SOLUTIONS
4 stages of sleep Correct Answers REM- your eyes move, you
dream, your muscle tone vanishes (you don't act out in your
dreams so you don't injury yourself)
-brain waves 30-40 Hz (faster/higher frequency)
-only birds and mammals have REM sleep, aquatic mammals
don't because without muscle tone they would drown
non REM (NREM) sleep- dreamless, with slower brain waves, it
has 3 stages (1-3) where stage 3 is deep NREM with regular 2-4
Hz brain waves
-the stages follow each other in a 90 minute cycle (stepwise
fashion)
-the first REM stage occurs after about 90 minutes of sleeping.
As the night progresses NREM sleep gets shallower and REM
stages longer and you may wake up occasionally
-each time you enter REM stage, it lasts for longer
a monosynaptic reflex loop Correct Answers -has a single
synapse between the afferent (sensory) and efferent neurons
(motor) to produce a response
-example: spinal reflex, integration occurs at the spinal cord
without input from the brain
amplitude Correct Answers the pressure difference between
peak and trough
,-the main factor that determines our perception of loudness: the
larger the amplitude, the louder he sound (for any one sound
frequency)
-loudness depends on frequency (and amplitude) as well (ie a
sound of 30,000 Hz is beyond the range of human hearing, so it
won't be loud no matter how large its amplitude
analgesics Correct Answers pain relievers
Acetylsalicylic acid (aspirin) inhibits prostaglandins (detected
by some nociceptors) and inflammation which released
chemicals detected by nociceptors and slows transmission of
pain signals
opioids (ie morphine and codeine) decrease transmitter release
from primary sensory neurons and postsynaptically inhibit
secondary sensory neurons
-resemble natural pain killers- thats why they have a strong
effect in the body
-the body makes natural pain killed such as endorphins,
enkephoalins and dynorphins
arm swings Correct Answers -CPGs in cervical cord program
motion of arms during walking
-flexion phase synchronous with contra-lateral flexion in leg-
diagonal pattern to cancel torque on trunk (when one leg is
flexing, the opposite arm is flexing)
-phase linking via propriospinal tracts between the legs and the
arms (from one segment of cord to another- link the lumbar
portion of the spinal cord where the legs are with the cervical
,region of the spinal cord where the legs are). This links and leg
and arm CGPs together to set proper motion of legs and arms
while walking
auditory processing Correct Answers auditory signals pass from
each ear to both sides of the brain via the cochlear nerve to the
medulla. The cochlear nuclei get info from only one ear
-for all stages of processing after the cochlear nuclei, the
neurons get info from both ears
-midbrain to thalamus (medial geniculate nuclei) to the primary
auditory cortex in the temporal lobe
autonomic nervous system Correct Answers
babinski sign Correct Answers -extensor thrust reflex is
influenced by corticospinal tract (descending axonal tract)
-can be elicted at rest (in the toes) by vigorously stroking of sole
of foot and the toes will bend downwards- normal anti-gravity
extension to help support your weight so you stand up
-if corticospinal tract is damaged (ie during a stroke, spinal
injury), the reflex pattern is switched to flexion withdrawal (no
longer an extensor thrust pattern- the toes is curling up instead
of down)
-test this reflex to see if there are problems with the
corticospinal tract
basilar membrane Correct Answers -responds to different
frequencies at different points
-the membrane is narrow and stiff near the round and oval
windows, wider and more flexible as its other end
, -high frequency waves maximally displace the membrane at the
oval window end; low frequency waves maximally displace the
other end. So the brain can deduce the frequency by noting
which hair cells are most active at points of the membrane
broca's area Correct Answers premotor zone for sequencing
language elements for speech or writing-typing
-get input from wernicke's area (where language elements are
recognized)
central hearing loss Correct Answers there is damage to the
cortex of the pathways from cochlea to cortex.
-typically, the patient's trouble is in recognizing and interpreting
sounds rather than in detecting them- they could hear soft or
loud sounds- they can't interpret it (they could hear someone is
talking to them but can't pick out the words)
central pattern generators Correct Answers networks of
interneurons in the spinal cord and brainstem that coordinate the
interaction of many different motor groups (locomotion,
respiration)
-rhythmic movements
-more complex motor patterns
-reflexes can perform simple elements of movements but not
complex patterns (ie stretch reflexes cannot restore postural
stability after a perturbation, a centrally coordinated response is
required)
-posture and movement are programmed by CPGs
-mainly located in the spinal cord and in brainstem (some also in
the hypothalamus)