EXAM 2 Flashcards by Maddie Lefkowitz

____ between forms of energy and intensity/different forms of stimulation
ex) somatosensory system-we can distinguish different forms types of touch bc our skin contains a variety of receptors and users some lines to signal light touch, vibrations, and stretching

Discrimination between stimuli

How well did you know this?

Not at all

Perfectly

-we can distinguish different forms types of touch bc our skin contains a variety of receptors and users some lines to signal light touch, vibrations, and stretching
–free nerve endings - pain, temperature
–Merke;’s disc - touch
–Meissner’s corpuscle-touch
–Pacinian corpuscle - vibration and pressure
–Ruffini’s ending -stretch

Somatosensory discrimination between stimuli

How well did you know this?

Not at all

Perfectly

1) sensory receptor
2) transduction process
3)neural pathway from receptor to cortex
4) coding

Pathway to perception

How well did you know this?

Not at all

Perfectly

specialized device for picking up information from external world

sensory receptor

How well did you know this?

Not at all

Perfectly

receptors turn energies (light waves, pressure, sound waves, etc) into graded potentials and action potentials

transduction process

How well did you know this?

Not at all

Perfectly

brain (often cortex) interprets action potential and “perceives” input

coding

How well did you know this?

Not at all

Perfectly

-Pacinian corpuscles -vibration/pressure
-mechanical opening of channels in transduction
–“stretch-gated” channels in dendrites
-transduction-mechanical stimulation of receptor any stretch
—coding for intensity of pressure on skin. temporal coding by different neurons, frequency of neural impulses
—-thalamus is main relay station to cortex

Example Pathway to Perception of Pressure

How well did you know this?

Not at all

Perfectly

organized alternating between L and R
-comes from overlap of visual fields between eyes at center but little overlap in periphery
–tuned up for input from each ease in columns, with more NT transfer for each

ocular dominance columns

How well did you know this?

Not at all

Perfectly

vision “without knowledge”
-modality specific-restricted to vision
-not a memory disorder
-items can be recognized with other modalities, but not with vision

visual agnosia

How well did you know this?

Not at all

Perfectly

inability to recognize faces
-fusiform area in temporal lobe large specific to faces is damaged
-can distinguish between faces and objects but difficulty in distinguishing between faces
-lack of facial identification

Prosopagnosia

How well did you know this?

Not at all

Perfectly

tympanic canal, 1 of 3 principle canals running along length of cochlea

scala tympani

How well did you know this?

Not at all

Perfectly

an electrochemical devise that detects sounds and selectively stimulates nerves in different regions of cochlea via surgically implanted electrodes

cochlear implant

How well did you know this?

Not at all

Perfectly

-used to find mate and appropriate food and to flee predators
-smell and taste are closely related (smell counts for at least 75% of taste/distinguishability)
-smell and memory are intertwined bc of the amygdala hippocampus are part of the olfactory pathway

Functions of Smell

How well did you know this?

Not at all

Perfectly

1) odors are complex chemicals that attach to multiple receptors–similar chemicals attach to similar receptors
2) all receptors of one type synapse onto same glomeruli in olfactory bulb
3)a combinational map of activated glomeruli is produced in bulb
4) bulb projections are mapped onto cortical areas

Coding and Perception of Odor

How well did you know this?

Not at all

Perfectly

a hormone secreted by pineal gland used as a marker of circadian rhythmicity in humans

*SCN takes info on day length from retina, interprets it, and passes it to pineal gland, which secretes this hormone in response two message
-a couple hours prior to sleep, secretions rise but is inhibited by daylight
–released cyclically in absence of light cues
–if SCN is destroyed, circadian rhythms disappear
-thought o play a role in photoperiodism in seasonal breeding animals
-SCN is known to have hormone receptors so there may be a loop from pineal back to SCN

melatonin

How well did you know this?

Not at all

Perfectly

self-sustained, generated within an organism

endogenous

How well did you know this?

Not at all

Perfectly

a pattern of EEG activity comprising a mix of many different high frequencies with low amplitude

desynchronized EEG/aka beta activity

How well did you know this?

Not at all

Perfectly

an inherited disease that causes people in middle age to stop sleeping, which, after a few months, results in death

fatal familial insomnia (FFI)

How well did you know this?

Not at all

Perfectly

sleepwalking

somnambulism

How well did you know this?

Not at all

Perfectly

1) sleep is complex, fundamentally different from waking, but just as active
2) one period of sleep is by rapid eye movements (REM), total body paralysis, and small amplitude, high frequency brain waves
-this period is time who most dreams occur
-provided a marker for dreaming so that dreams could then be studied
3)these findings suggested that sleep physiology was an important discipline and suggested that sleep disorders may actually be brain disorders

sleep insights from electrophysiology studies

How well did you know this?

Not at all

Perfectly

the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
-input about physical world into our sensory receptors
-ACTUAL STIMULUS
-occurs when receptors for sensory systems register energy from external environment

Sensation

How well did you know this?

Not at all

Perfectly

the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
-process by which brain selects, organizes, and interprets sensation
-INTERPRETATION
-coding of neural input leads to interpretation of conscious experience by CNS
-can occur without sensation

Perception

How well did you know this?

Not at all

Perfectly

the concept that each nerve input to brain reports only a particular type of info
-particular neurons are, from the outset, labelled for distinctive sensory experiences
-same physiological process by action potentials, with interpretation dependent on which labelled line
-law of specific nerve energies
-sensory pathways linked to perception in that system

labelled lines

How well did you know this?

