C/B Exam 1 Flashcards
`What is meant by ethics?
-how to treat animals in a good way
-voice (or lack of)
-minimize suffering
-best possible living conditions
-meaningful existence
-the concept of truth (scientific discovery)
-the greatest good for the greatest number
the greatest good for the greatest number of people
utilitarianism
The Five Freedom
FREEDOM FROM:
-hunger and thirst
-discomfort
-pain, injury and disease
-express normal behavior
-fear and distress
3 Rs of Animal research
-REPLACE: the use of animals whenever possible
-REDUCE: the number of animals needed to a min
-REFINE: tests to cause animals the least amount of distress
What is the US institutional level of ethics
IACUC – institutional animal care and use committee
what is the US federal level of ethics
USDA, AWA (implements and enforces the national animal welfare act)
responsible for the guidance on and for monitoring compliance with the Public Health Services policy on the humane care and use of lab animals
office of lab animal welfare (OLAW)
-prominent proponent for the humane treatment of livestock for slaughter
-stress, enrichment, etc.
Temple Grandin
why do we think about ethics in animal research
-to inspire thoughtful and qualified discussions
-good scientific practice
-animal welfare (maximizing good – minimizing suffering)
-regulatory issues
-interpretation by researchers
-research integrity
-research planning
-morality
-truth/scientific discovery
-founder of clinical and cognitive neuroscience
-coined the term “neurology”
-connected Brian (abnormalities) and behavior (autopsies)
Anne green & Thomas willis
-brain –> thoughts: ____ (then brain is source of thoughts *body and mind as one)
MONISM (Thales, armstole, ancient Egyptian)
brain (body) + mind were separate
Dualism (descartes)
-if you use one area more of the brain it’ll grow
-Franz Josef Gall
Modularity
-got rid of regions of the brain to prove parts are important
-Marie Jean Pierre Flourens –> aggregate field theory) the whole brain participates in the behavior)
connectome
speech impairments and left hemisphere lesions
marc dax
patients with epilepsy –> topopgrapguhucal map – homunculus (wilder penfield)
-topographical maps by stimulating different brain regions
-behaviors are complex – require coordinated activity of many regions
John hughlings Jackson
-aphasia (understand language but speech impaired)
-left hemisphere (inferior frontal lobe) syphilitic lesion –> Broca’s area
Paul Broca
-can’t understand language
-lesion –posterior left hemisphere –> _____ area
Carl Wernicke
characterized 52 distinct regions
Korbinian Brodmann
-diff staining methods (silver chromate)
cytoarchitecture
-syncytium: brain is a continuous mass that shares cytoplasm
Camillo Golgi
-neurons are discrete entities
-neuron doctrine
Ramon y cajal
-nervous system made of individual cells
-neuronal transmission in one direction
neuron doctrine
electrical current is a medium for information transfer in the brain, not a byproduct of activity
Hermann Von Helmholtz
coined the term synapse
sir Charles Sherrington
-inductive reasoning
-stats
-probabilities
-not concerned with personal mental States
logic
-knowledge can be gained though reason, truth is not intellectual not sensory
-grew out of enlightenment period
-replaced religion amongst scientists
-descartes, Leibniz, spinoza
rationalism
-all knowledge comes from sensory experience
-the brain is a blank space (Tabula RAZA)
-based on associationism (stimulus–> response)
-John locke, David Hume, John stuart Mill, Thomas Hobbes
empiricism
-learning & memory could be studied empirically
-THE FORGETTING CURVE
-the spacing effect
Hermaan Ebbingghaus
-rewarding stimulus –> response –> habit
-reinforcement learning
Edward Thorndike
-blank space (tabula rasa) philosophy
-anything can be learned
-in contrast to Philosophy
John b Watson (pure behaviorist)
-operant (instrumental) conditioning/ classisical conditioning
-Skinner box/ pavlov’s dogs
B.F skinner / Ivan Pavlov
adds positive stimulus so behavior continues
ex. you get a paycheck so u continue to go to wok
positive reinforcement
remove (negative) stimulus behavior continues
ex. take meds to get rid of pain
negative reinforcement
add (negative) stimulus behavior stops
-ex. u are embarrassed when drunk in front of friends so u no longer drink with them
punishment
remove (positive) stimulus behavior stops
ex. u feel less of a thrill each Time you skydive so u no longer skydive
extinction
-learning has a biological basis
*CELLS THAT FIRE TOGETHER WIRE TOGETHER
-neurons can come together in to a single processing unit: cell assembly
-connection patterns of these units make up the ever changing algorithms that determine a Brain’s response to a stimulus
-the brain is active all the time – sensory input modulates this activity
-artificial neural networks
Donald Hebb
