Cognitive/Motor Flashcards
Large RFs, spatial features and motion.
Primary visual cortex
Small RFs, simple image features such as oriented line segments.
Parietal visual stream
Large RFs, complex image features
Temporal visual stream
visual and other sensory modalities are combined
Polymodal
Object recognition in the temporal lobe
Faces
The pupillary reflex of light in one eye
both pupils constrict
Frequency
Number of cycles per second = pitch (hertz)
loudness is determined on the wave by
Amplitude
Decibels
sound pressure/reference pressure
Whisper occurs at what dB
0-20
Conversation occurs at what dB
20-40
Heavy Traffic occurs at what dB
40-60
Live Rock occurs at what dB
80-100
Discomfort occurs at what dB
100-120
Pain occurs at what dB
140-160
The three layers on the normal audibility curve
Threshold, damage threshold, and pain
damage threshold
90 dB
How does maximum listening time per day change with volume level?
As volume increases, the listening time significantly decreases
Presbycusis
Progressive, bilateral hearing loss with increasing age, mainly for frequencies > 1,000 Hz
Where basilar membrane motion is converted into neuronal activity
the organ of corti
Deflection of basilar membrane produces
shearing of hair cell stereocelia
Outer hair cell “electromotility”
- Shortens when
- Lengthened when
- Shorten when depolarized
- Lengthened when hyperpolarize
Are used to evaluate hearing in newborns
Otoacoustic emissions
Hair cells contain what type of receptor
Hair cells contain mechanoreceptors
What connects each stereocilia?
Tip links
Tip links
gate ion channels in the stereocilia at the top of the hair cells
Mechano-transduction at tip link activates
activates afferent neurons
Ringing in your ears
Tinnitus
Two types of tinnitus
Transient and Chronic
Transient tinnitus
(< 24 hours)
- Usually due to loud noise.
- Excessive mechanical stress of stereocilia. - Tip-links are thought to break, but
eventually grow back (ringing stops).
Chronic tinnitus
- Many causes, but predominately loud noise. - Origin can be either inner ear, nerve or
central pathways. - Impacts quality of life (does not stop
Visual transduction
Photons: high energy but hard to catch (~100X106 photoreceptors)
Trillions of opsin molecules
Slow: G-protein cascade
Amplification: one photon closes many ion channels
Auditory transduction
Sound waves: low energy but all around (~15,000 hair cells)
Several hundred thousand tip links
Fast: direct channel activation
No amplification of the transduction
Central auditory pathways
Primary auditory cortex Thalamus Midbrain Medulla 8th cranial nerve (vestibular and auditory)
Cochlear Implant is required due to
Hair cell loss due to ageing, loud sounds, ototoxic drugs:
Cochlear Implant steps
1) Implanted through round window
2) Electrode placed in scala tympani
3) Electrodes are spaced along the cochlear spiral to stimulate groups of afferent fibers that respond to different frequencies.
Generally ~12 electrodes.
Why when the head rotates; eyes rotate in opposite direction and gaze does not change
Vestibular ocular reflex
vestibular system controls
includes the parts of the inner ear and brain that process the sensory information involved with controlling balance and eye movements.
One key similarity between the auditory and vestibular system
Tip links gate ion channels in the stereocilia
Organization of semicircular canals at rest vs rotation of the head
stereocilia bend
Utricle and saccule detect
linear acceleration
- Utricle: horizontal
- saccule: vertical
How many taste buds do you have?
about 10000
5 types of taste
Umani, Salty, Sour, Bitter, Sweet
Central taste pathways goes through …..
Cranial Nerves
Medulla
Thalamus
Ipsilatory gustatory cortex
Olfaction
Smell
Salty channels
sodium moving through channel
Sour channels
Sodium and hydrogen move through channel then potassium is pumped back across against hydrogen
Bitter channels
Bitter blocks potassium channels
various G-protein cascades
Sweet channels
G-protein cascade
Umani channels
Glutamate receptors
G protein cascade
Olfactory signal transduction
Ordorant binding to orderant receptor
G protien activation
Opening of ion channel
How many orderant receptors?
