Higher Mental Functions

Question 1

What is encompassed in Consciousness?

Answer 1

Perception of sensation

Voluntary initiation and control of movement

Capabilities associated with higher mental processing

- Is superimposed on other types of neural activity: totally interconnected

Question 2

Define Clinical Consciousness

Answer 2

a continuum that grades levels of behavior

awak, alert & oriented – Disoriented – Lethargic – Obtunded – Stuporous – Comatose

Question 3

What is LOC?

Answer 3

Loss of Consciousness

(any loss of consciousness reported as LOC)

Question 4

Describe Brain Waves

Answer 4

• Normal brain function involves continuous electrical activity
• Patterns of neuronal electrical activity recorded are called brain waves
  
  • Each person’s brain waves are unique
  • Change with age, sensory stimuli, brain disease, and chemical states of the body

Question 5

What are the four types of Brain Waves?

Answer 5

Alpha

Beta

Theta

Delta

Question 6

Describe an Alpha brain wave

Answer 6

regular & rhythmic, low-amplitude, slow & synchronous; indicate an “idling” brain

Question 7

Describe a Beta brain wave

Answer 7

rhythmic, more irregular waves occurring during the awake & mentally alert state

Question 8

Describe a Theta brain wave

Answer 8

more irregular than alpha waves; common in children but abnormal in adults

Question 9

Describe a Delta brain wave

Answer 9

high-amplitude waves seen in deep sleep & when RAS input is reduced

Question 10

How is brain wave activity recorded?

Answer 10

through an Electroencephalogram (EEG)

Question 11

What is the unit of measure for brain wave frequency?

Answer 11

Hertz (Hz)

Question 12

Clinical Correlates for Higher Mental Functions

describe EEGs

Answer 12

EEGs are used to diagnose and localize brain lesions, tumors, infarcts, infections, abscesses, and epileptic lesions

- a flat EEG (no electrical activity) is clinical evidence of death

Question 13

Clinical Correlates for Higher Mental Functions

What is Epilepsy?

Answer 13

• Regions of abnormal electrical discharge with physical manifestations
• is not associated with, nor does it cause, intellectual impairments
• often preceded by a sensory hallucination (taste, smell, flash of light); known as an aura

Question 14

Describe a Tonic-Clonic seizure (grand mal)

Answer 14

• Focal point in the motor cortex
• patient will lose consciousness, fall stiffly, and have uncontrollable jerking, loss of bowel and bladder control & severe biting of the tongue
• bones are often broken due to intensity of convulsions

Question 15

Describe an Absence seizure (petit mal)

Answer 15

mild seizures seen in young children where the expression goes blank for a few seconds with brief LOC

Question 16

Describe Epilepsy Treatments

Answer 16

• Can be controlled with anti-convulsive drugs
• Valproic acid, a non-sedating drug, enhances GABA (inhibitory) and is a drug of choice
• Vagus nerve stimulators can be implanted under the skin of the chest or near medulla and can keep electrical activity of the brain from becoming chaotic
• UW researches developed electrode implants that pinpoint locus of seizure (thus focal point of seizure can be removed w/out damaging other areas)

Question 17

How do they treat Intractable Seizures?

Answer 17

severing of the Corpus Callosum is used as a last resort.

Associate problems: R/L hemisphere information transfer significantly minimized; Speech-Language deficites, alien hand syndrome