Not at all

Perfectly

condition in which stimuli in 1 modality evoke the involuntary experience of an additional perception in another modality
-crossing modal sensations in some individuals
-sensation MUST be reproducible within an individual, such that, as an example, a given sound or word always leads to perception of the same color
-fMRI shows abnormal activation in different sensory systems
ex-seeing evokes taste, odors evoke colors, etc
–artificially employed when a devise turns one sense into another (ex-vOICe)

synesthesia

How well did you know this?

Not at all

Perfectly

neuron upon which information from more than one sensory system converges

polymodal neuron

-established field of psychology in US -wrote "Principles of Psychology" -first to distinguish sensation and perception and explored understanding of consciousness

William James

experiencing of part of labelled lines pathway that is still there but is projected as if it continues -perception of nonexistent stimuli

phantom limb pain

-reflect constraints developed by sensory systems thru evolution -allow us to experience world as a constant despite bodily movement -can have perception without sensation -one sensation can lead to multiple perceptions, requiring interpretation of sensation, one percept at a time

illusions

mimics what cones would do--produce electrical signals from photons--for interpretation as color

retinal implant

-follows basis of labelled lines -deafness from death of hair cells in cochlea. -device that transforms inputs into AP like hair cells would -works in labelled lines by stimulating afferent neurons -can hear sounds immediately after implant but can't perceive words vs. birds singing --over time, individual will slowly begin to understand meaning of sound

Cochlear implant

1) is learned by association 2)Disorder of development-differentiation causes labelled lines in babies; missing here 3) crossing of labelled line (fMRI)

Synesthesia theories

static image based on water concentration

MRI

real time observation due to blood oxygen level dependent contrast imaging -indirect measure of neural activity via blood flow

fMRI

-primary somatosensory cortex on parietal lobe -size correlates to sensitivity -plasticity in system, more use increases size on map

Somatotopic Map

passive adjustment to stimulus over time' -"getting used to" -decreases response of receptor -shorter duration -involuntary -way in which sensory systems can adapt best to change and suppress extraneous info

adaptation

active adjustment to stimulus -act of learning -often from practice/repeated exposure -decrease in response of receptor due to repeated stimulation that is not meaningful -long lasting -way in which sensory systems can adapt best to change and suppress extraneous info

habituation

use of different labelled lines in one modality to simultaneously understand several aspects of stimulus ex-temperature and pain

parallel processing

retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond -most abundant in periphery of retina (120mil/retina) -responds well tot dim light

rods

retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations. -most abundant in and around fovea (~6mil/retina) -essential for color vision -more useful in bright light -"tuned" to be sensitive to one of 3 Dif wavelengths of light (red, blue, green) -light-dependent, don't respond well to dimness

cones

rods and cones at back of retina -point TOWARD retina rather than toward light -synapse onto bipolar cells, which synapse onto ganglion cells --have long axons make up optic nerve, which crosses at optic chiasma and makes synapses in thalamus

visual system receptors and pathway

1) light alters conformation of chemicals -causes rhodopsin to dissociate from opsin 2) leads to closing of Na+ channels -activated opsin works via G-protein to close Na+ channels 3)leads to IPSPs -hyperpolarizing receptor potentials via closing of Na+ channels *No APs in rods, cones, or retinal bipolar cells, instead decreasing inhibitory NT released to bipolar cells from photoreceptors. THIS leads to depolarization, which increases excitatory NT release to ganglion cells toward brain, triggering AP

How does transduction occur in rods and cones?

-half of axons cross over to other side -from EACH eye, R visual field processed in L hemisphere and vice versa

Optic Chiasma

sent along optic nerve and diverging at optic chiasma -sent to lateral geniculate nucleus in thalamus by optic nerve, which sends info to primary visual cortex -sent superior colliculi and suprachiasmatic nucleus from ganglion cells

Locations to which visual information is sent

a place in the thalamus that receives impulses from the optic nerve -where optic nerve makes ONLY synapse, sending info to primary visual cortex

lateral geniculate nucleus (LGN)

contain photopigment melanopsin, which is mainly sensitive to blue light (short wavelengths)

intrinsically photosensitive retinal ganglion cells (ipRGCs)

-for a location-first done via retinotopic representation of visual field in visual cortex, with info primarily from fovea -we build form from retina to cortex in hierarchical fashion, leading to loss of detail if not in direct path overrepresented by fovea -occipitoparietal lobe = decodes where something is -posterior temporal lobe = decodes what something is

visual coding

-info primarily from fovea, with focus on center, not periphery -shows that central 10% of visual field occupies 50% of map *magnification of foveal representation and compression of periphery -maps onto retina, thalamus and cortex -we build form from retina to cortex in hierarchical fashion, leading to loss of detail if not in direct path overrepresented by fovea

retinotopic map

stimuli in real world that cause neural firing changes in sensory pathway cells --in retina and LGN, simple spots of light --in visual cortex, more complex stimuli -2 types of receptive fields in ganglion cells, responding best to spots (magnocellular and parvocellular)

receptive fields

one of two types of receptive fields in ganglion cells -in LGN in thalamus -inner 2 layers -"spot detectors" -large receptive fields -movement sensitive -all over retina - lots of convergence

Magnocellular Layers

one of two types of receptive fields in ganglion cells -in LGN in thalamus -"spot detectors" -small receptive field -color vision/detail sensitive -lots in fovea-little convergence

