How the Brain Works The Facts Visually Explained by DK (z-lib.org)

DISORDERS 196 197

Direct damage to the brain may

occur if both the scalp and the skull

are penetrated. Indirect damage

occurs as a result of a blow to the

head that does not damage the

skull. In both cases, head injuries

can rupture blood vessels, causing

a brain hemorrhage. Minor head

injuries typically produce only mild,

short-lived symptoms, such as a

bruise. In some cases, concussion

may follow, and this may cause

confusion, dizziness, and blurred

vision, which may last for several

Often the cause of epilepsy is

unknown, but in some cases, it may

be due to a brain condition such as

tumor or abscess, a head injury,

stroke, or a chemical imbalance.

Seizures (fits) may be generalized or

partial, depending on how much of

the brain is affected by abnormal

electrical activity. There are several

types of seizures. In a tonic-clonic

(grand mal) seizure, the body

stiffens before uncontrolled

Partial seizure

The person remains conscious,

their head and eyes may turn to

one side, and one hand, arm,

and cheek may tingle or twitch.

Generalized seizure

The person may become

unaware or unconscious. Fits

are brief but may reoccur

rapidly or several times a day.

Epilepsy

Ranging from mild to life-threatening, epilepsy is a brain function

disorder in which there are recurrent seizures or periods of altered

consciousness, caused by abnormal electrical activity in the brain.

Head Injuries

Minor bumps to the head or injuries to the scalp alone

have no long-term consequences. However, injury to the

brain is potentially extremely serious and can be fatal.

THERE ARE ABOUT

60 TYPES OF

EPILEPTIC SEIZURES

BRAIN

SKULL

Partial seizure

may become

generalized

Most or all of the

brain is affected

Only part of the

brain is affected

Brain

impact 1

Brain

impact 2

Blow to

head

Rapid movement

When a person is moving rapidly—for

example, on a bike or in a car—the skull and

brain are moving at the same speed.

Stopping suddenly

On impact, the brain smashes into the

front of the skull, rebounds, and sustains

further injury as it hits the back of the skull.

1

2

days. Postconcussive amnesia can

also occur. Repeated concussions

lead to detectable brain damage,

such as impaired cognitive abilities,

tremors, and epilepsy.

Severe head injury may produce

unconsciousness or coma and

usually brain damage. In nonfatal

cases, the effects of brain damage

may include weakness, paralysis,

poor memory and/or concentration,

intellectual impairment, and even

personality changes. Such effects

can be long-term or permanent.

movements of the limbs and

body begin, lasting up to several

minutes. In absence (petit mal)

seizures, the victim loses

consciousness, although muscle

is retained.

US_196-197_Headache_EpilepsyE.indd 197 20/09/2019 12:39