Exam 5 Flashcards
What are the 2 types of general senses?
*Receptors distributed over a large part of the body
Somatic - located in skin, muscle, joints
Visceral - located in internal organs
What are the 5 somatic senses?
Touch
Pressure
Proprioception
Temperature
Pain
What are the 5 special senses?
*Receptors localized within specific organs
Smell
Taste
Sight
Hearing
Balance
What are the 6 receptors in the skin?
Free nerve ending - pain,temp,itch, proprioception
Merkel disc - light touch/pressure
Hair follicle - light touch /bending of hair
Meissner corpusles - 2 point discrimination
Ruffini end organ - continous touch, pressure, stretch
Pacinian corpuscle - deep pressure vibration proprioception
Sensory neuron uses a how many neuron system?
Ascending
3 neuron
Primary: PNS -> posterior horn
Secondary: Decussate, Spinothalamic tract -> thalamus
Tertiary: Thalamus ->somatic sensory cortex
What are the 4 sensory tracts?
Spinothalamic
Dorsal-Column/Medial-leminscal
Trigeminothalamic
Spinocerebelalr
What does the spinothalamic tract sense?
Pain, temp, light touch, pressure, tickle, itch
What does the dorsal-column/medial lemniscal tract sense?
2 point discrimination, proprioception, pressure, vibration
What are the 2 nuclei in the dorsal column / medial lemniscal tract?
Fasciculus gracilis: inferior to midthoracic
Fasiciculus cuteatus: above midthoracic
What does the Trigeminothalamic tract sense?
what cranial nerve is involved?
Pain, temp, light touch, pressure, tickle, itch, 2 point discrimination for face, nasal cavity, oral cavity
Cranial nerve V - trigeminal nerve
What does the Spinocerebellar tract sense?
Unconscious proprioceptive info
Goes straight to cerebellum
Posterior and anterior tracts
What areas of the brain do our senses go to?
Somatic sensory cortex = posterior to central sulcus
Taste - inferior end of postcentral sulcu
Olfactory = frontal lobe
Auditory = temporal lobe
Visual = occipital lobe
What is Wernickes and brocas area and what do they do?
Wernickes area - Sensory speech - understanding what is heard
Brocas area - sending messages to muscles to make sound
What is Aphasia?
Absent or defective speech or language comphrension. Caused by a lesion
Skeletal neuron uses a how many neuron system?
Decsending
2 neuron pathway
Upper motor: Premotor cortex->interneurons connect to lower motor neurons
Lower motor: Anterior gray horn -> PNS-> Skeletal muscles
What areas of the brain do our motor come from?
Precentral gyrus - primary motor
Premotor area - (anterior to primary motor) - where our motor function are organized before initiation
Prefrontal area - Motivation, foresight to plan and initiate, emotional behavior mood
What are the 2 motor nerve tracts?
Direct (decessates in pyramids): Muscle tone, speed and precision of skilled movements
Indirect: less precise movements
What are the 2 direct pathways for descending motor neurons?
Corticospinal (lateral and anterior): Movements below head
Corticobulbar: movements of head and neck
What are the 3 indirect pathways for descending motor neurons?
Rubrospinal: Red nucleus, regulates fine motor of distal part of upper limb
Vestibulospinal: Exterior muscles in trunk and proximal lower limbs, maintains upright posture
Reticulospinal: Maintenance of posture
What is the cerebellar comparator function?
- Decide what we want to do in primary motor cortex
- Tells cerebellum what it wants to do along with lower motor neuron
- Proprioceptive signals from skeletal muscles and joints to cerebellum convey info about muscles being moved
- Cerebellum modifies info from motor cortex
What are the reflexes in brainstem?
Heart rate, blood pressure, respiration, sleep, swallowing, vomitting, coughing sneezing
also RAS
What is RAS?
Recieves input from Cranial nerves, ascending and descending pathways.
Wakefullness is maintained by info coming from eyes, ears and cerebral cortex
What are the 4 types of brainwaves?
Alpha: Resting state eyes closed
Beta: Intense mental activity
Theta: in adults with frustration or brain disorders, also in children
Delta: Deep sleep, infancy and severe brain disorders
A portion of the dorsal-column/medial lemniscal tract that carries proprioceptive sensations from the nerve endings in the feet and legs is called?
Fasciculus gracilis
Which color represents the primary motor and sensory part of the brain?
Purple - Motor
Yellow - Sensory
What is located in the postcentral gyrus of the parietal lobe?
Primary somatosensory cortex
What is the sequence of info flow in response to bitting into a slice of pizza?
Sensory receptor activated
Impulse sent to CNS
sensation
Perception
What are the differences between Somatic and autonomic systems?
Somatic
- things you can control
- Sensory: Touch, pain, temp, proprioception, special senses
- Motor: Skeletal muscles
-1 motor neuron, uses ACH and is myelinated
Autonomic
- Things you cant control
- Blood vessels, organs, glands
- 2 motor neurons, uses ACH for pregang and either ACH or NE at effector. 2nd is not myelinated