lecture 2 Flashcards
define cognitive neuroscience
understand the underlying mechanisms of mental processes
what is mental representation?
anything that means something to the individual
what is posners letter matching task?
subjects responds same if both letters are constonants or vowels and press different if one of each.
results of the posner letter-matching task…
the reactions vary for different conditions- it takes longer to process that there are 2 consonants
what is chronometry
using time measures to infer the workings of the brain
Posner argues that the latencies in reactions reflect…
the degree of processing for each letter
what is stimulus onset asynchrony
same task but an interval between seeing the two letters.
describe the procedure of memory comaprsion (subdividing mental operations).
- asked to memorise a set of letters then choose if the letter was in the set after a delay.
what are the hypothesised stages in the memory comparison study?
encode, compare, decide and respond
what were the results of the memory comparison study?
reaction time gets bigger with set size.t
what theory came from the memory comparisons?
suggests that we compare every letter in the sequence even if we have already found it.
what are raster plots?
shows all the action potentials
what is the peristimulus histogram?
show us wether or not action stimulus change firing
during seizures…
all the muscles in the brain contract
How long ago was functional neurosurgery invented?
3000 years ago. Drilled holes in skull to release the demons
what did the freudian theory mean for functional neurosurgery?
the superego made people depressed so they had surgery and severed the connection between fronal lobes
define the term functional neurosurgery
altering the activity of the brain area by ablation, electrical or pharmacological methods.
single dissociation
impaired on one task and not another
double association
one gorup is impaired in one area but not the other whilst another group is impaired in the other area whilst not the othe.
what can cause brain damage?
trauma, stroke, tumors, neurodegenerative diseases and functional neurology
what is optogenetics
using light to manipulate neuronal activity
transcraial magnetic stimulation
low level currents that result in action potentials
fMRI
relies on BOLD- mainpulates hydrogen ions
what is posners matching task an example of
chronometry
when the stimulus onset asynchrony is introducedd to posners task what occurred
the interval is lengthened between stimulus the difference in reaction time between conditions decreases.
single cell recordings
more often used in animals to study them but occasionally used in treating epileps.
how can group studies investigate brain damage?
identify regions of lesions overlao between people.