Parvocellular layers

1) information from retina leads to several areas of brain that eventually lead to conscious perception of visual scene, as well as unconscious process 2) pathway to primary visual cortex allows for perception of color differences, orientation/form, motion (parallel processing ) 3) parallel processing in different categories of info continues in other regions of cortex -ex-temporal = object/face recognition -ex-parietal = motion, where is object

Visual Sensation to Perception

discovered that neurons in primary visual cortex (PVC) respond selectively to oriented edges -used semi-anesthetized cats and showed object on screen and recorded from PVC cells --bar of light is retinal ganglion cells synapsing onto thalamus cells then onto single cortical cell to perceive bar image -discovered PVC is vast array of hypercolumns

Hube and Wiesel

-according to Huge and Wiesel, it is a vast arrays of hyper columns -chunks of tissue from cortical surface to deep within brain -compulsive organization by orientation in plane, responding to adjacent orientations -includes ocular dominance columns

primary visual cortex

cortex is composed of repeating units (modules) that contain all neuronal machinery necessary to analyze a small region of visual space for a variety of different stimulus attribtues

visual system modular arrangement

measure of sound intensity, perceived as loudness

decibel (dB)

cycles per second, as an auditory stimulus -measure of frequency

hertz (Hz)

conversion of one form of energy into another

transduction

tone with a single frequency of vibration

pure tone

-force that sound exerts peer unit area, which we experience as loudness

amplitude AKA intensity

of cycles per second in a sound wave, measured in Hz -perceived as pitch

frequency

predominant frequency of an auditory tone

fundamental

multiple of a particular frequency called the fundamental

harmonic

characteristic sound quality of a musical instrument, as determined by the relative intensities of its various harmonies -characterized by complex sound waves

timbre

external part of ear

pinna

-the tube leading from the pinna to the tympanic membrane

ear canal aka auditory canal

cochlea and vestibular apparatus

inner ear

cavity between tympanic membrane and cochlea

middle ear

-partition between external ear and middle ear -vibrates in sympathy with sound waves, moving series of tiny bones in middle ear (ossicles)

tympanic membrane AKA-eardrum

3 small bones (incus, malleus, and stapes) that transmit vibration across middle ear, from the tympanic membrane to oval window -carry vibrations to cochlea

ossicles

opening from middle ear to inner ear

oval window

snail-shaped structure in inner ear canal that contains primary receptor cells for hearing -fluid filled tube in inner ear -coding for pitch and intensity begins here

cochlea

AKA vestibular canal 1 or 3 principal canals running along length or cochlea

scala vestibuli

AKA middle canal -central of 3 spiraling canals inside cochlea situated between vestibular and tympanic canals

scala media

structure in inner ear that lies on basilar membrane of cochlea and contains hair cells and terminations of auditory nerve

organ of Corti

one of the receptor cells for hearing in the cochlea, named for the stereocillia that protrude from the top of the cell and transduce vibrational energy in the cochlea into neural activity -do not get born throughout life

hair cell

a membrane in cochlea that contains principal structures involved in auditory transduction

basilar membrane

1 of 2 types of receptor cells for hearing in cochlea -compared with OHC, these are positioned closer to central axis of coiled cochlea

inner hair cell (IHC)

1 of 2 types of receptors for hearing in the cochlea -compared to IHC, these are positioned farther from central axis of coiled cochlea

outer hair cell (OHC)

cranial nerve VIII, which runs from cochlea to brainstem auditory nuclei

vestibulocochlear nerve

brainstem nuclei that receive input from auditory hair cells and send output to superior olivary nuclei

cochlear nuclei

brainstem nuclei that receive input from both right and left cochlear nuclei and provide the first binaural analysis of auditory information

superior olivary nuclei

paired gray matter structures of dorsal midbrain that processes auditory information

inferior colluculi

either of 2 nuclei--L and R-- in the thalamus that receive input from inferior colliculi and send output to auditory cortex

medial geniculate nucleus

organization of auditory neurons according to an orderly map of stimulus frequency, from low to high -mapping of frequency is maintained throughout neural pathway such that, in auditory cortex, a cell that responds to one frequency will be right next to a cell that responds to a freq that is slightly higher or lower than freq it responds to best

tonotopic organization

-cortical region, located on superior surface of temporal lobe, that processes complex sounds transmitted from lower auditory pathways

primary auditory cortex AKA A1

theory that the pitch of a sound is determined by the location of activated hair cells along length of basilar membrane -info about particular freq of an incoming sound wave is coded by which segment fo basilar membrane vibrates in response to that freq --> apex codes for low freq and outer edge of snail shell codes for high freq due to varying stiffness of basilar membrane at these locations

place coding theory

theory that pitch of sound is determined by rates of firing of auditory neurons

temporal coding theory

perceived different in loudness between the 2 ears, which the nervous system can use to localize a sound source

