Home > Flashcards > Print Preview
The flashcards below were created by user
on FreezingBlue Flashcards. What would you like to do?
Frontal lobe is made up of?
- 1. Prefrontal area
- 2. Motor area
Prefrontal area of the frontal lobe does what?
- -elaborates the thinking process
- -planning of complex movements
Motor area of frontal lobe does what?
- -controls thin muscles of the body (feet, mouth, fingers, eye)
- -coordinates movements
- -controls speech (articulation of words)
Parietal lobe contains what area?
What does the somesthetic are of the parietal lobe control?
-receives sensations, temperature, and pain sensations from the body
Occipital lobe contains what area?
What does the visual area (the occipital lobe) do?
-detects visual signals
What three areas does the temporal lobe contain?
- 1. Auditory area
- 2. Wernicke's area
- 3. Short-term memory area
What does the auditory area (of the temporal lobe) do?
-detects auditory signals
What does Wernicke's area (of the temporal lobe) do?
-interprets the signification of sentences as they are heard and written
What does the short-term memory area (of the temporal lobe) do?
-stores short-term memory (a few sec)
The frontal lobe and parietal lobe are separated by__________?
Affective behaviors are?
feeling and emotion
Cognitive behaviors are?
related to thinking
cutting a hole in the skull to relieve evil spirits
study of bumps on the head
- -spike went through eye and frontal lobe
- -first frontal lobotomy
4 main functions of the nervous system:
- 1. Detect information using sensory receptors
- 2. Recognize significance
- 3. Decide on response
- 4. Execute an action
Describe afferent pathway.
Sensory (afferent) neurons carry information from PNS to CNS (brain and spinal cord)
Describe efferent pathway.
Neurons relay the information from CNS to effector organs (motor pathway) to elicit a response
What are the 2 types of efferent pathways?
- 1. Autonomic Nervous System- controls internal organs
- a. sympathetic system (fright/flight)
- b. parasympathetic system (rest and digest)
- 2. Somatic Motor Division
- a. controls skeletal muscle
What are the reflex pathways made of?
Nerves, which are made of neurons
PNS has how many pairs of nerves?
- -12 cranial nerves (both sensory & motor)
- -31 spinal nerves (mixed as well)
Cranial nerves mneumonic for order 1-12:
Oh, Oh, Oh, To Touch And Feel A Good Vag So Hot.............1-12
Olfactory, Optic, Oculomotor, Trochlear, Trigeminal, Abducens, Facial, Auditory, Glossopharyngeal, Vagus, Spinal accessory, Hypoglossal
Cranial nerves mneumonic for type:
Some Say Marry Money But My Brother Says Bad Business to Marry Money.......
What do the oculomotor, trochlear, and abducens cranial nerves do?
control eye movement
What does the hypoglossal nerve do?
control tongue movement
What does the olfactory nerve do?
What does the optic nerve do?
What does the auditory nerve do?
hearing and balance
What does the trigeminal nerve do?
- -masticatory movements
- -sensitivity of face
What does the facial nerve do?
- -muscles of facial expression
- -taste from anterior 2/3 of tongue
What does the spinal accessory nerve do?
movement of neck muscles and viscera, swallowing
What does the vagus nerve do?
sensitivity and movement of heart, lungs, larynx, GI tract
What does the glossopharyngeal nerve do?
- -movement of pharynx, salivary secretion
- -taste from posterior 1/3 of tongue
What are the 4 main regions of the spinal cord?
- 1. Thoracic
- 2. Lumbar
- 3. Cervical
- 4. Sacral (and coccyx)
area of the skin innervated by the sensory axons of the nerve (root)
collection of muscle fibers innervated by the motor axons of each nerve (root)
T/F: Spinal nerves contain mixed pathways (both efferent and afferent)?
What type of info does the dorsal root of the spinal cord carry to CNS?
What type of info does the ventral root of the spinal cord carry to muscles and glands?