-visual system, cerebellum, hippocampus, and memory
-highly influenced computation neuroscience and AI
-memory traces can be formed in the hippocampus –recurrent collateral CA3
-raphael lorrente de No
David Marr
-anatomical evidence for multiple memory systems
-cognition, not just behavior
-HM
Brenda Milner
-brain as a computer/information processor
-George miller rejected that only behavior should be studied
cognitive awakening / revolution
-associationism/ behaviorism could not explain how languages are learned
-Chomsky and George miller –> field of cognitive psychology emerged
-holistic/gestalt perspective
-interdisciplinary
-linguistics ands com sci –? psych and neuro
Noam Chomsky
-biochem, anatomy, electrophysiology, pharmacology, and behavior
-first description of the circuitry of the prefrontal cortex in the relation to working memory
-dopamine on PFC
-phase shift in the understanding mental illness ex. sz
patricia Goldman rakic
-typically in intact organisms
*ADDRESSES THE FUNCTION OF NEURAL CIRCUITS
-goal is to understand the function of the nervous system at a variety of levels, from single cells to entire networks that mediate complex behaviors such as vision, audition, social interaction, motor responses, and learning
-focused on how ensemble properties in the brain such as the activity of neuronal circuits –> giving rise to internal brain states and behavior
-traditionally involved electrophysiology recording sand computational approaches that attempt to decode how the brain transforms inputs and functional outputs
-more recently –> techniques that allow manipulation (optogenetics, chemogenetics) & imaging of neuron, neurocircuits, their inputs + outputs
systems neuroscience
these neurons take sensory information from the environment and sends the signal to the brain
sensory neuron
these neurons communicate info form the brain to tissues and organs throughout the body, allowing for movement
motor neurons
these neurons make up majority of the neurons in the body. they are essentially the “middle man” transmitting info between the sensory and motor neurons.
*key role in learning, memory, and planning
interneurons
what are the different types of neuroglia in the CNS
-ependymal cells
-astrocytes
-oligodendrocytes
-microglia
what are the different types of neuroglia in the PNS
-satellite cells
-schwaan cells
what are the different glial cells and what is their function
-astrocytes, microglial cells, and oligodendrocytes
-function: structural support, electrical insulation, and modulation
*CREATE BLOOD BRAIN BARRIER (btw CNS and blood)
-protect against solutes in bloodstream from entering the brain and allows hydrophobic O2, CO2, & hormones
-release NTs and modulates synaptic strength
—-directly or indirectly regulate repute
—-plays a role in plasticity
astrocytes
-form myelin (Schwan cells of this in periphery)
-squeeze out cytoplasm
-electrical insulator – facilitates salatory conduction
oligodendrocytes
-phagocytes (remove damaged cells)
microglial cells
do glial cells proliferate
yes
-cell body
-salty intracellular fluid (ions)
-Na, K, Ca, Cl
-proteins
Soma
-receive input from other neurons
-arborization – can be complex or simple
-spines (specialized processes)
-signals gathered
dendrites
-single process extending from cell body
-electrical signals travel along axon
axons
contains vesicles with NT
axon terminal
ome axons branch to increase signal transmission
axon collaterals
gaps in myelination
nodes of ranvier
specialized structure where neurons communicate
synapse
space between the neurons
synaptic cleft
-receive, evaluate, transmit info
-within a neuron
-between neurons
–chemical and electrical synapses
— presynatpuc and post synaptic
neurons firing –> action potentials
-energy is needed
neuronal firing
form of electrical impulse (initiated by a change in electrical potential)
energy
(-70 mv)
-voltage is determined by the difference in conc of Na, K, Cl ions insert and outside of cell
resting membrane potenial
measures voltage of neuron
oscilloscope
-transmembrane proteins
-ion channels & ion pumps
Membrane = lipid bilayer
-passive transport
-WITH electrochemical or concentration (ionic) gradient
Ion Channels
-selectively permeable to one type of ion
hydrophilic channel
the state of quality of a membrane that causes it allow liquids or gases to pass through it
permeability
-active transport (requires energy – ATP hydrolysis)
*AGAINST CONC GRADIENT
-2K in , 3Na+ out
—helps keep the inside of the cell negative
(THINK SALTY BANANA)
ion pumps
-start of the axon
-spike triggering zone
-summation converges here
-Na VGIC are densely found here & nodes of ranvier
-if summation results in membrane potential moving from -70 to -55 mV (threshold of excitation) then action potential triggered — neuron is depolarized — ALL OR NONE PHENOMENON
axon hillock
-threshold is reached (-55mV)