Interaural Intensity Difference (IID)

difference between 2 are in time of arrival of a sound, which the nervous system can use to localize a sound source -occurs by comparing the arrival time of sounds from left and right ears -> if sound comes from directly in front of you or behind you, it will arrive in cortex at same time but sound arrives at DIFFERENT times if coming from left or right

interaural temporal difference (ITD)

process by which the hills and valleys of the external ear alter the amplitude of some but not all frequencies in a sound

spectral filtering

a disorder characterized by the inability to discern tunes accurately or to sing

amusia

decreased sensitivity to sound, in varying degrees

hearing loss

hearing loss so profound that speech perception is lost

deafness

hearing impairment in which ears fail to convert sound vibrations in air into waves of fluid in cochlea -associated with defects of external ear or middle ear

conduction deafness

a hearing impairment most often caused by permanent damage or destruction of hair cells or by interruption of vestibulocochlear nerve that carries auditory information to brain

sensorineural deafness

sensation of noises one hears not caused by external sound

tinnitus

form of central deafness that is characterized by specific inability to hear words, although other sounds can be detected

word deafness

form of central deafness, caused by damage to both sides of the auditory cortex, that is characterized by difficulty in recognizing all complex sounds, whether verbal or nonverbal

cortical deafness

sensory system that detects balance -consists of several small inner ear structure that adjoin cochlea

vestibular system

any one of 3 fluid filled tubes in inner ear that are part of vestibular system -each tube, which are at right angles to each other, detect angular acceleration in particular direction

semicircular canal

enlarged region of each semicircular canal that contains receptor cells (hair cells) of vestibular system

ampulla

brainstem nuclei that receive information from vestibular organs through cranial nerve VIII (vestibulocochlear nerve)

vestibular nuclei

experience of nausea brought on by unnatural passive movement (ex-car, boat)

motion sickness

sensation of smell

odor

sensory system detecting smell -act of smelling -only sensory system that makes a direct connection from olfactory nerve to cortex (PC-piriform cortex and OFC-orbital frontal cortex --makes connection with amygdala and hippocampus prior to thalamus

olfaction

sheet of cells, including olfactory receptors that lines dorsal portion of nasal cavities and adjacent regions

olfactory epithelium

anterior projection of brain that terminates in upper nasal passages and, through small openings in skull, provides receptors for smell

olfactory bulb

complex arbor of dendrites from a group of olfactory cells -all receptors of particular type send axons/synapse to same mitral cells

glomerulus

chemical signal that is released outside body of animal and affect other members of same species

pheromone

specialized system that detects pheromones and transmits info to brain

vomeronasal system

collection of specialized receptor cells, near to but separate from olfactory epithelium, taught detect pheromones and send electoral signals to accessory olfactory bulb in brain

vomeronasal organ (VNO)

any one of a family of probably pheromone receptors produced by neurons in the main olfactory epithelium

trace amine-associated receptor (TAAR)

single relocation of a body part, usually resulting from a brief muscle contraction -less complex than act -end point of a series of hierarchical commands

movement

simple, highly stereotyped and unlearned response to a particular stimulus -few muscle groups involved -highly stereotyped -graded with stimulus -brain not needed, even occurs in paraplegics ex-eye blink in response to a puff of air, cough, knee jerk

reflex

complex behavior, as distinct from a simple movement

act

-plan for a series of muscular contractions, established in nervous system prior to its execution

motor plan AKA motor program

electrical recording of muscle activity

electromyography (EMG)

muscle that counteracts the effect of another muscle

antagonist

muscle that acts together with another muscle

synergist

-neuron that transmits neural messages to muscles/glands -synapse on muscles at neuromuscular junction, releasing acetylcholine, thus activating muscle fibers --Na+ and Ca2+ are major players

motor neuron

region where motor neuron terminal meets its target muscle fiber -point where nerve transmits message to muscle fiber

neuromuscular junction

neurotransmitter (NT) that is produced and released by autonomic nervous system, by motor neurons, and by neurons throughout brain

acetylcholine (Ach)

motor neurons of brain and spinal cord, so called bc they receive and integrate all motor signals form brain to direct movement

final common pathway

body sense -information about position and movements of body

proprioception

muscle receptor that lies parallel to a muscle and sends impulses to central nervous system when muscle is stressed

muscle spindle

any of the call muscle fibers that lie within each muscle spindle

intrafusal fiber

type of receptor found within tendons that sends impulses to CNS when muscle contracts

Golgi tendon organ (GTO)

contraction of muscle in response to stretch of muscle

stretch reflex

-motor system that includes neurons within cerebral cortex and their axons which form the pyramidal tract

pyramidal system AKA corticospinal system

motor system that includes the basal ganglion and some closely related brainstem structures -axons of this system pass into spinal cord outside pyramids of the medulla -looping system of modulation between basal ganglia, thalamus, and cerebellum -doesnt send info to muscles directly -runs outside pyramidal tract and generally involved in fine tuning

extrapyramidal system

apparent executive region for the initiation of movement -strip of tissue in frontal lobe -somatotopically mapped based (think homunculus) -primarily the precentral gyrus -"Go center" -specifies details of movement ~30% of neurons are muscle selective ~50% of neutrons are directionally specific

primary motor cortex (M1)

strip of frontal cortex, just in front of the central sulcus, that is crucial for motor control

precentral gyrus

frontal lobe regions adjacent to the primary motor cortex that contribute to motor and modulate the activity of primary motor cortex

non primary motor cortex

region of non primary motor cortex that receives input from the basal ganglia and modulates the activity of the primary motor cortex programming for execution of complex movement -neurons active when exciting or thinking about executing complex movement that are internally generated -lesions lead to inability to perform complex movement but not simple movement -instructs primary motor cortex for movement

supplementary motor area (SMA) AKA supplementary motor cortex (SMC)

region of nonprimary motor cortex just anterior of primary motor cortex -planning and anticipation of movement -neurons active BEFORE movement -lesions of PMC lead to inability to organize movements in response to sentry cue -instructs primary motor cortex for movement