1000
Central olfactory pathways
Olfactory bulb to Olfactory tract to nerve to limbic system
Consciousness is measured by
behavior and brain activity
State of consciousness
level of arousal (awake, asleep, etc.)
thoughts, feelings, desires, ideas, etc
Conscious experience
The electroencephalograph (EEG)
Mainly measures activity of neurons located near the scalp in the
gray matter of the cortex.
EEG Frequency
is related to
levels of responsiveness.
EEG amplitude
is related to synchronous neural activity
EEGs reflect
mental states
relaxed with eyes closed
slow frequencies
Alpha rhythm
alert
fast frequencies
Beta rhythm
Awake rhythm amplitude and frequency
Low amplitude and high frequencies
How many stages of NREM
4
NREM
slow wave sleep
REM
paradoxical sleep
As you go from stage 1 to 4 what changes?
amplitude increases
frequency decreases
How long does it take for stages 1-4 of NREM to occur?
30-45 minutes
REM sleep rhythm
low amplitude
high frequencies
Sleep apnea
sudden reduction in respiration
At REM what happens to eye and neck movements
Increased eye movement
Increased inhibition of skeletal muscle (low muscle tone, but twitching can occur)
At REM what happens to the heart and respiration rate?
Increased heart rate and respiration
Regulating States of consciousness involves two parts
Brainstem nuclei that are part of the reticular activating system
- Hypothalamus with circadian and homeostatic centres
what occurs when waking in norepinephrine, serotonin and acetylcholine levels?
increased norepinephrine and serotonin
decreased acetylcholine
State when aminergic neurons are active
waking (reticular activating system)
what occurs to go into REM sleep in norepinephrine, serotonin and acetylcholine levels?
decreased norepinephrine and serotonin
increased acetylcholine
State when cholinergic neurons are active
REM sleep
the reticular activating system is for
Waking or REM sleep
the hypothalamus is for
NREM sleep or waking
What happens to GABA, histamine, and activation of the thalamus and cortex levels during waking?
decreased GABA
increased histamine
increased activation of the thalamus and cortex
increased histamine would result in
waking
Increased inhibition would result in
NREM sleep
What happens to GABA, histamine, and activation of the thalamus and cortex levels for NREM sleep?
increased GABA
decreased histamine
decreased activation of the thalamus and cortex
Motivation
produce goal-directed behavior
Emotions
accompany our conscious experiences
Mesolimbic dopamine pathway
Reward pathway
the primary neurotransmitter in the reward pathway
dopamine
Self stimulation experiments
Continuous activation of reward related areas of the brain.
What pathway involves the Prefrontal cortex, midbrain, locus cereleus in the reticular activating system
Mesolimbic dopamine pathway
Limbic system
Emotions system
Limbic system parts of the brain
Olfactory bulb
Amygdala
Hippocampus
Hippocampus
related to memory
Schizophrenia
diverse set of problems in basic cognitive processing. Wide range of symptoms including hallucinations and delusions. Affects one out of 100 people.
Reducing the effects of dopamine can improve symptoms of
Schizophrenia
decreased activity in the anterior limbic system results in
Depression
increase the levels of serotonin and
norepinephrine in the extracellular space around synapses is a treatments of
depression
Bipolar disorder
swings between mania and depression.
Treatments that include lithium that reduces certain synaptic signalling pathways are for
Bipolar disorder
Central olfactory pathways leads to the ____ system by ____
limbic system by the olfactory bulb/nerve
What does the odorant bind to and where?
odorant receptors in the cilia
What does the odorant binding activate?
G-protien and opens the ion channels
Consolidation
short-term to long-term
Best way for consolidation to occur
sleep
Learning and memory occurs in the
Hippocampus
Conscious experiences that can be put into words
Declarative memory
Memory type: Skilled behaviour
Procedural memory
Short term declarative memory occurs in what parts of the brain?
Hippocampus and other temporal lobe structures.
T/F: Long term declarative memory occurs in many areas of association cortex
T
