Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
behavioral neuron
final exammm kms
| Question | Answer |
|---|---|
| what are the experimental lesions we've performed in animals? | tissue removal, tissue destruction, reversible lesions |
| pros and cons of tissue removal? | pros: precise, easy cons: non-reversible, non-specific, inadvertent damage |
| pros and cons of tissue destruction? | pros: controlled spreading, selectively kill neurons while sparing fibers cons: non-reversible, inadvertent damage |
| pros and cons of reversible lesions (cryogenic depression)? | pros: fully reversible, can be applied many times cons: not very localizable, can damage tissue with prolonged exposure, zone of hyperexcitability around cooled area |
| how does cryogenic depression work | EPSP magnitude and latency disrupted by cooling to test functional connectivity. slows down speech production |
| what are some reversible legions (pharmacological inactivation) we can use? | na+ channel blockers- block potential action potential. affects fibers inhibitory neurotransmitters- hyperpolarizes neurons and drastically reduce chances of firing by inactivating neuronal cell bodies where receptors are |
| neurological patient studies | used to make inferences about brain behavior relationships out of necessity |
| are trauma sites random? | no- ethmoid ridge, sphenoid ridge |
| what is single dissociation? | lesion to brain structure "a" disrupts function "x" but not "y" |
| what is double dissociation? | two areas of neocortex are dissociated by two behavioral tests, each being affected in one zone but not the other |
| what is tms? | transcranial magnetic stimulation "online" disrupts ongoing process (ex: deliver pulse when doing task) "offline" avoids interference, more heterogeneous effects |
| pros and cons of tms? | pros: minimizes possibility of plastic reorganization, repeated studies in same subject, can build a picture of which areas contribute to task performance cons: cannot stimulate medial or sub-cortical areas, not all brains are the same |
| are lesions driven by region or process | region |
| is functional neuroimaging driven by region or process | process: imaging brain function in real time |
| the brain is ... bloody | increase in neuronal activity>increase for glucose and oxygen>increase in CBF to active region is indirect, slow |
| the brain is ... electric | neurons communicate w each other by sending electrical impulses is a direct measure of neural activity |
| bloody techniques (hemodynamic): | position emission topography (pet) functional magnetic resonance imaging (fmri) pros: excellent spatial resolution cons: poor temporal resolution |
| electric techniques (electromagnetic): | electroencephalography (eeg) magnetoencephalography (meg) pros: excellent temporal resolution cons: poor spatial resolution |
| magnetic resonance imaging (mri) | strong magnetic field that protons align with, radio wave perturbs alignment. detectors pick up on signal of protons returning to magnetic field. different tissues have different densities of protons |
| fmri: bold signal (blood oxygen level dependent) | indirect measure of neural activity. fluctuation associated with cognitive processing oxygenated and deoxygenated blood have different properties no radioactive tracers needed, hemodynamic response function (4-6 sec lag) |
| fmri: event related design | allows the examination of brain areas that are active in response to different events occurring within a single task |
| fmri and pet: subtraction logic | task a: cognitive process of interest task b: as similar as possible but not does include cognitive process of interest |
| correlation | measure particular cognitive capacity in a task, then search for brain regions that are correspondingly activated to different degrees |
| local field potentials (lfp) | reflect summation of post-synaptic potentials. more closely related to lfp |
| multi-unit activity (mua) | reflects action potentials/spikes |
| fmri pros and cons? | pros: very good spatial resolution cons: low temporal resolution, very noisy |
| electroencephalography | post-synaptic current flow along dendrites of nerve cells picks up tangentially and radially oriented currents when neuron networks fire in synchrony, dynamics of electric activity can be detected and recorded outside the skull |
| eeg/meg | measures signals due to aggregate post-synaptic currents not action potentials- need to accumulate |
| how to increase SNR ratio? | average trials |
| what is evoked related potentials | event-related voltage changes in eeg that are time-locked to sensory, motor, and cognitive events |
| what does temporal analysis depend on? | latency, magnitude, and topography |
| temporal-spatial features? | distinct topographies at specific latencies. used for reflecting neural processing for cognitive functions |
| eeg pros and cons? | pros: millisecond resolution, non-invasive, assess system level states, signals added linearly, low cost, and simple use cons: highly distorted and incomplete representation of true neural activity. localization of neural generators complicated |
| eeg vs meg | electric potentials vs magnetic field same source: aggregated post-synaptic currents |
| how an meg works? | eeg picks up tangentially and radially oriented currents. currents perfectly radial are missed by meg, mostly picks up currents tangential to skull |
| how to capture tiny magnetic field signals? | superconductive sensors, reference channels, magnetically shielded room |
| what are reference channels? | measures signal from environment by subtracting signal from reference channel from raw data to remove environmental noise |
| what is the single dipole model? | discrete source model that assumes activity generated by point source. good way to reduce data spatial dimensionality |
| what is spectral domain? | ways to separate different oscillations by filtering components: distinct topographies in specific frequencies |
| what is spectral analysis? | neural oscillation view. depends on frequency, magnitude, and topography |
| meg pros and cons? | pros: aggregated postsynaptic potentials, better spatial resolution than eeg. tissues undistorted, tells about current generators cons: poor spatial resolution |
| what is internal forward model? | perceptual consequences of actions predicted by internal simulation of efference copy model, meg, and mental imagery uses sequential estimation and similar neural representation |
| what do lesions identify? | areas necessary for function (neuropsychology, lesions, tms) |
| what does imaging identify? | areas involved in a function (pet, fmri, optical imaging) |
| what do electrophysiological methods identify? | dynamics involved in a function |
| ffa dedicated to... | face perception |
| ffa domain general argument | face perception not special. computational level: expertise effect representation and implement level distributed network |
| visual field representation | v1>v2>v3 then higher order visual areas |
| information leaving visual "where" pathway | superior longitudinal fasciculus and posterior parietal cortex |
| information leaving visual "what" pathway | inferior longitudinal fasciculus and inferior temporal cortex |
| what causes motion after effect (mae)? | adaptation and velocity scale recalibrates |
| ventral stream observations... | receptive field get larger as you move from v1 to te include more foveal region. neurons are more sensitive to increasingly complex objects |
| object recognition | binding criteria: nearness of lines and color+coherent motion+experience |
| how do higher visual areas detect and recognize objects? | lines and colors represented by v1 neurons are assembled by higher visual areas to make recognizeable objects |
Created by:
zoraszzs
Popular Biology sets