Exam 3 (spinal cord, brain, integration)

What are the three major divisions of the brain?

Cerebrum: largest part

Cerebellum: “little brain”

Brainstem: control of autonomic functions

What are the function of the 4 main lobes of the brain?

Frontal lobe: decision making

Parietal lobe: body sense, language

Occipital lobe: Vision

Temporal lobe: Hearing, integration of emotion

What is the function of the cerebellum

Sensory-motor coordination, motor routines, and “muscle memory”

What are the 3 major parts of the brain stem and their functions?

Midbrain: relays sensory & motor information

Pons: relaying sensory/motor information between cerebrum, cerebellum, and spinal cord

Medulla Oblongata: heart rate, breathing, blood pressure

What are the meninges of the brain from outermost to innermost?

Dura mater: double layered with periosteum/subdural space

Arachnoid: arteries and veins, subarachnoid space

Pia Mater: Capillaries

What are the 4 parts of the diencephalon?

Thalamus: information from spinal cord to the right place

Hypothalamus: regulates hunger, thirst, hormone levels, and body temp

Pineal body: sleep/wake cycle

Pituitary gland: secretes hormones

How many pairs of cranial nerves are there, and where do they arise?

12 pairs. All but 2 arise from the brainstem (the rest from the midbrain)

What do cranial nerves carry sensory and motor information for?

The head, face, neck, vision, auditory, taste, and smell

What are the functions of cranial nerves I and II?

I. Olfactory nerve (smell)

II. Optic (vision)

What are the functions for cranial nerves III, IV, and V?

III. Oculomotor: eye movements

IV: Trochlear: eye movements

V: Trigeminal: sensory for face, motor for chewing

What are the functions for cranial nerves VI, VII, and VIII?

VI. Abducens: eye movements

VII. Facial: motor for face, sensory for taste

VIII. Vestibulocochlear: hearing and balance

What are the functions for cranial nerves IX, X, XI and XII?

IX. Glassopharyngeal: motor for tongue/throat, sensory for taste

X. Vagus: Autonomic for heart and lungs

XI. Accessory: Motor for larynx and soft palate

XII. Hypoglossal: motor for tongue muscles

What are the sections of the vertebral column and their counts?

Cervical (neck): 7

Thoracic (chest): 12

Lumbar (abdominal): 5

Sacrum: 5

Coccyx: 4 → 1

How many segments do the spinal cord have?

31, each with a pair of spinal nerves

What does a nerve consist of?

Bundle of axons, blood vessels, and connective tissue

What are the two structural features marking the end of the spinal cord?

Conus medullaris: narrowing right after L2

Cauda Equina: “Horse’s tail”

What are the functions of the three horns in the spinal cord grey matter?

Dorsal horn: sensory (coming in)

Lateral horn: autonomic (out to organs)

Ventral horn: somatic (out to skeleton/muscles)

What is a dermatome?

An area of the body innervated by a single spinal nerve

What happens during a spinal reflex and what part of the CNS in bypassed?

The reflex goes straight to the spinal cord, meaning the brain is completely bypassed.

What are the three types of spinal reflexes?

Stretch: a muscle is rapidly stretched, causing it to contract

Autogenic: strong pull on a tendon, immediate relaxation of a muscle

Flexor: rapid flexion to avoid painful stimulus

What are the three ascending tracts of the spinal

cord and what do they carry?

Dorsal column tract: fine touch and vibration

Spinothalamic tract: temperature, pain, coarse touch to cerebral cortex

Spinocerebellar: body sense information to cerebellum & parietal lobe

What is the difference between parasympathetic and sympathetic branches regarding preganglionic neurons

sympathetic: located in the thoracic & first 2 lumbar segments; secretes acetylcholine; synapse in the sympathetic ganglia parallel to vertebral column (postganglionic releases norepinephrine)

parasympathetic: located in the sacral spinal cord and brainstem; secrete acetylcholine; synpase with neurons in parasympathetic ganglia

What are the functions of the limbic system and reticular system

limbic system: series of nuclei in cerebrum, diencephalon, & brain stem; involved in mood, emotion, and memory (links emotion to movement and smell)

reticular system: diffuse network of nuclei, in the brain stem; responsible for waking up your cerebral cortex