-Na+ VGIC open –> Na flows in
-positive ion influx further depolarizes neuron opening more VGICs
Depolarization
-at peak action potential (+30mV) K+ VGIC open allowing Ruch of sodium out of the cell and sodium VGIC closes
repolarization (process of shifting the membrane potential back toward resting)
Na+ VGIC close and since K+ VGIC stays open, cell becomes hyper polarized
-overshoots to about -80 mV –> refectory period
hyperpolarization
-during this state na+ VGIC cannot open again
refractory period
no action potentials can be generated
absolute refractory period
only large depolarizing currents can trigger an action potential
-limit cells to ~200 APs/sec
-APS are ALL OR NONE – amplitudes are the same – firing rate I important
-causes AP to propagate DOWN the axon
relative refractory period
-spontaneous firing without presynaptic action potentials
-most neurons fire in ____ manner
-neurons are active at some basal level
tonic signaling
depolarization of a neuron results in________- to open presynaptic terminal
voltage gate Ca2+
NTS travels across the cleft and either 1. binds to a receptor on the postsynaptic membrane and is broken down by enzymes or 3 taken up back into presynaptic cell _____
reuptake
-ionotropic/fast
-NT binds
–causes conformational change
-affects channel permeability
-“gates” or opens the channel
ligand-gated ion channels
-metabotropic/slow
-NTs binds to GCPR
-activates coupled G-protein
—exchanging GDP –> GTP
-indirectly gates channel via 2nd messenger signaling
— g-protein activation –> adenylate cyclase (AC) – converts ATP into cAMP as 2nd messenger
-slow but can have long-lasting modulatory effect
-DREADDS are GCPRs
G-protein-coupled receptors (GCPRs)
-synthesized within presynaptic neuron
-stored in synaptic vesicles (presynaptic terminals)
-released mediated primarily by Ca2+
-postsynaptic neuron contains specialized receptors for them to bind
-when applied to a cell, leads to postsynaptic potential
NTs
-Brain + spinal cord
-4 interconnected ventricles – also contain CSF
CNS
the walls of ____ contains a system of specialized cells and capillaries, the choroid plexus which produces CSF from blood plasma
*CONTAINS CSF FLUID
ventricles
protective membranes in CNS
meninges
what are the different maters in the brain
-outer brain
-middle arachnoid mater
-inner delicate pia mater (adheres to surface of brain) (thinnest layer)
*ALL ARE IMPORTANT FOR LUBRICATION OF THE BRAIN
the subarachnoid space in this mater is filled with cerebral fluid
middle arachnoid mater
bunch of cell bodies and their connections
-functional population
nuclei
neuronal cell bodies (what kind of matter contains this)
grey matter
axons organized into tracts or niches that cross the hemispheric projections
-main ex. is corpus callous
commissures
what are the benefits of the gyri
-increase S.A –> increase cells, increase processing, things can be close together
-consciousness
-sleep/wake
-breathing
brainstem, medulla, pons, cerebellum, & midbrain
-houses cranial nerve
-synapse in pons
-respiration, heart rate, arousal
medulla
-connections between brain and cerebellum
-cranial nerves synapse here
-sensory info passes through here
-houses part of the reticular formation
—important for modulating pain, arousal, and cardiovascular control
*GENERATES REM SLEEP
Pons
-contains 2/3 of neurons in the Brain
-vestibular functions: balance and posture
-integrates info with motor systems –> coordination
-auditory and visual inputs from brainstem
-higher order function ex. mental imagery, attention, & language
cerebellum
balance and posture
vestibular function
-contains periaqueductal gray (PAG)
-important for responding to threat; modulates pain, fear, & anxiety
-also contains superior and inferior colliculi
midbrain
perceiving objects in the periphery and orienting our gaze directly toward them, bringing them into sharper view
superior coliculus
locating and orienting towards auditory stimuli
inferior colliculus
-information relay station
-above brainstem
-fornix & corpus callosum above the thalamus
-all sensory info (*EXCEPT OLFACTORY) relay in the thalamus before heading to primary cortical sensory areas
-receives reciprocal projection form these areas
*smell not part of this and foes straight to limbic system
thalamus
what is the pathway for the retina
lateral geniculate nucleus –> primary visual cortex
what is the pathway for the inner ear
medial geniculate –> primary auditory cortex
what is the pathway for the somatosensory system
ventral posterior medial and lateral nuclei –> primary somatosensory cortex
-floor of the 3rd ventricle
-main link btw nervous system and endocrine system
-hormone synthesis and control
—-circadian rhythms, maintaining homeostasis (temp, electrolytes), stress, anxiety, fear, sex drive, thirst, and hunger
-pituitary gland
hypothalamus
anterior posterior pituitary