premotor cortex

paralysis; loss of ability to move

plegia

muscular weakness, often the result of damage to motor cortex

paresis

an impairment in the ability to carry out complex movements, event hough there is no muscle paralysis

apraxia

neuron that is active both when an individual makes a particular movement and when that individual sees another individual make the same movement -discovered in premotor cortex in 2004 -don't work if never done task Disproved theories: those that link them to babies learning, language learning, empathy, sports fans, and failure of mirror neurons causing autism

mirror neuron

group of forebrain nuclei, including caudate nucleus, globulus pallidus, and putamen, found deep within cerebral hemispheres -> initiation, amplitude/direction, habits

basal ganglia

structure located at back of brain, dorsal to pops, that is involved in central regulation of movement and in some forms of learning ~10% of brain mass but contains half of all neurons -sensory input into brain allows sensory correction of motor inputs -feedback control of movement -motor learning -timing and coordination of complex movement -how drunkenness is tested, as its the first region impaired by alcohol

cerebellum

loss of movement coordination, often caused by disease of cerebellum

ataxia

difficulty of movement in which gestures are broken up into individual segments instead of being executed smoothly -symptom of cerebellar lesions

decomposition of movement

degenerative neurological disorder, characterized by tremors at rest, muscular rigidity, and reduction in voluntary movement, caused by loss of dopaminergic neurons of substantia nigra -characterized by damage of basal ganglia

Parkinson's Disease

brainstem structure that is a major source of dopaminergic projections to basal ganglia

substantia nigra

genetic disorder, with onset in middle age, in which destruction of basal ganglia results in a syndrome of abrupt, involuntary writhing movements and changes in mental functioning

Huntington's Disease

form of energy made when air molecules vibrate and move in pattern called waves

sound

collected in OUTER EAR waves amplified in MIDDLE EAR INNER EAR transforms vibrations into graded potentials and then AP -movement of fluid inside cochlea tilts cilia

movement of sound waves in ear

bristle like projects extending from hair cells -movement stimulates nerves, which send signals to brain, which, in turn, process signals into sounds we hear -tiny bristle that protrudes from hair cell in auditory or vestibular system -tips joined by fiber link -can be regrown by hair cells IF not badly damaged

(stereo)cilia

-vibration -> graded potential occurs in cilia of hair cells by mechanical changes, which open K+ and Ca2+ channels (mechanically-gated) --DEPOLARIZE hair cell and cause graded (generator) potential BUT hair cells are NOT neurons and do not fire AP --GP causes release of glutamate at synapse with auditory nerve --if sufficient stimulation occurs to reach threshold at axon hillock/auditory nerve, AP will fire

Auditory Transduction

-hair cells can grow new cilia IF they are not badly damaged BUT hair cells do not get born throughout life -> after a year of daily exposure to 20+ min/day of v. loud sound, most humans become partially deaf --short term damage is reversible, but it becomes irreversible w/ chronic exposure --repeated exposure to sounds of 85+ decibels is like to cause hearing loss

damage to hair cells

-central auditory projections travel via the auditory nerve to a FIRST synapse in the superior olivary nucleus in the medulla -then to a SECOND synapse in the inferior colliculi -then to a THIRD synapse at medial geniculate nucleus in thalamus (synaptic way station) -then finally to primary auditory cortex in temporal lobe of neocortex -info coming from LEFT auditory nerve crosses over to RIGHT side of brain at level of medulla (complete crossover) -several minor synaptic connections between auditory nerve and thalamus

Neural Pathway of Audition

-auditory perception processed differently than other sounds -stimulates activity in many more brain regions than just sound and requires more complex processing in coding -auditory perceptual system, in trying to perceive sounds, first tries to determine if the sound contains words, that then can be perceived via language system

Speech Perception

genes that code for disease-detecting structures that alert immune system to destroy them -many variants and both mom and dad's are expressed -mice, penguins, and humans pick partners with most dissimilar alleles than themselves -> based on odor

Major Histocompatibility Complex (MHC)

-cilia (dendrite-like) dangle into olfactory mucosa --cell bodies in epithelium -axon through criboform plate to synapse onto olfactory bulb -regular turnover of receptors every 3-6 weeks; new receptors mature in epithelium -over 900 genes for olfactory receptors, but ~400 expressed -binding of smells to receptors is much like NT bindings to NT to metabotropic receptor --odorants bind in lock-and-key fashion to receptors (odorants dissolve in epithelium) -odorants are complex chemicals, so different features attach to different receptors, which humans have 500-700 of

olfactory receptors

-SVZ neurons migrate down rostral migratory stream to olfactory bulb and become intraneurons -not involved in learning differences between novel and familiar odors -involved in species specific responses (ex-mating) -may be involved in learning fine discrimination and patterns differentiation.

subventricular zone (SVZ) neurogenesis in olfaction

used for timing of fast, coordinated muscle movements and responses to signals -> cerebellum

millisecond timing

seconds -> minutes -used for learning, coordination of movement, decision making, foraging -> basal ganglion-frontal cortex -usually unaware of it -use it for language, movement, waiting, etc -basal ganglion damage/malfunction (ex-Parkinson's Disease and ADHD) -some neurons in basal ganglia act as timekeepers -can be altered by drugs and arousal

interval timing (stopwatch timing)

around 24 hr -endogenous cycles of behavior biological activity with a period or ~24 hour -> suprachiasmatic nucleus/gene regulation/melatonin

circadian timing (clocklike timing)

bird migratory patterns, animals storing food for winter -> hypothalamus/gonadal hormones

seasonal rhythm

behavioral method by which you can teach mice two time intervals -> can be modified for humans

