are only used when offered by friends
3. Regular-use stage - users make sure that they always have a supply of drugs which they use once or twice a week
4. Dependency phase (addiction) - drugs become more important than any other aspect of the user’s life

Question 9

Do all drugs affect the nervous system?

Answer 9

Almost all drugs taken by humans, medicinal and recreational, affect the nervous system. They mainly affect synapses and the functioning of neurotransmitters at a variety of sites.

Question 10

How are drugs classified? (3)

Answer 10

• Hallucinogens
• Stimulants (uppers)
• Depressants (downers)

Question 11

What are hallucinogens?

Answer 11

These are psychedelic drugs that distort reality, resulting in delusions and hallucinations. They cause mood swings that can vary from euphoria to the deepest depression or violence.

Question 12

What are the ‘ups’ of weed?

Answer 12

A sense of relaxation and euphoria

Question 13

What are the ‘downs’ of weed?

Answer 13

Panic attacks, hallucinations, flashbacks and memory less.

Question 14

What does weed contain?

Answer 14

It contains more than 426 known chemicals including the mind-altering substances known as THCs (tetrahydrocannabinol).

Question 15

What does THC do?

Answer 15

It stimulates an increase in the release of the neurotransmitter, dopamine which stimulates the ‘pleasure/reward’ centre in the brain.

Question 16

What are the effects of THC? (4)

Answer 16

• Lack of concentration, causing performance at work, school or university to suffer.
• An ‘a-motivational syndrome’ - a state where the user becomes lethargic, forgetful, anti-social and often losses all ambition and drive.
• ‘Dagga psychosis’ which is caused by excessive use, can result in the following psychotic disorders:
• Exaggerated mood swings
• Excessive agitation
• Hallucinations
• Feelings of persecution
• Suppression of ovulation in women

Question 17

How does the reward system work?

Answer 17

Receptors are stimulated sending impulses to the reward centre in the middle of the brain where the sensation is registered, dopamine is released and we are rewarded by feelings of happiness or pleasure. The memory of this pleasure motivates us to seek more of the initial stimulus.

Question 18

What are depressants?

Answer 18

These drugs suppress or delay brain function.

Question 19

Heroin is produced from the ___ of the opium poppy and is the most dangerous and ___ narcotic.

Answer 19

resin

addictive

Question 20

What is a narcotic?

Answer 20

A suhbtsance which can be habit-forming, dulls the senses, relieves pain or induces sleep.

Question 21

What are the ups of heroin?

Answer 21

A sense of warmth and wellbeing with feelings of pain and insecurity blocked out.

Question 22

What are the down of heroin?

Answer 22

With six to eight hours symptoms such as nausea, vomiting, chills, excessive sweating and muscle and bone pain may develop. The really downside starts with withdrawal symptoms which can set in within two days after the last fix.

Question 23

What are the effects of heroin on the CNS?

Answer 23

Once injected the heroin passes rapidly through the blood-brain barrier and, as it mimics endorphins in the brain, it binds with receptors that were designed for these endorphins. This results in the feelings of bliss and well-being. The brain reacts by releasing fewer of its own endorphins which creates a chemical imbalance resulting in rapid mood changes and confusion.

Question 24

What are endorphins?

Answer 24

A group of hormones in the brain that are released in response to pain or sustained physical exertion (such as running).

Question 25

Explain heroin addiction?

Answer 25

With regular use a tolerance develops, so more and more heroin is needed to achieve the same effects. As higher doses are taken over time, physical dependence and addiction will develop.

Question 26

What are stimulants?

Answer 26

These substances stimulate the brain and increase the heartbeat which results in increased excitability and hyperactivity followed by anxiety and abrupt mood changes.

Question 27

What are the ups of ecstasy?

Answer 27

An enhanced sense of pleasure, increased self-confidence, lots of energy, peacefulness, acceptance and empathy. The high lasts between four and six hours.

Question 28

What are the downs of ecstasy?

Answer 28

Users may develop blurred vision, sweat a lot, clench their teeth and bite the inside of their cheeks, suffer seizures, nausea and vomiting.

Question 29

What are the effects of ecstasy on the CNS?

Answer 29

Ecstasy causes neurons in the brain to release an excess of certain neurotransmitters, particularly serotonin which is not reabsorbed. This results in a depletion of this important neurotransmitter which causes the negative after effects that users experience, eg

• exhaustion and sleep problems
• severe anxiety
• drug craving

Question 30

What is serotonin?

Answer 30

It plays an important role in regulating mood, aggression, sexual activity, body temperature and sleep.

Question 31

What can repeated use of ecstasy lead to? (3)

Answer 31

• Result in extreme depression and paranoia
• Damage the cells that produce serotonin
• Lead to lier, kidney and cardiovascular system failure and finally death due to the dehydration and hyperthermia suffered.

Question 32

What are the ups of tik?

Answer 32

An increased alertness, energy and self-confidence and a heightened sense of sexuality and euphoria.

Question 33

What are the downs of tik?

Answer 33

Withdrawal symptoms leading to aggression, violence and psychotic behaviour.

Question 34

What are the effects of tik on the CNS?

Answer 34

Tik is a stimulant and is highly addictive as it works on the brains reward system. It causes the excessive release of the neurotransmitter, dopamine in the brain. High levels of dopamine stimulate areas of the brain that regulate feelings of pleasure, well-being and elation.

Question 35

What can tik addicts develop?

Answer 35

• Parkinson’s disease
• Psychosis
• Physical and Psychological side effects

Question 36

What is DBS?

Answer 36

Deep brain stimulation (DBS) is a surgery to implant a device that sends electrical signals to brain areas responsible for body movement. Electrodes are placed deep in the brain and are connected to a stimulator device. Similar to a heart pacemaker, a neurostimulator uses electric pulses to regulate brain activity.