Cognitive Neuroscience - Week 2 Flashcards
Visual Evoked Potential (VEP)
with the use of the VEP, it acts as a confirmation of visual selection and offers direct communication between brain and machines.
what area(s) of the brain highlight with motor coordination.
supplementary motor cortex (SMA)
*brain activity is indistinguishable between people “locked-in” and not
what area(s) of the brain highlight with spatial navigation?
premotor cortex (PMC)
posterior parietal-lobe (PPC)
parahippocampal gyrus (PPA)
THE NERVE!
dendrite
absorbs chemical stimulation from other neurons
THE NERVE!
soma
if dendritic activity is large enough an electric action potential will be fired
THE NERVE!
axon
conducts the electrical signal to terminal buttons at the end of the axon
THE NERVE!
terminal button
turns the electrical signal back into a chemical squirt
THE NERVE!
synape
the jump the chemical has to made to be taken up by the next dendrite
Stimuli and Firing Rate
the magnitude of the action potential doesn’t vary, but the firing rate does
i.e. increased luminance leads to increased firing
FEATURE DETECTORS!
simple cells
responds to size, orientation, or colour
FEATURE DETECTORS!
complex cells
responds to orientation and direction
FEATURE DETECTORS!
end-stopped cells
responds to orientation, direction and size
Blackmore and Cooper
cats exposed to vertically striped cylinder and neurons were only responsive to this orientation and were essentially blind to other orientations.
Hirsch and Spinelli
cats were exposed to vertical lines in one eye and horizontal lines in the other. each eye was only responsive to the orientation to which they were exposed to and were “blind” to the others
neural circuits
neurons form hierarchical processing depending on how they connect to one another
specificity coding
only one set of neurons respond to said stimulus
population coding
neural signatures are developed in response
sparse coding
subset of active neurons. only a select few neurons respond while the others don’t
forebrain
hypothalamus involved in hormone release and appetite. limbic system includes amygdala and hippocampus
midbrain
includes reticular activation system, which controls consciousness, heartbeat, etc.
hindbrain
basic biological functions controlled here such as swallowing and digestion
frontal lobe
information coordination!
- perception and decision making
- semi-permanent sense of self
- current events
temporal lobe
auditory processing!
- audio information
- store representative information for sensory objects
parietal lobe
touch, temperature, and pain!
- direct stimulation can lead to illusive sensory experience
primary somatosensory cortex
the organizational properties!
there is a continuity between body parts and larger areas relate to greater sensitivity.
*primary motor cortex is also organized
phantom limb
phantom limb occurs after the amputation of a limb and the brain hasn’t completely registered the loss of said limb
the treatment for it and its pain involves the use of a mirror
*signal crossing over occurs after the loss of a limb
occipital lobe
visual processing!
this is the place to wear all visual processing begins and is also the distributer of translated information
patient sm
visual agnosia!
the fusiform face area (FFA) stopped recognizing faces and was trained to recognize different species of greebles.
*he was the only one able to
phineas gage
received damage to his frontal lobe and was still able to live. he suffered a personality change. he also died x amount of time later.
broca’s aphasia
non-fluent verbal communication (expressive)
wernicke’s aphasia
fluent verbal communication (receptive)
lesion studies
damage incurred to a section of the brain is responsible for the viewable informal changes
association deficits
shared underlying damage that is causing two problems
single dissociation deficits
damage has occurred, but only one of two similar functions have been affected, performed by different areas
double dissociation deficits
two patients with opposite dissociations
transcranial magnetic stimulation (TMS)
sends weak magnetic fields across the cortical surface, leading to temporary (non-permanent) disruption of electrical activity
*safe way of stimulating lesions
**not long lasting effects, but not for epileptic samples
event-related potentials (ERP)
records the weak electrical fields generated by large scale neural ensembles that permeate out through the skull
*incredibly precise temporal reading
**spatially diffuse
positron emission topography (PET)
after ingestion of a radioactive tag which attached itself to glucose, glucose uptake related to increased brain activity
*allows for insights into functionality of brain regions
**poor spatial resolution and involves radioactive substances
magnetic resonance imaging (MRI)
records bold signal on the principle that oxygenated blood has different magnetic properties than deoxygenated blood
*fMRI is popular in revealing brain networks
**bold signal is very slow