Peak Interval Procedure

critical for interval testing, as drugs can change perception of time -drugs like cocaine and amphetamine increase activation and speed up internal clock -other drugs that block production can slow down clock

Dopamine

study of biological rhythm

chronobiology

self-sustained biological rhythm which in an organism's natural environment normally has a period of approximately 24 hours endogenous cycles of behavior or biological activity within a period of 24 hr -generated by an internal clock in brain that is usually synchronized to light-dark cycles in the environment, as well as to other daily cues -> frequently plotted on an attogram -clock must be synchronized to local time to be most powerful, but can be free running -organism must be in sync with its prey, pollinators, and other members of its social group in order to survive -> usually set by light-dark cycle, butt can be set with meal time or sound cues

circadian rhythms

endogenous cycles of behavior or biological activity within a period greater than 24 hours

infradian rhythm

endogenous cycles of behavior or biological activity within a period less than 24 hr

ultradian

natural self-sustained rhythm that exists in absence of all environmental cues when organism is deprived of any cues to tell it about standard 24 hr cycle -> most organisms continue to show sleep-wake cycle ~24 hr (humans around 25hr)

free running cycle

diagram showing the periods of activity and rest of an organism over a number of twenty four hour periods so that trends in activity can be identified -features entraining agent and phase shifts (Dotted lines)

actogram

can cause a phase shift whereby the activity is started either earlier or later in the day an environmental time cue, such as light, that has the ability to reset a biological clock, another word for this is the German word Zeitgieber.

entraining agent

location of circadian clock -distinct group of cells found within hypothalamus, just dorsal to optic chiasm

suprachiasmatic nucleus (SCN)

-branch off optic nerve occurs just before optic chiasm -rods and cones signal specialized ganglion cells found in retina that contain melopsin, which have this pathway, leading to SCN -mammals use pathway to send light info to SCN and reset using rods and cons that use melanopsin -axon endings of this branch of optic nerve releases glutamate into SCN, which triggers a chain of events that promote the production of per protein

retinohypothalmic tract

-SCN is only ones part of mechanism by which "time" is kept -rods and cones signal specialized ganglion cells found in retina that contain melanopsin, which have this pathway, leading to SCN -lesions of the lateral geniculate nucleus or visual cortex, do not interfere with ability to ability of animal to set its clock to light cues --however, lesions of the retina or of optic Neve before chasm do prevent the clock from being set to light *SCN takes info on day length from retina, interprets it, and passes it to pineal gland, which secretes hormone melatonin in response two message -a couple hours prior to sleep, melatonin secretions rise but is inhibited by daylight --released cyclically in absence of light cues --if SCN is destroyed, circadian rhythms disappear

How does clock gets reset?

pea-like structure found behind hypothalamus -receives info indirectly from SCN -SCN takes info on day length from retina, interprets it, and passes it to this region, which secretes hormone melatonin in response two message --a couple hours prior to sleep, melatonin secretions rise but is inhibited by daylight

pineal gland

display free running rhythm due to no light cues -> can help by giving melatonin a few hours before bedtime each day

blindness and circadian rhythms

-blood pressure -muscle strength -testosterone levels -body temperature -sleep -drug metabolism-some drugs work more efficiently at some times of day than others -disorder-disfunction in disruption of clocks, such as clinical syndromes in which people wake up very early or go to sleep very early

functions in body that show a circadian rhythm

form of depression that strikes when day is short but not when day is long -if adding broad spectrum Iight in the morning improves the depression, then clinical psychologist will make this diagnosis

seasonal affective disorder (SAD)

an internal timekeeping mechanism capable of driving or coordinating a circadian rhythm

biological clock

self-sustained cyclic change in a physiological process or behavioral function of an organism that repeats at regular intervals

biological rhythm

taken form Latin words meaning "around" and "day"--thus meaning "approximately 24 hours"

circadian

performed in orr belonging to daytime -opposite of nocturnal

diurnal

generated by environmental cues that are external to the organism

exogenous

term that refers to an organism's endogenous period length

tau

recording of gross electrical activity of the brain via large electrodes placed on the scalp/skull -involves potential changes (summation of graded potentials NOT APs) that reflect the activity of many neurons at one time

Electroencephalography (EEG)

-a stage of sleep characterized by small-amplitude, fast EEG waves, no postural tension, and rapid eye movements -associated with dreaming -EEG contains fast, small amplitude waves of desynchronized neural activity -eyes move rapidly in coordinated patterns -heart rate and respiration rate are variable, with high bursts -cerebral blood flow and cortical neural activity area high -muscle tone is completely lost (atonia) -impaired thermoregulation

rapid eye movement (REM) sleep AKA paradoxical sleep

sleep, divided into stages 1-4, that is defined by the presence of distinctive EEG activity that differs from that seen in REM sleep

non-REM sleep

-brain potential of 8-12 Hz that occurs during relaxed wakefulness and Stage 1 sleep

alpha rhythm AKA alpha waves

sharp-wave EEG patten that is seen in Stage 1 sleep

vertex spike

initial stage of non-REM sleep, which is characterized by small-amplitude EEG waves or irregular frequency, slow heart rate, and reduced muscle tension -characterized by emergence of a rhythm in EEG activity --small amplitude waves with a frequency between 9-12 Hz = alpha waves -slow eye movements -EMG shows relaxation of body muscles