What is the outside of the spinal cord composed of?
White matter made of subcortical nuclei
What matter is on the inside of the spinal cord?
gray matter consisting of sensory and motor nuclei
Gray matter of spinal cord is separated into what 3 sections?
- 1. Dorsal horn
- 2. Ventral horn
- 3. Lateral horn
The Dorsal Horn of contains what type of nuclei?
- -visceral sensory nuclei
- -somatic sensory nuclei
The Ventral Horn contains what type of nuclei?
somatic motor nuclei
The Lateral Horn contains what type of nuclei?
autonomic efferent nuclei
T/F: There can be crosstalk between different horns?
True. Ex: when heart attack occurs, left arm hurts
Why is the white matter white?
Myelination of axons
Ascending tract is:
sensory info from spinal cord going up to the brain
Descending tract is:
info from the brain going down to the spinal cord (carrying command to motor neurons)
What bones protect the CNS?
- 1. Cranium (skull)
- 2. Vertebral column (spine)
layers of membrane that lie b/w the brain tissue and skull
What are the 3 meninges of the brain?
- 1. Dura mater
- 2. Arachnoid mater
- 3. Pia Mater
Dura mater is the ________ layer?
- outside, hard layer
- -closest to skull
Arachnoid mater is the _________ layer?
middle, spidery layer
Pia mater is the __________layer?
- soft, innermost layer
- -covers and adherent to brain
What can be found in the subarachnoid space?
cerebrospinal fluid (CSF)
What are ventricles in the brain for?
provide nourishment (like glucose) and protection
How many ventricles are in the brain? Explain them.
- -lateral 1 and 2
- -intraventricular foramen
- -cerebral aqueduct
- -central canal
What is choroid plexus?
- -secretes CSF
- -made of modified ependymal cells, pia mater and capillaries
Someone w/ abnormally large ventricles in the brain might have...?
The blood-brain barrier....
- prevents toxic substances from entering the brain
- -only lipid solubles can get in (anesthetics, alcohol, gases)
- -proteins cannot get out
- -medulla oblongata does NOT have bbb
- 1. diencephalon
- 2. cerebrum
- 1. midbrain
- 2. pons
- 3. medulla oblongata
- 4. RAS
What is the RAS?
- reticular activating system
- -control of wakefulness
- -filtering of repetitive stimuli
- *a network starting in brainstem and going through midbrain
- 1. conduction pathway w/w higher and lower brain centers
- 2. Two parts-
Tectum aka roof contains:
- 1. Inferior colliculi- auditory
- 2. Superior colliculi- adjust movements of the head and eyes toward a stimulus (visual, somatic and auditory coordination)
- **AUDITORY & VISUAL REFLEX RESPONSE
Tegmentum aka covering contains:
- 1. reticular formation, substantia nigra and red nuclei "rubro" important for movement
- 2. controls motor functions, regulates awareness and attention, and regulates some autonomic functions
- 1. relays info from the cerebrum to the cerebellum
- 2. cooperates w/ the medulla oblongata to control resp. rate and depth
The Medulla Oblongata....
- 1. visceral (gray matter) controlling heart rate, respiration, coughing, vomiting, blood vessel diameter
- 2. white matter containing ascending somatosensory tracts and descending corticospinal tracts
- **Many tracts cross midline at the medulla or spinal cord (DECUSSATE, CONTRALATERAL CONTROL)
- 1. processes info from cerebral motor cortex, proprioceptors, visual and equilibrium pathways
- -important for balance, posture and coordinated movement
The Diencephalon (part of forebrain) contains what 3 sections?
- 1. Thalamus
- 2. Hypothalamus
- 3. Limbic System
The Thalamus is:
- a relay station w/ tons of nuclei
- -memory processing
The Hypothalamus is:
- the center for homeostasis
- -regulation of thirst, reproduction, hunger, temperature, sympathetic NS
The Limbic System is:
- -connects to frontal lobe, temporal lobe, thalamus and hypothalamus
- -mediates emotional responses
- -"basic instincts"
The forebrain consists of what 2 parts?
