Quiz 2 (ch.13) Flashcards
Crossed extensor reflex
-Occurs with flexor reflexes in weight-bearing limbs to maintain balance
- Consists of ipsilateral flexor reflex and a contralateral extensor reflex
Stretch Reflexes
- Reciprocal inhibition also occurs
-Example: Patellar reflex
-stretched muscle (quadriceps) contracts and antagonists (hamstrings) relax
plantar reflex/Babinski’s sign
- stimulus: lateral aspect of the foot
◦Response: dorsiflexion of hallux and fanning of toes
◦Present in infants due to incomplete myelination
◦In adults, indicates corticospinal or motor cortex damage
Golgi Tendon Reflexes
- Polysynaptic reflexes
- prevent damage due to excessive stretch
- for smooth onset & termination of muscle contraction
- Produce muscle relaxation in response to tension
Flaccid paralysis
- damage to ventral root or ventral horn cells
- Impulses do not reach muscles; no voluntary or involuntary control of muscles; Muscles atrophy
Spastic paralysis
- damage to upper motor neurons of the
primary motor cortex - Spinal neurons remain intact; muscles are stimulated by
reflex activity; No voluntary control of muscles
Reflex Arc components
- Receptor—site of stimulus.
- Sensory neuron—transmits afferent impulses to CNS.
- Integration center—either monosynaptic or polysynaptic region within the CNS.
- Motor neuron—conducts efferent impulses from integration center to an effector organ.
- Effector—muscle fiber or gland cell that responds to the efferent impulses by contracting or secreting.
longest and largest cranium nerve
vagus nerve (X)
reflex arc
the nerve pathway involved in a reflex action, including at its simplest a sensory nerve and a motor nerve with a synapse between.
how STM is transferred to LTM
- Emotional state
- best if alert, motivated, surprised, and aroused
◦Rehearsal
repetition and practice
◦Association
tying new information with old memories
◦Automatic memory
subconscious information stored in LTM
affected part of quadriplegia
transection in the cervical region
affected part of paraplegia
transection between T1and L1
spinal cord
Location
◦Begins at the foramen magnum
◦Ends as conus medullaris at L1vertebra
dorsal (posterior) nerve root
axons enter the posterior side
◦responsible for sensory functions
ventral (anterior) nerve root
axons exit
◦associated with motor functions
gray horns
◦posterior horn is responsible for sensory processing.
◦anterior horn sends out motor signals to the skeletal muscles.
◦lateral horn, which is only found in the thoracic, upper lumbar, and sacral.
regions, is the central component of the sympathetic division of the autonomic nervous system.
visceral sensory area
◦Posterior to gustatory cortex
◦Conscious perception of visceral sensations
e.g., upset stomach or full bladder
olfactory cortex
the portion of the cerebral cortex concerned with the sense of smell
gustatory cortex
region of the cerebral cortex responsible for the perception of taste and flavor
vestibula cortex
◦Posterior part of the insula & adjacent parietal cortex
◦Responsible for conscious awareness of balance
medulla oblongata
Regulates cardiovascular & respiratory systems & rates
◦Reticular formation related to sleep and wakefulness general brain activity and attention
premotor cortex
- Controls motor skills
- Coordinates simultaneous or sequential actions
planning of movements
primary motor cortex
Allows conscious control of precise, skilled,
voluntary movements
hippocampus and amygdala
involved in long-term memory formation and emotional responses
Broca’s area
production of language, or controlling
movements responsible for speech