stage 1 sleep

stage of sleep that is defined by bursts of EEG waves called sleep spindles -bursts of waves with frequency of 12-14Hz -sleep spindles -emergence of K complexes and sleep spindles -more muscle relaxation than Stage 1 -little to no eye movement

stage 2 sleep

a characteristic bursts of 12-14 Hz waves in EEG of a person in stage 2 sleep

sleep spindles

sharp, negative EEG potential that is seen in stage 2 sleep

K complex

stage of non-REM sleep that is defined by presence of large amplitude, slow delta waves -EEG waves are in 5-9 Hz range with emergence of some delta waves -characterized by further muscle relaxation and emergence of v. slow eye movements

stage 3 sleep AKA slow wave sleep (SWS)

slowest type of EEG wave, about 1/sec, characteristic of stage 3 and 4 sleep ~1Hz waves with v. large amplitude -large amplitude occurs bc many neurons are firing in unison, highly synchronized

delta wave

a long, frightening dream that awakens the sleeper from REM sleep

nightmare

a sudden arousal from stage 3 sleep that is marked by intense fear and autonomic activation

night terror

partial or total prevention of sleep main consequences: -increased reports of sleepiness -reduced latency to sleep -irritability -> may also experience: difficulty concentrating and episodes of disorientation -effects most dramatic in wee hours of morning, when subject would normally be sleeping -interruption of circadian rhythm could contribute to effects of sleep loss/deprivation

sleep deprivation

process of sleeping more than normally after a period of sleep deprivation, as though in compensation

sleep recovery

unique assortment of environmental opportunities and challenges to which each organism is adapted

ecological niche

-experimental preparation in which an animal's brainstem has been separated from the spinal cord by a cut below the medulla -In Bermer experiments, though many of the same sensory inputs were severed as in other transections, it was found that this transection did NOT disrupt normal sleep-wake EEG

encephale isole preparation AKA-isolated brain

-experimental preparation in which an animal's nervous system has been cut in the upper midbrain, dividing the forebrain from the brainstem -> supported Bermer passive theory of sleep bc forebrain in cats showed almost continuous SWS

cerveau isole transection AKA-isolated forebrain

ventricle region in forebrain that has been implicated in sleep -area which can show SWS in Bain on its own -electrical stimulation of this area causes conical SWS -lesions to this area can abolish SWS

basal forebrain

region of the basal hypothalamus, near the pituitary stalk, that plays a role in generating slow wave sleep

tuberomammillary nucleus

drug that renders an individual unconscious

general anesthetic

-an extensive region of brainstem (extending from the medulla through the thalamus) that is involved in arousal -neural circuit that actively promotes wakefulness, as discovered by Moruzzi and Magoun in 1949 -postulated that decreasing activity in this region would lead to sleep and increasing activity would promote wakefulness -in brainstem, functions to arouse forebrain

reticular formation AKA reticular activating system

small nucleus in brainstem whose neurons produce norepinephrine and modulate large areas of the forebrain -neurons project throughout brain and initiate bursts of PGO waves that are associate with REM sleep -neurons in area just ventral to this region may be important for initiation of REM sleep -lesions to this area can abolish REM sleep -stimulation (electrical or neurochemical) induces REM sleep

locus coeruleus (LC)

disorder that involves frequent, intense episodes of sleep, which last from 5-30 min and can occurred anytime during the usual working hours

narcolepsy

sudden loss of muscle tone, leading to collapse of body without loss of consciousness -sometimes a component of narcoleptic attacks

cataplexy

a state, during the transition to or from sleep, in which the ability to move or talk is temporarily lost

sleep paralysis

bed wetting

sleep enuresis

sleep disorder in which a person physically acts out a dream

REM behavior disorder (RBD)

difficulty in falling asleep

sleep-onset insomnia

difficulty remaining asleep

sleep-maintenance insomnia

commonly, a person's perception that the has not been asleep when in fact he has -typically occurs at the start of a sleep episode

sleep state misconception

sleep disorder in which respiration slows or stops periodically, waking patient -excessive daytime sleepless results from frequent nocturnal awakening

sleep apnea

-sudden, unexpected death of an apparently healthy human infant who simply stops breathing, usually during sleep

sudden infants death syndrome (SIDS) AKA crib death

1)move through environment 2) manipulate surroundings 3) maintain posture and balance 4)communication (speech, gestures, etc) 5) autonomic movements (ex-respiration) 6) sensation turning (eye movements, head turn, etc)

functions of motor system

voluntary, motor programs, reflex closed vs open (including ballistic)

Classes of movement

speech, object manipulating -goal-directed -highly modifiable -can become motor programs with practice/learning -stimulus guided when new but no need for stimulus guidance once learned

voluntary movement

walking, swimming, chewing, etc -several muscle groups around limb/joint -relatively stereotyped -not necessarily graded with stimulus intensity

motor programs

system constantly receives feedback to fine tune movements -accurate but slow -ex-drinking from unfamiliar mug

closed loop movement

no feedback or control -feedback is disruptive -careful programming and anticipation of possible errors -fast but cannot respond to changes in environment ex-2000 Sydney Olympics gymnastics video

open loop movement

form of open loop movement -very rapid -preprogrammed movement often controlled by cerebellum -speed! ex-throwing darts -once started, hard to stop

ballistic movement

An accidental but humorous distortion of words in a phrase formed by interchanging the initial sounds -evidence that speech is open loop movement, as sentence must be preprogrammed by brain program