- 1. diencephalon
- 2. cerebrum
The diencephalon contains what 3 structures?
- 1. Thalamus
- 2. Hypothalamus
- 3. Limbic System
What is the thalamus?
a relay station; memory processing
What structures are found in the Limbic System?
- 2.Cingulate Gyrus
- 4.Insular cortex
anger, fear and aggression
involved in positive and negative emotional response
learning and memory
relates visceral/autonomic sensations of emotion to the rest of the brain
The cerebrum is important because....
- it is the site of higher brain function
- it is the largest part of the brain
The cerebrum has 2 hemispheres, connected at the___?
The outer layer of the cerebrum consists of _____matter, which forms the_____.
- Gray; cerebral cortex
- -6 layers total
Layer 1 cerebral cortex=
has almost no cell bodies so they don't get damaged since they are close to outside
Layer 2 cerebral cortex=
mainly inhibitory interneurons
Layer 3 cerebral cortex=
mainly excitatory interneurons
Layer 4 cerebral cortex=
mostly sensory signals (main input layer)
Layers 1,2,3 of cerebral cortex do what?
connect adjacent cortical regions and integrate cortical function
Pyramidal cells are found in what layer(s) of cerebral cortex?
5 and 6
What are pyramidal cells?
projection neurons (major output cells of the cortex)
What are non-pyramidal cells?
they are involved in local processing in the cerebral cortex
What is the main function of the cerebral cortex?
integrating center for sensory information
What do the sensory cortices do?
receive and perceive sensory input
What are association areas?
- where more complex processing occurs
- -receive information from multiple sensory and motor areas
Skeletal muscle movement gets perveived in what area?
the motor association area which is adjacent to the primary motor cortex
What does the prefrontal association area (in frontal lobe) do?
coordinates info from other association areas and controls some behaviors
sensory info from skin, musculoskeletal system, viscera and taste buds goes to what area(s)?
- -primary somatic sensory cortex
- -sensory association area
- (in parietal lobe)
Where is the insular cortex located?
deep within the lateral sulcus, between the temporal and parietal lobes
Where is the somatosensory cortex located?
parietal lobe right behind the central sulcus
- map showing areas of the somatosensory cortex that are devoted to certain areas of the outside body.
- -size of the region does not match what's on outside of body (lips, hands)
What does the somatosensory cortex detect and perceive?
The larger the somatosensory cortical area, the _______ sensitive the part of the body.
MORE, because there are more neural circuits and innervations
the limited ability of nervous system to alter anatomy and function in response to changes in activity pattern
Which hemisphere is particularly important in the Geschwind Model of Language?
comprehends speech or sentences
plans and sequences response outloud
primary motor cortex:
neural network that connects Wernicke's area to Broca's area
- recognition of a written word
- -people w/ dyslexia have damage here
Primary visual cortex:
reading a word
primary auditory cortex:
perceives sound waves
What area is important for language expression (speaking and writing words)?
What area is important in speech comprehension?
What are the steps is responding to a heard question??
- 1.primary auditory complex
- 2.Wernicke's area
- 3.Arcuate fasciculus
- 4.Broca's area
- 5.Motor cortex
What are the steps in reading aloud??
- 1.Primary visual cortex (occipital lobe)
- 2.angular gyrus- recognize
- 3.Wernicke's area
- 4.Arcuate fasciculus
- 5.Broca's area-plan to speak
- 6.motor cortex- speak
damage or lesion to an area of brain
widespread damage to all areas of left hemisphere
- damage to secondary auditory complex
- -RESULT: fast, fluent, nonsensical jargon, can make up new words (neologism)
- -damage to premotor area
- -difficulty in speech production, but can comprehend good
- -RESULT: nongrammatical, awkward speech
- -RESULT: can use nouns, verbs, but not in-between fillers and conjunctions
- damage to arcuate fasciculus
- -can understand what you hear and produce your own language w/ some difficulty, but CAN'T repeat what someone says/what they hear.
