Brain Dysfunction Notes

Brain Dysfunction

Brain dysfunction can be categorized into two main types: structural and functional.

Structural Dysfunction

Structural brain dysfunctions involve physical damage or abnormalities in the brain. Examples include:

  • Stroke

  • Dementia

  • Traumatic brain injury

Functional Dysfunction

Functional brain dysfunctions involve impaired brain function without obvious structural damage. Examples include:

  • Autism

  • Obsessive-compulsive disorder (OCD)

  • Major depression

Acquired Brain Injury

Acquired brain injuries can be further classified as:

Non-Traumatic Brain Injury

  1. Anoxia

  2. Infections

  3. Strokes

  4. Tumors

  5. Metabolic disorders

Traumatic Brain Injury

  • Open Brain Injury (Penetrating Injuries):

    1. Assaults

    2. Falls

    3. Accidents

    4. Abuse

    5. Surgery

  • Closed Brain Injury (Internal Pressure & Shearing):

    1. Assaults

    2. Falls

    3. Accidents

    4. Abuse

Common Neurological Disorders

  • Stroke

  • Traumatic Brain Injury

  • Brain Tumours

  • Movement Disorders

    • Parkinson’s Disease

    • Huntington’s Disease

  • Dementias

    • Alzheimer’s Disease

    • Frontotemporal Dementia

Stroke

Stroke is a leading cause of death and disability. In the UK, approximately 150,000 people experience a stroke each year.

Long-Term Symptoms

  • Hemiplegia (paralysis on one side)

  • Language impairment

  • Executive dysfunction (disinhibition)

Types of Stroke

  • Ischemic Stroke (~80%): Loss of blood flow due to vessel blockage.

    • Thrombotic (~60%): Blood clot formed within the blood vessel, often around atherosclerosis.

    • Embolic (~20%): Clot formed outside the blood vessel travels to the brain and becomes lodged; could be cholesterol build-ups coming from neck blood vessels.

  • Hemorrhagic Stroke (~20%): Bleed from artery into the brain.

    • Blood builds up inside the skull and compresses brain tissue.

    • Some loss of blood flow can also occur.

Ischemic Stroke Locations and Effects

  • Anterior Cerebral Artery (ACA):

    • Affects medial parts of the pre/post central gyrus.

    • Sensory/motor loss.

    • Executive dysfunction.

  • Middle Cerebral Artery (MCA):

    • Affects pre-central (motor) and post-central gyrus (sensory) on one side.

    • Leads to hemi-paralysis and loss of sensation on one side.

    • Can affect language.

  • Posterior Cerebral Artery (PCA):

    • May affect vision, causing blindness.

    • Object recognition problems.

    • Memory problems.

Ischemic Stroke Treatment

  • Acute:

    • Special clot-busting drugs (must be sure it is not a hemorrhage).

    • Must be done early (within 3-4 hours).

    • Early intervention may reduce the extent of the stroke.

  • Chronic:

    • Therapy for physical disabilities.

    • Therapy for language/cognitive difficulties.

    • Adaptation to body/cognitive limitations.

    • Some natural recovery, especially in young people.

Haemorrhagic Stroke

Build-up of pressure within the skull causes brain compression; soft brain tissue and high blood pressure can