Spoonerism

1)sensory systems 2)planning and commanding areas (premotor cortex, supplementary motor cortex, and primary motor cortex) 3)implementation pathways (brainstem, spinal cord, musculoskeletal system) 4) modulation-feedback from muscles to brain (basal ganglia, cerebellum) -must have sensation in muscles-> feel stretch, contraction, weight, otherwise can't move properly

Parts of nervous system involved in movement control

-"nonprimary" motor cortex-higher level motor planning -primary motor cortex-site of motor initiation (specific movements) -spinal cord-controls muscles in response to sensory information and signals from the brain -musculoskeletal system (bones, joints, muscles, tendons)-execute movement -brainstem-integrates motor commands from higher brain centers; relays sensory info to brain -basal ganglia, cerebellum, etc - modulated movement

Components of Motor Hierarchy

controls muscles in response to sensory information and signals from the brain

spinal cord

integrates motor commands from higher brain centers; relays sensory info to brain

brainstem

direct routes from cortex to spinal cord to muscles -requires sensory feedback of movement -crosses over in medulla (R side movement, L hemisphere) -many neurons run from cortex all the way to spinal cord

pyramidal tract

"what should I do?" -integrates info from all sensory systems -decides how to respond --shifts focus/attention --filters information --identifies physical responses

prefrontal cortex

1) conserve energy 2) be less susceptible to predation BUT duration of sleep across species is hard to predicted based on either risk of predation or energy expenditure

Possible evolutionary value of sleep

provides a measure of eye movements -electrodes near eyes

electrooculogram (EOG)

provides a measure of muscle tension -electrodes on chins

electromyogram (EMG)

-during waking, brain waves have a very specific amplitude with rapid frequency -bc neurons in brain are performing a multitude of different function, their firing rates are desynchronized -as humans fall asleep, they brain activity alternates between distinct stages of sleep that are associated with different EEG pattens

sleep insights from EEG

stage of non-REM sleep that is defined by presence of large amplitude, slow delta waves -consists almost entirely of delta waves -characterized by further muscle relaxation and emergence of v. slow eye movements

stage 4 sleep AKA slow wave sleep (SWS)

-initially "drop down" through stages 1-4 and then come "back up" to REM sleep -this type of cycle repeats throughout the night and is about 90 min in length, on average -as night goes on, there is less Stage 3-4 sleep and more REM sleep -also changes in sleep stages across lifespan -time spent in REM sleep changes more dramatically than time spent in SWS from infancy to old age --need for sleep is high in infants and young children and declines as we age

Sleep stage pattern

in pons/medulla -sends long axons to cortex --these neurons manufacture and release serotonin -infusion of serotonin or stimulation of this region , makes animals sleep BUT recordings from this region indicate it is more active in day than at night, suggesting that firing of neurons in this region during the day builds up serotonin, leading to sleep

raphe nucleus

-has controversial role in sleep -infusion or stimulation of raphe nucleus , makes animals sleep BUT recordings from raphe nucleus indicate it is more active in day than at night, suggesting that firing of raphe nucleus during the day builds up of this substance, leading to sleep

serotonin

1) circadian rhythm and melatonin release 2) buildup of "sleepiness" or sleep need that occurs the more hours we're awake -> suggest that fine of raphe nucleus during the day builds up serotonin, leading to sleep

Two controls for sleep

basal forebrain, reticular activating system (RAS), pons (locus coeruleus), hypothalamic system, raphe nucleus

major sleep regulation areas

A brain structure that relays information from the cerebellum to the rest of the brain -seems to contain areas important to regulation of sleep -neurons in locus coeruleus project throughout brain and initiate bursts of PGO waves that are associate with REM sleep -neurons in area just ventral to locus coeruleus may be important for initiation of REM sleep -lesions to this area can abolish REM sleep -stimulation (electrical or neurochemical) induces REM sleep

pons

affects other three brain systems to determine sleep/wake -acts as switch for awake vs. asleep

hypothalamic system

-many people area able to function on a reduced amount of sleep without any noticeable cognitive impairment -if sleep is deprived, subjects can function normally for several days -> many confounding factors attributed to sleep loss/deprivation, such as stress -sleep deprived subjects will sleep more when deprivation ends (increases Stage 4 most on only the first day, with first day increases of Stages 1 and 2, and 3 day increase of REM) -since this theory predicts that sleep loss should result in recovery sleep, data is partially supportive BUT not a complete recovery of all sleep lost --since SWS (particularly Stage 4) and REM sleep debts are "repaid" this suggests they serve some specialized functions

sleep as homeostatic function debate

-evidence suggests that sleep promotes hippocampal neurogenesis possible normal development of brain -infant and child mammals sleep significantly more than adults (lately comprised of extra REM sleep, possibly assisting with selective strengthening and pruning of synaptic connections) -growth hormone for pituitary is released during stages 3 and 4 slow wave sleep -older adults have less stage 3 and 4 sleep than younger adults

restorative/developmental function of sleep

replaying of new memories and same firing of neurons "in rehearsal" occur during synchronized delta wave activity of stages 3 and 4 SWS -hippocampus needs downtime to replay memoirs to cortex in orders to train association in cortex -> similar to LTP

sleep's role in memory consolidation

more than any other species, humans can adjust to activity and sleep schedules -problem with 24 her lifestyle is that we're fighting against evolved systems of cyclic behavior ex-graveyard shift has more workplace accidents --rise of sleep disorders

impact of advent of artificial light