Which hemisphere processes sign language?
- -Broca's: controls physical act of signing
- -Wernicke's: comprehension of signing
Which hemisphere is damaged if someone has trouble carrying out a long conversation or writing a long paper? (extended discourse)
Right side of brain controls left body, vice versa.
2nd order neurons in somatic sensory pathways (always, never, sometimes) cross the midline/deccusate?
1st order neurons cross over where?
- in the dorsal horn of spinal cord before reaching the brain
- -triggered by receptor activation
- -pain, temperature or coarse touch
2nd order neurons cross over where?
- in the spinal cord or medulla
- -fine touch, vibrations, and proprioception
3rd order(tertiary) neurons cross over/synapse where?
- in the thalamus
- -originate and come together in thalamus and ascend up into sensory cortex
Motor ouput crosses over where?
in medulla and spinal cord depending on whether it is ascending or descending message
In the visual field (past the eye), where does decussation occur?
in the optic chiasm
In the eye, where does crossing over occur?
at the nasal retina
The left visual field is processed by the ____hemisphere and the right visual field is processed by the _______hemisphere?
#, type, function
#, type, function
#, type, function
#, type, function
#, type, function
- -sensory and motor (mixed)
- -chewing movements and sensitivity of face
#, type, function
- -motor and sensory
- -muscles of facial expression and taste at front 2/3 of tongue
#, type, function
- -hearing and balance
#, type, function
- -motor and sensory
- -movement of pharynx, salivary secretion, taste at back 1/3 of tongue
#, type, function
- -sensory and motor
- -sensitivity and movement of the heart, GI tract, larynx, and lungs
Spinal accessory nerve
#, type, function
- -movement of neck muscles, swallowing
#, type, function
- -movement of tongue
What are the 2 types of electrical signaling?
- 1. Graded potentials
- 2. Action potentials
Describe a graded potential:
- -the strength of the GP is directly proportional to the strength of the stimulus
- -stimulus will open mechanical or chemical gates on dendrites and cell bodies
- -the more channels that are open, the greater the ion flow
- -the stronger the initial amplitude, the farther the GP will travel along the neuron
Why do GP's lose their strength?
B/c of cytoplasmic resistance (ions leak out)
Describe an action potential:
- If the signal at the axon hillock is above threshold, voltage-gated channels will open and an action potential is generated
- -an action potential depolarizes the axon terminal
- -then voltage-gated Ca channels open, letting Ca into the cell
- -this triggers exocytosis of synaptic vesicle content
- -and a neurotransmitter diffuses across synaptic cleft and binds w/ receptors on post-synaptic cell
When does an EPSP occur (excitatory post synaptic potential)?
when the neurotransmitter causes depolarization of the post synaptic cell
When does an IPSP occur (inhibitory post synaptic potential)?
when the neurotransmitter causes hyperpolarization of the post synaptic cell
What allows the neuron to react to stimuli of different strength and duration?
the frequency of AP propagation= more of less ion flow=longer of shorter cell is above threshold= greater or lesser # of APs generated
If a cell is hyperpolarized, is it more/less likely to fire an action potential?
What is temporal summation?
- when 2 GPs arrive from the same place close together in time
- -if far apart in time, 2 GPs will not create an AP
What is spatial summation?
- when 2 or more pre-synaptic neurons act at the same time on a single post-synaptic cell
- -BUT can have inhibition of AP if there are 2 excitatory neurons and 1 inhibitory
What is convergence?
multiple signals acting on the same source/cell
What is axoaxonic modulation?
