Sensory part II

• Protected by vertebral column
• extends from foramen magnum to 2nd vertebra
• If damaged, paralysis can occur

• H shaped, contains: 
• Posterior horn- contain axons which synapse with interneurons
• Lateral horn- contain autonomic neurons
• Anterior horn -contains autonomic neurons

• Outside of the spinal cord, contains:
• Dorsal column
• Lateral column
• Ventral column

axons that conduct action potentials toward the brain

axons that conduct action potentials away from the brain

occurs when muscles contract in response to a stretching force applied to them

patellar reflex is a classic example of a stretch reflex.

flexor reflex, is to remove a limb or another body part from a painful stimulus.

• 31 pairs, contains:
• Cervical 1-8
• Thoracic 1-12
• Lumbar 1-5
• Sacral 1-5
• Coccyx 1

• Spinal nerves C1-4
• Innervates muscles attached to hyoid bone and neck
• Contains phrenic nerve which innervates diaphragm
• Where neurons come intermingle w/ other nerves

• Originates from spinal nerves C5-T1
• Supply nerves to upper limb, shoulder, hand, axillary,brachial, ulnar

• Originates from spinal nerves L1 to S4
• Supply nerves lower limbs
• Sciatic nerve (longest, largest, nerve)

Dermatome

• Medulla oblongata - Heart, vasomuscular, Respiratory
• Pons - breathing, chewing, salivation, swallowing, relay station between cerebrum and cerebellum
• Midbrain- coordinated eye movement, pupil diameter, turning head toward noise

regulates cyclical motor function, respiration, walking, chewing, arousing and maintaining consciousness, regulates sleep-wake cycle

• attached to the brainstem by the cerebellar peduncles
• means little brain
• cortex is composed of gyri, sulci, gray matter
• It controls balance

• Thalamus- largest portion of diencephalon, influences moods and detects pain
• Epithalamus - above thalamus, emotional and visceral response to odors
• Hypothalamus - below thalamus, controls homeostasis, body temp, thirst, hunger, fear, rage, sexual emotions

• Located at the surface of cerebrum
• controls thinking, communicating, remembering, understanding, and initiates involuntary movements

folds on cerebral cortex that increase surface area

Shallow indentations

deep indentations

• Decussation:
• Left hemisphere controls the right
• Right hemisphere controls the left

connection between the two hemispheres

• Frontal lobe -controls voluntary motor functions, aggression, moods, smell
• Parietal lobe- evaluates sensory input such as touch, pain, pressure, temperature, taste
• Occipital lobe - Vision
• Temporal lobe - hearing, smell, memory

names of ascending tracts usually begin with the prefix spino-, indicating that they begin in the spinal cord, such as the spinothalamic.

• Primary sensory areas:
• where ascending tracts project, where sensations are perceived
• Primary somatic sensory cortex:
• general sensory area in parietal lobe; sensory input such as pain, pressure, temp.

• Somatic motor neurons innervate skeletal muscles.
• maintaining the body’s posture and balance moving the trunk, head, limbs, tongue, and eyes communicating through facial expressions and speech

have cell bodies in the cerebral cortex and project down the spinal cord to synapse with lower motor neurons

have cell bodies in the anterior horn of the spinal cord gray matter or in cranial nerve nuclei.

• Frontal lobe-controls voluntary motor movement
• Premotor area - where motor functions are organized before initiation
• Prefrontal area- motivation and foresight to plan and initiate movement

• are motor tracts carrying impulses down the spinal cord, either terminating there or in the brainstem. 
• Direct- extend directly from upper motor neurons in the cerebral cortex to lower motor neurons in the spinal cord.
• Indirect- they originate in the brainstem but are indirectly controlled by the cerebral cortex, basal nuclei, and cerebellum.

are most important in controlling goal-directed limb movements, such as reaching and manipulating.

such as the reticulospinal tract, are most important for maintaining posture, balance, and limb position through their control of neck, trunk, and proximal limb muscles.

parietal lobe, where words are heard and comprehended

frontal lobe, where words are formulated

• Is where the deep cortical regions and nuclei of the cerebrum and the diencephalon are grouped together.
• Influences long-term declarative memory, emotions, visceral responses to emotions, motivation, and mood.

Meninges

dura mater

subdural space

pia mater

from the lateral ventricles, to the third ventricle, and then to the fourth ventricle

• I. Olfactory- pure sensory nerve for smell (Sensory)
• II.Optic- for vision (Sensory)
• III. Oculomotor - for eye movement (Motor)
• IV. Trochlear- for eye movement (Motor)
• V. Trigeminal- for motor muscles of chewing (BOth)
• VI. Abducens- eye movement (Motor)
• VII. Facial- taste and facial expression (Both)
• VIII. Vestibulocochlear - for hearing and equilibrium (Sensory)
• IX. Glossopharyngeal - for swallowing ( Both)
• X. Vagus - thoracic and abdominal activities (Both)
• XI. Spinal accessory- sternocleidomastoid and muscles of the larynx (Motor)
• XII. Hypoglossal- nerve for the tongue (Motor)

Autonomic nervous system

preganglionic

postganglionic neuron

fight/ flight response

Rest/ digest

carry commands from your brain to your muscles so you can move around.

a component of the peripheral nervous system that regulates involuntary physiologic processes including heart rate, blood pressure, respiration, digestion, and sexual arousal.