Part 2: Acquired Neurcognitive Disorders

Traumatic brain injury: how does it happen?

• Impact → damage at coup (impact site), but worse at contrecoup

TBI: what happens? (1→4)

• Trauma disrupts blood supply to brain tissue through:

  • Bleeding (increased intracranial pressure)

  • Swelling (increased intracranial pressure)

  • Exposure to infection

  • Scar tissues (blocks neural connections)

Length of time blood supply is disrupted for?

• Short, but disruption to neuronal functioning is longer lasting

How can we determine the extent of TBI? (3)

• Longer LOC → worse TBI (bc worse damage → brain needs to be shut down for longer)

• Memory loss

• Loss of vision

etc. etc.

TBI symptoms/consequences? (2) + note

• Diffuse injury (lots of small injuries) → loss of complex cognitive skills due to slower processes

• Frontal + temporal damage → personality change

*Symptoms vary widely based on type + location of injury as well as treatment access + timing

Prevalence of TBI? (2)

• Most common form of brain damage in individuals under 40

• Young men (ages 15–30) being the highest-risk group due to risk-taking and impulsivity.

Golden window for TBI rehabilitation

• Within first 3 months

Cognitive recovery + TBI severity

What happens with repeated concussions or mild TBIs? (1)

• Chronic traumatic encephalopathy (CTE)

CTE def, characteristics (5), common population

• Progressive degenerative disease from repeated TBI

• Neurofibrillary tangles, plaques, neuronal death, cerebral atrophy, ventricle expansion

• Athletes

When can CTE be diagnosed?

Post-mortem

Stroke def

• Sudden interruption in blood flow to brain (ischemia) from blockage/occlusion of a vessel (infarct) or a burst vessel (haemorrhage; aneurysm)

Impacts of stroke (1→3)

• Depends on location but:

  • Cellular changes

  • Inflamed brain tissue → can affect cells far from injury site

  • Reduced metabolism (up to 25%)

Transient ischemic attack (3)

• "mini-strokes,"

• Small, temporary blockages or bursts in minor vessels.

• Brain can sometimes compensate for these, repeated TIAs cause widespread damage over time

How do you identify a stroke

FAST

• Facial droop

• Arm weakness (contralateral)

• Speech (slurred or difficult)

• Time (to call for help)

Symptom of hemorrhagic strokes?

• “Thunderclap headache” (from burst vessel)