- -PRE-synaptic modulation
- -may affect only a few post-synaptic cells
- -inhibition or excitation happens at one collatoral axon site after action potential has been generated
- -pre-synaptic inhibition=if there is a decrease in neurotransmitter release from pre-synaptic cell
- -pre-synaptic facilitation=if there is an increase in neurotransmitter(keeping Ca channels open)
What is axosomatic/axodendritic modulation?
- -POST-synaptic modulation
- -pre-synaptic neuron acting at the cell body (soma) or dendrites(dendritic) of post-synaptic neuron
- -occurs before an AP has been generated, so it either creates an AP for all target cells or not one at all
- -affects all post-synaptic cells!
- -all (EPSP) or none (IPSP) are affected
- -no neurotransmitter released= no response in target cells (if there is a both an excitatory and inhibitory neuron firing at the same time)
- -general anesthesia
- specialized neuronal structures that detect specific types of energy
the energy form of a stimulus
The law of specific nerve energies states that:
- sensory receptors are specific for a particulat modality
- --receptors in your eyes are specific for vision
What are the 5 groups of receptors?
- 1. Chemoreceptors
- 2. Mechanoreceptors
- 3. Photoreceptors
- 4. Thermoreceptors
- 5. Nociceptors
What are the 3 types of neural receptors?
- 1. Simple receptors- neurons w/ free nerve endings
- 2. Complex neural receptors- have nerve endings enclosed in connective tissue capsules
- 3. Special sense receptors- cells that release neurotransmitter onto sensory neurons initiating an AP.
Define adaptation in reference to sensory receptors.
process in which sensory receptors decrease their response to a stimulus over time
What is a tonic receptor?
- -adapts slowly, transmits signals to the CNS as long as the stimulus persists
- -blood pressure
What is a phasic receptor?
- -fires when the first stimulus is received, then switches off when the stimulus is at a constant intensity
- -used for non-threatening situations
- -smell of perfume, wearing a watch, wedding ring
What are the two parts of the outer layer of the eye?
What is the sclera?
connective tissue in eye
What is the cornea?
transparent part of eye, allows light to enter
What are the 5 parts of the middle layer of the eye?
- 1. choroid
- 2. ciliary body
- 3. lens
- 4. iris
- 5. pupil
What are the 3 part of the inner layer of the eye?
- 1. retina
- 2. fovea
- 3. optic disk
What is the choroid?
absorbs light, contains melanin, brownish
What is the ciliary body?
attaches the lens, it is continuous w/ the choroid, helps shape the lens
What is the lens?
it helps focus light on the retina
What is the iris?
pigmented smooth muscle that controls the amount of light allowed in
What is the pupil?
hole in iris
What is the retina?
CNS neural tissue, contains rods (monochromatic) and cones (color)
What is the fovea?
area of greatest visual acuity, where cones reside
What is the optic disk?
- blind spot
- -no photoreceptors
- -where blood vessels and nerves enter eye
What are the 3 layers that make up the retina?
- Starting closest to light
- 1. Inner layer= Ganglion cells (generate APs)
- 2. Middle layer= Bipolar cells
- 3. Outer layer= Photoreceptors (rods + cones)
What is the macula lutea?
a depression in the center of the retina that is created by the bipolar and ganglion cells being displaced laterally.
T/F: The fovea contains rods and cones.
False, only cones!
T/F: The retina contains rods and cones.
Which of the two (rods or cones) need more light?
As you move away from the fovea, the ratio of rods to cones____________?
increases, because the fovea contains mostly cones
What are disks?
- located in the outer segment of rods and cones, they are molecules that absorb light
- -contain photopigments retinal and opsin
- -also contain the Gprotein transducin and the enzyme phosphodiesterase (PDE)
In darkness, cGMP levels are_____? Are Na+ channels open or closed?
In darkness, what enters the cells and what state are the cells at?
In darkness, what channels open in the inner segment in response to depolarization?
In darkness, Ca++ channels opening allows the release of what neurotransmitter?
GLUTAMATE, which communicates w/ bipolar cells
In light, what absorbs one light photon and dissociates from opsin?
