Assessment of the Neurological System

Nervous System Overview

  • Controls body functions through voluntary & autonomic responses.
  • Divided into:
    • Central Nervous System (CNS)
    • Peripheral Nervous System (PNS)

Central Nervous System (CNS)

  • Comprises brain and spinal cord.

Peripheral Nervous System (PNS)

  • Includes nerve fibers outside CNS.
    • 12 pairs of cranial nerves
    • 31 pairs of spinal nerves
  • Carries sensory (afferent) messages to CNS and motor (efferent) messages from CNS.

Cerebral Cortex

  • Frontal Lobe: personality, behavior, motor speech (Broca’s area).
  • Precentral Gyrus: initiates voluntary movement.
  • Postcentral Gyrus: primary sensation center.
  • Occipital Lobe: primary visual center.
  • Temporal Lobe: auditory reception (Wernicke’s area for language comprehension).
Damage Effects
  • Loss of function such as motor weakness, paralysis, loss of sensation, and language processing difficulties (e.g., stroke).

CNS Components

  • Basal Ganglia: subcortical motor system.
  • Thalamus: sensory relay station.
  • Hypothalamus: controls basic functions and HPA axis (fight/flight).
  • Cerebellum: motor coordination.
  • Brainstem: central control of the brain.
  • Spinal Cord: main pathway connecting brain and spinal nerves.

Reflexes

  • Involuntary protective mechanisms:
    • Stretch Reflex: knee jerk.
    • Superficial Reflex: plantar reflex.
    • Visceral Reflex: pupillary response.
Developmental Competence
  • Infants: reliance on primitive reflexes, myelin development.
  • Aging Adults: neuron atrophy, slower nerve conduction, decreased sensory perception.

Health History Assessment

  • Present health status inquiries about mobility, chronic diseases, medications.
  • Past medical history, family history, personal data, and psychosocial factors.

Objective Data Preparation

  • Types of exams: screening, complete, recheck.
  • Sequence: mental status, cranial nerves, motor, sensory, reflexes.
  • Equipment: penlight, tongue blade, cotton swabs.

Cranial Nerves Assessment

  • I - Olfactory (Smell): identify scents.
  • II - Optic (Vision): PERRLA, visual acuity check.
  • III - Occulomotor: pupil reactivity and EOM.
  • IV - Trochlear: downward eye movement.
  • V - Trigeminal: facial sensation, corneal reflex.
  • VII - Facial: facial symmetry and taste.
  • VIII - Acoustic: hearing and balance.
  • IX - Glossopharyngeal: gag reflex and swallowing.
  • X - Vagus: swallowing and speech.
  • XI - Spinal Accessory: shoulder shrug and head movement.
  • XII - Hypoglossal: tongue movement.

Motor System Inspection

  • Assess muscle size, strength, tone, and involuntary movements.
  • Tests for coordination: Romberg test, and knee bending.

Sensory System Assessment

  • Light touch, pain, vibration tests, stereognosis, two-point discrimination.

Deep Tendon Reflexes (DTR)

  • Tested by percussion of tendons.
  • Types: Triceps, Biceps, Brachioradialis, Patellar, Achilles, Plantar.

Neurological Recheck

  • Checking consciousness, motor function, pupillary response, vital signs, and Glasgow coma scale.