-produces hormones –> blood circulation, influence many behaviors
pituitary gland
-cingulate gyrus
-hypothalamus
-anterior thalamus
-hippocampus
-mammillary body
(CHHAM)
classical limbic lobe (Thomas Willis)
emotion
James Papez
-amygdala
-orbitofrontal cortex
-basal ganglia
Paul McLean
what are the functions of the limbic system
-memory (association and time), emotion, social information, motivational states
-most capable of plasticity
-smell and taste
-pain
-linking info
*limbic structure more flexible + plastic contrasted with cortical structures that are less emotional
what are the different structures that are part of the basal ganglia
-caudate nucleus + putamen * part of the striatum
-globus pallidus
-substantia nigra
-subthalamic nucleus
what is the basal ganglia function
-inputs from sensory and motor areas
-feedback from thalamus
-goal directed behavior
-reward-based learning (reward assessment, prediction, absence, etc.)
-largely dopaminergic circuit
-integrate goals and actions
what does the folding (sulci – crevices) and gyri (crowns) do in the cerebral cortex?
— what are the functions
-folded to increase surface area
-to bring structures closer together
-high density of cell bodies (appears gray)
-underside of brain appears paler because of axons
What does cognitive control consist of
-working memory
-response inhibition
-relational reasoning
*executive function
what happens during childhood and adolescence
- brain maturation
- cognitive and emotional advancement
-during adolescent, social and affective really impact decision making
-predicts success
-puberty + hormones –> affect bodily characteristics and social affective sensitivities
-increase risk-taking
-greater sensitivity to peer group influence
*mostly adaptive: stimulates learning and contributes to mature social functioning
– can also be maladaptive (ex. drug abuse + suicide)
affective decision making
what is working memory
holding memory in the brain and using pre-frontal cortex
ex. count backwards
in a WM task, adults show more activation in the __________ and ______ compared to children
lateral prefrontal cortex and posterior parietal cortex
in WM, age is also associated with lower activation in the _______ and _____
medial prefrontal and temporal cortex
what regions are important for WM
frontal and parietal regions
what kind of tasks are in WM
spatial, verbal, and visual
what is response inhibition
-ability to inhibit inappropriate responses
-Go-No-Go task
*right interior frontal gyrus – important for inhibitory response
*greater activation in adults compared to children
-hard for children
what region is important for inhibitory control
right inferior frontal gyrus
what is cognitive control
-relational reasoning
-integrating information to find new solutions, consider relationships between multiple mental representations
*relies on anterior PFC
-Raven’s progressive Matrices task
—sustained activation in adults but not other children
*when you see it you can’t unsee it
adolescents have higher sensitivity to both ___ and ___
risk and reward
value of reward involves what brain regions
-ventromedial PFC
-PCC
-ventral striatum (dopamine)
level of risk involves what brain regions
-insula (involved in processing disgust)
-dorosomedial PFC
what Brain regions is linked to risky behavior
functional coupling of the striatum and the OFC
what brain region is involved in delayed reward
lateral PFC
what brain region is involved in immediate reward
ventral striatum
-in adults ventromedial PFC more active compared to adolescents for immediate rewards
what social cognition and social brain development occurs in adolescence
-physical, social, behavioral and cognitive changes
-form more complex and hierarchical peer relationships
-more sensitive to peer acceptance
what does face processing do and function for
-identity, emotional expression, direction, of eye gaze, communicative signals
-with age, increased functional connectivity btw the fusiform gyrus (identity) & the superior temporal sulcus (STS) (emotional context)
function of fusiform gyrus
identity + face processing
function of superior temporal sulcus (STS)
emotional context
what is mentalizing
-understaning the mental state of others
-understanding that others hold different belief systems, intentions, thoughts, and feelings than you
-temporoparitenal junction (TPJ), superior temporal sulcus (STS), and dorsomedial prefrontal cortex (dmPFC)
-with age, you see less activation of dmPFC
what regions of the brain are involved in mentalizing
-temporoparitenal junction (TPJ), superior temporal sulcus (STS), and dorsomedial prefrontal cortex (dmPFC)
refers to the ability to make sense of of the world through processing signals generated by other members of the same species and encompasses a wide range of cognitive processes that enable individuals to understand and interact with one another