In light, retinal dissociating from opsin leaves behind what?
a bleached opsin (less sensitive to light)
In light, bleached opsin activates what G protein?
In light, transducin activates?
In light, PDE breaks down?
cGMP, which closes Na+ channels!
Decreased cGMP in a cell leads to?
closing of Na+ channels
Closing of Na+ channels does what to the cell?
HYPERPOLARIZES it because potassium is leaving the cell
The secretion of glutamate ________ when Na+ and Ca++ channels close?
When is there a tonic release of neurotransmitters in respect to vision?
in the dark
With respect to vision, when is the release of neurotransmitters reduced?
Frequency is directly proportional to?
What is frequency measured in?
What range of Hz can we hear?
What is amplitude measured in?
What does amplitude help us determine?
whether a sound is loud or quiet
What is the duration of a sound?
how long or short the sound wave is
What structures make up the outer ear?
- Ear canal
- Tympanic Membrane
What structures make up the middle ear?
- Oval window
- Round window
What structures make up the inner ear?
- semicircular canals
- oval window
- eustachian tube
- cochlear duct
- tympanic duct
- vestibular duct
- cochlear nerve
- cochlea w/ helicotrema
How is sound transduced?
- sound hits tympanic membrane
- vibration energy hits 3 bones in middle ear which then vibrate
- The oval window is attached to the stapes so then it vibrates
- Fluid waves start in cochlea
- Waves push on membranes of the cochlear duct
- Energy transmits across cochlear duct into the tympanic duct and dissipates back to the middle ear via the round window
- Hair cells in the cochlear duct create APs in the sensory neurons of the cochlear nerve
Where on the basilar membrane are high frequency sounds detected?
near the oval window (closest to outer ear)
Where on the basilar membrane are low frequency sounds detected?
near the helicotrema (inner ear)
What 5 structures make up the vestibular apparatus in the ear?
- Three membranous semicircular canals
- 1. anterior canal
- 2. posterior canal
- 3. lateral canal
- Two saclike swellings
- 1. utricle
- 2. saccule
Where is the vestibular apparatus found?
in the bony labyrinth (cavities in the temporal bones)
What kind of info do the semicircular canals detect?
What kind of acceleration does the anterior canal (of vest. app) detect?
up and down (YES)
What kind of acceleration does the lateral canal detect?
side to side (NO)
What kind of acceleration does the posterior canal detect?
ear toward each shoulder
What does the utricle do?
detects forward and backwards linear acceleration
What does the saccule do?
detects up and down linear acceleration
What is the difference in the type of acceleration that the swellings detect compared to the type of acceleration that the semicircular canals detect?
- canals= rotational
- swellings= linear
What is Associative learning?
making connections between 2 or more stimuli
What is non-Associative learning?
repetition of a stimulus
What is declarative memory?
memory of events that can be put into words (recalling someone's bday)
What is procedural memory?
memory of how to do things (ride a bike)
What part of the brain is involved in short term declarative memory?
What part of the brain is involved in short term procedural memory?
basal ganglia (specifically the striatum)
What party of the brain is involved in the long term procedural memory?
- basal nuclei
- premotor cortex
What part of the brain is involved in long term declarative memory?
the association cortex
What is retrograde amnesia?
- cannot recall events that have happened before a lesion/accident/disturbance in brain
- can still form new memories
What is anterograde amnesia?
- cannot recall events that have happened after a disturbance in the brain/accident/lesion
- can still remember what happened before the accident
What is transient global amnesia?
temporary memory loss due to lack of oxygen, blood or brief cerebral ischemia
What would happen if you damaged the medial temporal lobe?
- anterograde amnesia
- can't store and retain procedural memories
- can't store declarative memories
What would happen if you damaged the medial dorsal thalamus?
similar to anterograde amnesia just milder memory deficits
What is Korsakoff's syndrome?
