Cognitive Neuroscience Flashcards
What is neuropsychology?
Studies behavior of people with brain damage
What is Electrophysiology?
Studies electrical responses of the nervous system including brain neurons
What is cognitive neuroscience?
The study of the physiological basis of cognition
Levels of analysis
We look at topics of interest from many different perspectives. Each viewpoint adds small amounts that when added together create a greater understanding
What are neurons?
Cells specialized to create, receive, and transmit information to the NS
Parts of the neuron
Dendrites, cell body (SOMA), and an axon
Cell body
Has mechanisms to keep the cell alive
Dendrites
Multiple branches that RECEIVE information from other neurons
Axon
Tube filled with fluid that SENDS electrical signal to other neurons
Action potential
Neuron receives signal and info travels down the axon to be sent to another neuron
How to measure action potential
Through a microelectrode
What is a microelectrode?
A receptor that measures action potentials in nerves. Placed near the axon
Measuring Action Potential
Size is not measured, it remains constant
What is measured during AP?
Rate of firing
Low intensity: slow firing
High Intensity: fast firing
What is the synapse?
The space between the axon of a neuron and a dendrite of another neuron
When the Action potential reaches the end of an axon, ____________
synaptic vesicles open and release chemical neurotransmitters
What are neurotransmitters?
chemicals that affect the electrical signal of the receiving neuron
Excitatory
INCREASES chance neuron will fire
Inhibitory
DECREASES chance neuron will fire
Action potential results only if the _______ is reached
Threshold level
What is threshold level?
Interaction of excitation and inhibition
Definition of the mind
A system that creates representations of the world, so that we can act on it to achieve goals
Principle of neuronal representation
Everything a person experiences is based on representations in the person’s NS; Vision example
What did Hubel and Wiesel bring to the psych world?
Researched vision stimulus with cats; discovered feature detectors
What are feature detectors?
Neurons that respond best to a specific stimulus
The stimulus for vision is ________
Light
What did Hubel & Wiesel conclude?
Different neurons would respond to different orientations; different neurons respond to vertical stimuli, while others respond to horizontal stimuli.
If you did not have vertical line detectors, ________
You would not be able to see and recognize vertical lines
What is experience-dependent plasticity?
The brain changes with experiment
Kittens exposed to vertical-only stimuli over time___________
Could only perceive verticals in normal stimulus
A man losing the ability to walk learning to walk again through a separate part of the brain is an example of _________?
Experience-dependent plasticity
What did the kitten-vertical line experiment demonstrate?
demonstrated that perception is determined by neurons that fire to specific qualities of a stimulus
What is Hierarchical Processing
When we perceive different objects, we do so in a specific order that moves from lower to higher areas of the brain.
What is specificity coding?
Representation of a stimulus by the firing of specifically tuned neurons specialized to respond only to a specific stimulus; NOT USED
What is population coding?
Representation of a stimulus by the pattern of firing of a large number of neurons
What is sparse coding?
Representation of a stimulus by a pattern of firing only a small group of neurons
Is specificity coding, population coding, or sparse coding the accurate coding?
Population and/or sparse
What is localization function?
Specific functions are served by specific areas of the brain
What is the cerebral cortex?
3-mm-thick layer that contains the mechanisms responsible for most cognitive functions
Occipital lobe functions
Vision (lower level)
Parietal lobe functions
Somatosensory cortex (touch, pain, pressure) and spatial awareness (orientation, recognition, attention)
Temporal lobe function
Hearing, smell, speech, memory
Frontal lobe functions
Primary motor cortex, personality, speech, emotion, decision making, recognition,
Broca’s Area
Produces language; in left hemisphere of frontal lobe
Wernicke’s Area
Language comprehension; in the left hemisphere of the temporal lobe
Example of Broca’s Aphasia
Patients know what they want to say but can’t get it out; “Tip of the tongue”
Example of Wernicke’s Aphasia
Patients cannot comprehend what they are trying to say; “Word salad”
How do we know about certain area functions?
Brain imaging
What is the most common form of brain imaging?
Functional magnetic resonance imaging (fMRI) and
What does an fMRI do?
Measures neural activity by identifying highly oxygenated hemoglobin molecules
What is fusiform face area (FFA)?
Responds specifically to faces
What happens when the FFA is damaged?
Prosopagnosia (inability to recognize faces)
What is the Parahippocampal Place Area (PPA)?
Responds specifically to places (indoor/outdoor scenes)
What is the Extrastriate Body Area (EBA)?
Responds specifically to pictures of bodies and parts of bodies
What is the central principle of cognition?
Most of our experience is multidimensional; we use different parts of the brain to decipher events
What is Distributed Representation?
A specific cognition activates many areas of the brain; distributed across the brain
Neuronal Networks
Interconnected areas of the brain that communicate with each other
What is connectome?
Structural description of the network of elements and connections forming the human brain
Structural connectivity
What connects to what; “Wiring Diagrams”
How unique are structural connectivities?
They are unique to each person and change over time
Functional connectivity
How groups of neurons within a connectome function compared to types of cognition
What are the six common functions determined by resting-state fMRI?
Visual, Somato-motor, Dorsal Attention, Executive Control, Salience, Default Mode
Dorsal Attention
Attention to visual stimuli and spatial locations
Salience
Survival-relevant events in an environment
Somato-motor
Movement and Touch
Default Mode
Mind Wandering; not oriented towards a task
Executive Control
Higher-order functions and thinking
Dynamics of cognition
The flow and activity within and across the brain’s functional networks change based on conditions
