Section 1 - Introduction to Attention Flashcards
Overview of Attention, Cognitive Neuroscience Methods
Descartes? (l2)
17th century contemplation about attention
Wolff? (l2)
18th Century psychology textbook discussed attention
Helmholtz? (l2)
19th Century physiologists ponder about attention (light and colour perception, built a box - first piece of equipment used to study attention)
Wundt? (l2)
1880s - attention central to growth of empirical psychology, so called father of psychology, used introspective method
introspective method (l2)
getting someone to do a task and then explain what they are thinking - in order to understand how the mind works
when did attention research go on pause? (l2)
1910-1960 ish, for 50 years
why did attention research go on pause? (l2)
John Watson said introspection was not legitimate science for studying the mind, that psychology should only study what is observable (and so no one studied attention because it wasn’t observable)
what did behaviourism accomplish towards the end of that era? (1910-1960 attention research pause) (l2)
B.F. Skinner - paradigm shift –> behaviourism. thanks to the behaviourists we have a more rigorous methodology
attention as metaphors? (l2)
not models -> more like analogies. include: filter metaphor, resource metaphor, spotlight metaphor, glue metaphor
what are the parts (lobes) of the brain and their main functions? (l3)
- Occipital Lobe: Vision
- Temporal Lobe: Auditory cortex +, some visual processing
- Parietal Lobe: most interesting for attentional processing - related to attention deficits)
- Frontal Lobe: in control of things, executive center
Paul Broca? (l3)
1880s, localization of language area/specialized language area (speech PRODUCTION issue - aphasia), brocas area
Wernicke’s patient was important how? (l3)
language area (left hemishpere), problem with UNDERSTANDING speech
Franz Gall’s contributions (l3)
- magnificent proposal. first to explain why our cortical tissue in brain is folded, because there is too much of it.
- also grey matter (cell bodies of neurons), and white matter(fatty stuff around myelin)
- not so magnificent proposal: phrenology - analysis of skull could describe personality of the person
Karl Lashley (l3)
memory area in rats - (destroyed part in brain and tested memory - didn’t work) ,’, memory must be distributed everywhere
Modern Lesion Methods (l3)
chemical deactivation and temperature change (lesions are temporary)
what is the Leyden Jar? and what was it used for? (l3)
get electricity into the jar and use it to touch different objects - to see if they could understand electricity with this new apparatus (related to the brains neural “electricity”)
who touched frog legs to the Leyden jar and what did that discover? (l3)
Luigi Galvani - the frog legs kicked out ,’, organic tissue was related to electricity
who was Cajal? (l3)
gets credit for refining the neuron proposal - father of neuroscience. proving that independent neurons/nerve cells are the building blocks of the central nervous system (that there were gaps between neural bodies)
how does the sodium-potassium pump work? (l3)
channel opens up, positively charged sodium ions (Na) flow inside, negatively charged potassium (K) flies out, voltage changes down the axon to the synaptic gap, spits out neurotransmitters into the synaptic gap and then sucks them back in
how did studying attention in animals start? (l3)
started with vacuum tubes - amplifying really small voltages so they are measurable (1960s). because there was no way to measure the brains electricity without a way to amplify it
measurement unit for electrical potential difference - the worth of millivolts and microvolts (l3)
millivolt: 1mV - 0.001 (V) [10^-3]
microvolts: 1uV - 0.000001 (V) [10^-6]
not done single cell recording (l3)
can be used in microstimulation (insert voltage into brain and used to map out the brain) (rarely used on humans)
who was Hans Berger? (1873-1941) (l3)
known as the first to record electroencephalograms (EEG) from humans and discovered the rhythmic Alpha brain waves
what are scalp maps and what are they good for? (l3)
a way to measure changes in the brain activity. they are good and precise at measuring changes brain activity within millisecond precision - WHEN brains start being active and when they stop being active. (lighter colours = more change; darker colours = less change)
what do EEGs do? (l3)
EEG records electrical activity of the brain through electrodes affixed to the scalp. study measures electrical activity in brain in response to stimulation of light, sound touch. the waves measured can tell us a lot of things (sleep waves)
what are ERPs? (l3)
focusing on what happens to the wave right after a stimulus is presented (there are neurons associated with attention in the parietal cortex). tells us when neural activation occurs (not as good at where)
structural vs functional imaging? (l3)
- structural: used to quantify brain structure
- functional: used to study brain function, shows you WHERE brain activity is occurring
structural imaging examples (l3)
x-ray, CAT scan (computerized axial tomography), can look inside ourselves and see 3D shapes
how do CAT scans work? (l3)
x-ray source and detector on opposite sides (180 degrees) and rotating around. machine is producing a set of 2D slices. this is good for detecting brain bleeding (show you where blood is leaking)
examples of functional imaging and how it works (l3)
PET, fMRI. (blood flow indicates locations of increased brain activity during mental processing. when different brain areas are active, the demand for freshly oxygenated blood is going up (neurons need a lot of oxygen, even a few minutes without oxygen neurons start to die).
how do PET (Positron Emission Tomography) scans work? (l3)
injects radioactive tracer into blood stream, and this has unstable subatomic particles in it called positrons. positrons don’t exist unless you create them, some radioactive tracer is needed. they are positively charged and electrons evil twins, when they meet electron they annihilate each other and create energy (light), 2 photons). these 2 photons split off in opposite directions at the speed of light. based on the arrival time differences it takes to reach the edge, you can tell where a lot of these collisions are happeneing
what is the current best functional neuroimaging method? (l3)
fMRI (can be like a pet scan, not so much real time, but from one moment to the next where brain activation is). tells us where, just not when.
how does BOLD (blood oxygen level dependent signal) work? (l3)
scanner has huge magnets that pulse.
red blood cells (hemoglobin) have iron in them so they can be magnetic, so when the magnets are pulsing, these blood cells can resonate with the pulsing magnets.
freshly oxygenated blood (diamagnetic) is differently magnetic than de-oxygenated blood (paramagnetic).
diamagnetic blood is repelled by magnetic field.
paramagnetic blood is attracted to magnetic field. the blood will react differently depending on if it is oxygenated or de-oxygenated.
way more precise than scalp maps, but temporally these things take a lot of time (limitation).
how does TMS (transcranial magnetic stimulation) work? (l3)
there is a wand that is placed over the head in a specific area and will affect the neurons that are close to the scalp. TMS virtual lesions can help people recover from spatial neglect
when were the first modern efforts to explore this idea of attention? (r2)
half a century after James - world war II with the combat pilots, they had to monitor multiple signals on screens in cockpits
when was attention investigated in peaceful situations? (r2)
1950s - ex. cocktail party effect
when did neuroscience transform the study of behaviour - specifically attention? (r2)
1960s - due to what the new technology (fMRI and MEG) revealed, that scientists could see activated parts of the brain by different colours lighting up
is there a tidy attention center in the brain? (r2)
no, says research now. but the parietal and frontal cortexes are especially important in the processes of alerting and orienting what is going on and pointing to an appropriate response.
what is the Stroop affect? (r2)
when examining a word for something as cursory as ink colour, the meaning of the word is also processed automatically.
why is attention considered an “umbrella” term among many researchers? (r2)
because there are several different operations that work together as a network when performing tasks that require attention:
- thalamus plays major role in attentional emphasis of stimuli
- posterior parietal cortex appears to be involved in sustaining attention and in disengaging it when a particular operation has been completed.
- midbrain appears to be involved in guiding focused attention from one location to another