- a deficiency in vitamin B1 (thiamin)
- due to chronic alcoholism
- results in damage to the medial temporal lobe and thalamus
- profound anterograde amnesia
- unaware of memory loss
- loss of declarative and procedural memory
Why is the hippocampus important for memory formation?
- not the site of memory storage BUT
- important for laying down of relational memories, spatial memories, declarative memories
Where does memory storage occur?
in the association areas of the frontal and temporal lobes
List the stages of Alzheimer's disease:
- Stage 1: anterograde amnesia, careless, disoriented
- Stage 2: loses memory of all recent events
- Stage 3: loss of semantic (understanding of words) and procedural memory too
What does Alzheimer's disease look like in the brain?
- can find neurofibrillary tangles in the cells due to hyperphosphorylation of Tau
- plaques found extracellularly
- amyloid beta protein
- huge holes in brain tissue
- thalamus and hippocampus take a hit and shrink in size drastically
- cholinergic neurons in the forebrain degenerate
What is LTP (long term potentiation)?
- an experience increases the functioning of the hippocampal neurons
- results in an increased neural responsivity
- results in increased amplitude and duration of EPSPs
- effect can last for weeks (long term)
Long term potentiation mechanism-->at rest, not learning anything new
- low to moderate release of glutamate
- glutamate binds to AMPA receptor which opens sodium channels=depolarization
- glutamate binds to NMDA receptor which opens calcium channels, but channels are blocked by Magnesium ions
- EPSP may or may not reach threshold
Long term potentiation mechanism--> when learning a new task/new memory
- more glutamate released
- more sodium channels open
- greater depolarization state repels Magnesium ions and allows calcium entry
- results in secondary messenger activation of Protein Kinase 1 and 2
- AMPA/sodium channels stay open longer
- release of paracrine PK2 which acts back on presynaptic cell to release more glutamate
- autocrine action of PK1
What is a polysomnograph?
- EOG + EEG + EMG
- electrooculograph (eye movement)
- electromyograph (muscle tone)
- electroencephalograph (voltage generated by excitation of dendrites of pyramidal cells in cortex)
List the 5 stages of sleep:
- 1 NonREM: relaxation, falling asleep
- 2 NonREM: light sleep
- 3 NonREM: deep sleep
- 4 NonREM: deep sleep
- 5 REM: lots of dreaming, rapid eye movement
What is the ultradian rhythm?
the regular occurrence of REM and nonREM sleep in cycles of less than 24 hours
What is the circadian rhythm?
- our 24 hour cycle of sleep and wakefulness
- controlled by the SCN
- correlated with body temp
What happens with partial sleep deprivation?
- weight loss
- increase in cortisol (stress hormone)
- decrease in insulin sensitivity
- decrease growth hormone
- decreased appetite
- decrease in leptin
- increase in ghrelin
- mania occassionally
What happens in total sleep deprivation?
- death (in rats)
- immune problems
- memory loss
T/F: during REM sleep our brain metabolic rate increases
Where are the neurons (sleep-OFF neurons) located that are involved in wakefulness?
the posterior lateral hypothalamus
Where are the sleep-ON neurons located that are involved in sleep onset?
ventrolateral preoptic area of the anterior hypothalamus (VLPO)
What structure is responsible for arousal?
- RAS (reticular activating system)
What are the 2 phases of REM sleep?
When are norepinephrine levels the highest?
When are serotonin (5HT) levels highest?
When are acetylcholine (ACh) levels highest?
during wake and REM equally high
When are hypocretin/orexin levels highest?
Which neurotransmitters are completely inactive during all stages of sleep (slow wave and REM)?
When are dopamine levels the highest?
Which neurotransmitters are lightly released during SWS?
- 5HT (serotonin)
Which neurotransmitters are lightly released during REM sleep?
T/F: As you fall asleep, activity in the RAS increases.
Why should you not take sleeping pills?
they all suppress REM sleep so you may sleep well during the first night but then you will have REM rebound