social cognition
refers to the interaction between our emotions and out behavior in the context of communication with others
social affect
ability to change structurally (anatomically) in response to a mismatch btw capacity (supply) and environmental (demand)
plasticity
what is the relationship btw plasticity and flexibility
flexibility = functional capacity (based on existing functional supply)
-using what you have to adapt
early plasticity linked to ____
vulnerability
synatogeneis tend to happen ___ in life
early
when does myelination occur
in the beginning
when does neural substrate appear highest
when flexibility is lowest in ontogenesis
what is neurogenesis
-the birth of new neurons
-different in rodents
-in adults, neurogenesis occurs at low levels in development and in 3 region of the brain: SVZ, lateral ventricles (migrate to olfactory bulb),amygdala, dentate gyrus of hippocampus
-when neurons are born they migrate to the paces in the Brian where they will reside, largely during fetal life
-neuronal differentiation is defined early, by place and time the neuron is born
what is neuronal loss
-apoptosis –> genetically determined
-humans don’t lose a great proportion of neurons with age, however there is neuronal shrinkage + average neocortical neuron losses of 2-4% from early to late life
Describe synaptogenesis
-starts in fetal stages, the peak number of synapses in the human brain is reached postnatally, and synaptic changes also seen in adulthood
— though development, there is considerable pruning or elimination of synapses
describe myelination
-insulation of neurons by glial cells while beginning in fetal life, taking place after birth an continuing into adulthood
-considerable loss of myelinated fibers in normal aging
-severe loss of myelin in multiple sclerosis
what does prenatal factors affect
-brain development despite rapid postnatal neural growth
postnatal environment also highly influential on ___
development
-period of heightened plasticity
-ex. sensory deprivation
what is critical period
specific window within Brian which is sensitive to environmental stimuli and must encounter that type of stimulus to develop optimally (ex. visual stimuli)
-think Genie
running increases ___
neurogenesis
what happens during postpartum period
-decreased neurogenesis (also in fathered because they show similar glucocorticoid profile
-increased glucocorticoids (tied to lactation in mothers and tied to contact with infant and mothers + fathers)
-in father’s there are more dendritic spines in prefrontal cortex
effects during postpartum period
-increased spine density
-decreased anxiety
-increased spatial processing abilities)
site of dendritic synapse
-increase in enriched environment + learning + exercise & decease in in stress
dendritic spine
increase oxytocin during sexual experience
dentate gyrus
what did Ramon Y Cajal discover
-parenting
-adult brain is more structurally stable
-Brain changes when needed
connection with retrospenial cortex, visual cortex, gene similarities with connected regions
-posterior in primates
-spatial navigation learning
-trace conditioning
-more innhibition
-more place cells
dorsal hippocampus
-direct connection with mPFC, more connections with amygdala
-gene expression similarities w/ connected regions
-anxiety regulation
-feedback of stress response
-decreased seizure threshold
ventral hippocampus (anterior in primates)
glucocorticoids functions
-activated & elevated during stress
Negative stress:
-decrease neurogenesis rate
-decrease dendritic complexity
-decrease synapses –> impair cognition + increased anxiety
-decreased memory and learning
Postive Stress:
increase glucocorticoids
-increase neuronal growth
-decreased anxiety
-increased learning and memory
-using light (photo stimulation) to control the activity of neurons that have been genetically modified to respond to light
-neurons are genetically modified using different types of viruses –> resulting in light sensitive opsin to be inserted into the cell
*can be done in transgenic or wild type animals
optogenetics
-viruses are used to transfect neurons with light sensitive proteins called ___
-these proteins were originally discovered in algae and bacteria
-these proteins respond to different wavelengths of light
-microbial ___ can be either excitatory or inhibitory
opsin
-shine blue lights on the cells that express ___, those cells will “turn on” or depolarize
-____ is an inotropic (fast)) ion channel that allows sodium to enter the cell producing an action potential
ChR2
sine green light ton cells that express ____ so that those cells will be inherited to hyper polarized
-____ is an ion-channel that allows chloride to enter the cell, inhibiting action potentials
ArchT3.0
light on cells that express ____ so that those cells will be inherited to hyper polarized
eNpHR3.0
how does optogenetics work?
