lab exam

Electroencephalogram

Measures the electrical activity of the brain

Amplitude

Height of wave, measured in volts

Frequency

Length of wave, measured in hertz

Alpha waves

Commonly produced when the brain is at rest

Beta waves

Commonly produced when the brain is alert and focused (performing a task)

Theta waves

Common in children, an excessive amount in awake adults

Delta waves

Commonly produced in a deep sleep or under anesthesia

Alpha block

When the brain is busy due to focused on a particular task the amplitude decreases

Frequency

Length of the wave, measured in Hz

Reflex

A rapid, predictable, involhntarily response to a stimulus

Knee-jerk reflex

Tapping on patellar ligament, leg extends at the knee

Ankle-jerk reflex

Tapping on calcneal tendon, foot plantar flexes

Plantar reflex

Handle of the reflex hammer to draw along the bottom of the foot to make toes flex

Babinskis sign

Handle of the reflex hammer to draw along the bottom of the foot to make toes extend (abnormal response)

Reflex hammer

The took that is used to stimulate the somatic reflexes

Contralateral response

Opposite side pupil constricts

Ipsilateral response

Same side pupil constricts

Lemon juice

Used to initiate salivary reflex

Outer ear

Captures sound waves

Middle ear

Transmits and amplifies sound waves

Inner ear

Converts sound waves to action potential

Rinne test

Screens for middle ear deafness (conductive deafness)

Rinne test normal response

Air conduction is more sensitive, can hear in front of ear

Rinne test abnormal

No sound infront of ear

Weber test

Screens for inner ear deafness (sensorineural deafness)

Weber test normal response

Volume is equal in both ears

Weber test abnormal response

One ear is louder than the other

Autonomic reflex

Smooth muscle

Somatic reflex

Skeletal muscle

Why the subject should be motionless

To avoid miscle signal artifacts from skeletal muscle