Cognative Flashcards
know everything
Cognition definition
Set of all mental processes that allow us to aquire knowledge/understanding through though, experience and the senses
Criticisms of the view that humans are stimulus response machines
Does not allow for parallel processing
Ignores top down processing
Top down processing
Stimulated by the individuals prior knowledge etc
Bottom up processing
Stimulated by external stimuli
Evidence that neurons represent specific information
Found a certain set of neurons fire when Luke Skywalker is mentioned (similar ones firing when other star wars things mentioned)
Rate coding
A greater rate of neuronal response is used to represent information
Temporal coding
A greater synchrony of neuronal responses is used to represent information
Possible types of coding (2) and which is more likely
Rate and temporal coding, temporal being more likely based of evidence
Different approaches to studying cognition (3)
Experimental Cognitive Psychology
Cognitive neuropsychology
Cognitive neuroscience
What is experimental cognitive psychology
Studying behaviour in lab setting (with manipulations), traditionally focusing on behavioural measures
Limitations of experimental cognitive psychology
Ecological validity (real-world translation)
Only indirectly measures cognition
Relies heavily on theory
What is Cognitive neuropsychology
Studying cognition in brain damaged patients to find specific brain areas role in cognitive functions
Limitations of cognitive neuropsychology (4)
Rare to get pre-damage measures for patients on performance
Often has complex damage in several regions
All brain damage is unique
the brain is unlikely to be modular
What is cognitive neuroscience
Relates brain structures and function to cognitive processes, usually by recording brain activity while tasks are completed
Tools in cognitive neuroscience (4) and their use
EEG for electrophysiology imaging
MRI for structural imaging
fMRI for functional imaging
TMS and TCS for brain stimulation
Single cell recordings
Very small electrode recordings from within an axon, or outside an axon membrane
When are single cell recordings used
Usually just on animals but known to be used on epileptics
EEG
Via electrodes in the scalp, it records the electrical activity of a large number of neurons firing together
Event related potential (ERP)
Average waveform from a task recorded multiple times, used to compare between conditions
Advantages (3) and disadvantages (2) of EEG
Adv: good temporal resolution, portable, cheap
Disadv: Spatial resolution, only measures brain’s surface
How MRI machines work
Very strong magnetic field (0.5-0.7 Tesla’s) on scanned area with single protons aligning to it. Alignment disturbed by short radio frequency pulse and the change is measured - different tissues realign at different times, giving brain map
Diffusion Tensor Imaging (DTI)
For structural imaging, it measures white matter (axons) by measuring the direction of water diffusion
How fMRI works
Doesn’t measure neural activity, it measures BOLD signals - oxygenated blood has higher signal than deoxygenated as it has less magnetic field disturbance
What does BOLD stand for
Blood Oxygenation Level Dependent signals