- blue light activates “on” opsin called channelrhodopsin
- positively charged ions enter the neuron through channelrhodopsin resulting in firing of the neuron
- NTs released
- yellow light activated “off” opsin called haldorhodopson
- negatively charged ions enter the neuron though halrohodopsin stopping the neuron from firing
- the neuron doesn’t fire
*shining light happens through an implantation with an optic fiber that delivers light via laser beam
often opsin are fused to fluorescent reporter like ___ or ____
GFP – green fluorescent protein
RFP – red fluorescent protein
using the fluorescent proteins, you can visualize their location using ____ or _____
immunohistochemistry and fluorescence microscopy
describe the Tet-on, Tet-off system
-inducible and activity dependent system that you can control which cells you turn on and off
-system is inducible because controlled by TERACYCLINE
-when tetracycline is not present, this means that tTA can bind to TRE and u get the expression of the light sensitive opsins like ChR2 and the fused fluorescent resorted GFP
-when tetracycline is present, this blocks tTA from binding to TRE and nothing is expressed
*system is activity dependent because entire sequence is driven by c-Fos promoter gene and any cell that expresses this gene also expresses ChR2 and GFP (as long as no tetracycline present)
optogenetics provides ____ timescale precision
millisecond
optogenetics informs how the brain _____ when a certain pathway or subset of cells is not ______
compensates; assessible
what can be used to compare light off and on epochs in optogentics
within subject designs
true or false, optogenetics is an exact recapitulation of what happens in the Brain naturally
FALSE, it is NOT
what is the most significant factor diminishing light penetration in biological tissues
scattering
-wavelength-dependent – shorter wavelengths scatter more
-tissue penetration is less with blue light in comparison to red light and NIR
-light scattering arrives differently in different brain structures
*main determining factor is the DENSITY OF CELLS IN THE AREA, as cells nuclei scatter light more than axons and dendrites
what is the impact of optogenetics
-understanding how specific cell types contribute to the function of biological tissues
-identified many neural circuits in vivo important
-led to a variety of clinical insights (ex. anxiety, retinal disorders, memory impairments, Parkinson’s disease etc.)
describe the chemo genetics: DREAADs
-designer receptors exclusively activated by Designer drugs
-proteins engineered (GPCRs in the case of DREADDS) to interact with previously unrecognized (by the body), biologically inert, small, molecule chemical actuators (drugs)
-sustained activation (slower than optogenetics)
what does in vivo electrophysiology do
-record neural activity with spike timed precision but they cannot localize the activity of large populations of individual cells or identify cell types
*MEASURE APs (spike trains)
what does in vivo Ca2+ imaging do
enables visualization of activity of hundreds of neurons simultaneously using fluorescent activity sensors
-GCaMP – green fluorescent genetically encoded by calcium indicator (GECI)
—-it contains a CaM residue that binds the calcium
—-conformational change when calcium bound (doesn’t fluorescent when unbound)
-changes in fluorescence indicate fluctuations in the intracellular Ca2+, which is a indirect indicator of neural activity
-single cell resolution
describe fiber photometry
-can measure changes in NTs
—- grab sensors
-indicator is excited by a light source and in turn emits its own light
-when indicator is bound to a ligand, it emotes more light than when unbound
*the recored result is a trace of RELATIVE FLUORESCENE sensitive to the amount of ligand present for your indicator which increases in a way that correlates with action potentials in target neurons
what methods change the neural function
-optogenetics
-chemogenetics
-pharmacology
-genetic manipulations
-DBS
-TMS
what methods to measure neural activity
-in vivo calcium imaging
-fiber photometry
-electrophysiology
-EEG/ERP
-fMRI
-connectivity maps/Tissue clearing
-TMS
rhythmic and or repetitive electrical activity generated spontaneously and in response and to stimuli by neural tissue in the central nervous system
-enables and synchronization of neural activity within and across brain regions
-promotes the precise temporal coordination of neural processes and underlying cognition, memory, perception, and behavior
brain oscillations (waves)
-the measurement of electrical activity in different parts of the brain and the recording of such activity as a visual trace
-used as a diagnostic tool to detect epilepsy
-also used to study cognition across development as it is relatively non-invasive
electroencephalography (EEG)
what happens in P300
attend to a stimulus
what happens in N200
unexpected stimulus
N100 & P100
selective attention
50-100 ms
sensory
attentional states can modulate ___
ERPS
discovered that blood flow was directly related to brain function
Seymour Kety
-radioactive tracers injected into the blood
-more active areas have higher metabolic demand – receive more tracer
-decay over time allowing for metabolic inference via positron emissions
-positron colliding with electrons forms detectable gamma rays
-results reported as a change in regional cerebral blood flow (rCBF)
positron emission tomography (PET)
delay in reaction time between congruent and incongruent stimuli
stroop effect
brain damage is a _____ significance
clinical
what are examples of brain damage
-stroke
-aneurism
-tumors
-degenerative disorders
-viral & bacterial disorders
-traumatic brain injury (TBI)–> edema, epilepsy, and lesions
2 hemispheres are surgically severed (split brain patients)
callostomy
-callostomy
-removing a connection or a part of the Brian and seeing an impairment doesn’t always meant that part of the brain is involve in that process – important to include proper controls
-also imaging such as fMRI can help see what brain region missing or damaged
lesions
how does scary experiences change how people process new info
more sensitive to other negative life experiences
what brain regions are involved in fear
-amygdala
-hippocampus
-frontal + posterior regions
-noninvasive method for mapping the brain
-high resolution with good contrast between different tissues
*BOLD SIGNALING – areas of the brain that are more active tend to receive higher levels of oxygenated blood
fMRI
-nucleus of a hydrogen atom behaves like a small magnet
-NMR
-when you lay in the strong magnetic field of an MRI system all the HYDROGEN PROTONS in your body (most of which are in water) ALIGN WITH THAT MAGNETIC FIELD
MRI
when neural activity increases, MR signal also increases by ____
1%
fMRI limitations
-expensive
-person must be completely still
-cannot be used with patients who have metallic devices
-small sample sizes – lots of variability
-high levels of false positives
-lack of independent replication of experiments
-poor temporal resolution
-huge data sets
-microelectrode
-manipulations –> changes in firing and signaling dynamics
-rate of change in voltage
-raster pot
single cell recording (patch clamps)
-probe positioned in the extracellular space
-oscillation (like EEG)
-recording from multiple neurons
-available in many recording configurations, ranging from single-electrode recordings to multi-electrode arrays
local field potentials (LFPs)
similar to electrophysiology but for NTs
fast scan cyclic voltammeter (FSCV)
capture correlated pattens of activity between brain regions
—- brain regions do not work in isolation
-the connectome
-network
—– structural or functional imaging data
connectivity maps
what tis the 4 step process connectivity maps
-divide data into define anatomical nodes
-calculate correlations between nodes
-visually display this analysis with an association matrix
-create a connectivity map – color and geometrically code
-method to make tissue transparent
–using acrylamide -based hydrogels
–combined with other methods such as expansion microscopy (ExM)
tissue cleaning technique: clarity
-lipid content is removed, proteins and nucleic acids remain intact
-requires a transparent scaffolding (made of acrylamide)
-stabilized with formaldehydes
post-mortem tissue
-contrast for imaging
-confocal, sheet, 2P microscopy can detect ____
immunostaining
Fluorescence
describe Deep brain stimulation (DBS)
-invasive procedure
-electrodes are implanted to modulate neuronal activity
-exact mechanism is not full understood
-successful results for Parkinson’s
-implication for other disorders
-capacitor send electric current to coil – which generates a magnetic field
-magnetitic field propagates through the layers of scalp and skull altering the electrical activity (oscillations) of cortical neurons
-with a modest level of stimulation, the neurons fire
-new technology being developed to reach deeper structures
Transcranial magnetic stimulation (TMS)
term coined by Eric L Schwartz
computational neuroscience
