Quiz cognitive neuroscinece Flashcards
Frontal lobe
Higher Functions:
- Broca’s area
- Language/ speech
- Thought/planning/reasoning
- Memory
- Motor functioning
Orbitofrontal cortex: evaluate meaning
Occipital lobe
- Vision (Primary function)
- Where Visual Cortex is located (receives signals from eyes)
- Associated with visuospatial processing.
- Distance and depth perception.
- Object and face recognition.
Temporal lobe
- Language (Wernicke’s area –> understanding language)
- Memory
- Vision (Fusiform face area) + object recognition
- Hearing
- Taste
- Smell
Parietal lobe
- Somatosensory cortex: touch, temperature, pain
- Some aspects of visual information
- Spatial attention
What is cognitive neuroscience?
The study of the physiological basis of cognition.
What are levels of analysis?
A topic can be studied in different ways (at different levels of the same system). Each approach contributes in a different way, offers new dimensions.
What are neurons?
Neurons are specialized nerve cells that are designed to pass on electrical impulses (action potentials). They receive and transmit information in the nervous system.
A ________ is a network of continuously (uninterrupted) interconnected neurons. This idea was based on Golgi’s stain technique.
Nerve Net
How was it discovered that neurons are individual units?
Cajal used Golgi’s technique to look at brains of baby animals (where there were less neurons) and realized that the network is not continuos.
Neuron Doctrine - individual cells are called neurons and transmit signals in nervous system (they are not continuos).
What are the different parts and functions of a general neuron?
Dendrites - extensions that come out of the cell body and receive electrical signals from other neurons.
Cell body - part of the cell that contains the mechanisms to keep the cell alive. Where the nucleus is contained and where all the metabolic processes
take place.
Axon - transmits signals from cell body to synapse.
Terminal Button - last part of the axon. Where action potential is released into the synapse.
What is a synapse?
A synapse is the space between two neurons, where the nuerotransmitters are released.
What are receptors?
Neurons that detect external stimulus.
What is an action potential (nerve impulse)?
An action potential is an electrical signal passed from one neuron to another. They travel down a neuron’s axon.
Adrian was the first person to develop a technique to measure the electrical signal from single neurons. He had a reference microelectrode and an electrode inside the neuron to compare the voltage in both. Discovered inside of neuron is more negative than outside during a resting potential and the other way around during an action potential.
What is a resting potential?
The difference in charge between the inside and outside of the nerve fiber when the fiber is at rest. It’s usually -70mV
What is a neurotransmitter?
A chemical that is released at the synapse in response to incoming action potentials.
How does the intensity of sensation affect neuron firing?
More intense sensation = faster rate of nerve firing. Intense - Nerve impulses that are crowded closer together.
Feeble - Nerve impulses separated by long intervals.
What are neural representations?
The idea that everything we experience is a representation of what’s happening in our nervous system.
_______ were neurons that responded to specific stimulus in Hubel and Wiesel’s experiments with cats.
Feature Detectors
What is experience dependent plasticity?
The idea that neurons develop to respond to best to the type of stimulation to which the organism has been exposed. E.g., Cats that were only exposed to vertical lines will mainly have neurons to recognize vertical lines.
What is hierarchical processing?
processing that occurs in progression from from lower to higher areas of the brain depending on complexity of task. Also goes from back to front of brain.
What is Sensory coding and what are the 3 possibilities explaining how it works?
Sensory coding refers to how neural firing represents various characteristics of the environment.
Specificity coding- each stimulus has a specific neuron associated to it.
Sparse coding- neural coding associated with activation pattern of a few neurons.
Population coding- neural coding associated with the activation of a large group of neurons.
What is the idea behind localization of function?
Specific functions are associated with specific areas in the brain. It’s believed that higher functions happen in the cerebral cortex. Sometimes determined using neuropsychology.
What is Broca’s area?
Broca’s area is located in the frontal lobe and it’s associated with production of language.
Damage to Broca’s area can cause Broca’s aphasia, which is characterized by ungrammatical speech and difficulty understanding some sentences.
What is Wernicke’s area?
Wernicke’s area is located in the temporal lobe and it’s associated with understanding langauge .
Damage to this area can cause Wernicke’s aphasia in which people have difficulty understanding language, and fluent grammatically correct, but incoherent speech.
What is the difference between a simple dissociation and a double dissociation?
Simple - Damage to a specific brain area causes impediment in a function but damage to another area does not.
Double - Damage an area causes impediment in A but not B and damage in another area causes impediment in B but not A. Confirms that A and B are served by different mechanisms.
Double dissociation needs to be established to claim that a brain area is responsible for a specific function.
How does an fMRI work?
- More oxygen is demanded when an area of the brain is activated. Oxygen binding to hemoglobin changes its properties, making it more magnetic.
- Oxygenated hemoglobin responds strongly when magnetic field is turned on.
Colors in scan are not seen immediately, they are added later with mathematical processes that compares response when doing and not doing the task. Activity is recorded in voxels (small cubical units).
The fMRI creates the illusion that are are seeing the brain.
fMRI’s are bad at distinguishing what is happening overtime. Instead, it tells you the average effect. there are many stages of processing that happen in the first second, so we can’t see this with an fMRI.
The ______ is the area in the temporal lobe associated with face recognition.
Fusion face area
When damaged it causes prosopagnosia (inability to recognize faces).
The ______ is the area in the temporal lobe that contains neurons that are selectively activated by pictures of indoor and outdoor scenes.
Parahippocampal place area
The ______ is the area in the temporary cortex that is activated by pictures of body parts.
Extrastriate body area
What is distributed representation?
The idea that a specific cognition can activate many areas of the brain.
This happens mainly in cognitions that involve experiences.
What is multidimensional?
Even simple experiences involve combinations of multiple qualities.
What is a neural network?
Interconnected areas of the brain that communicate with each other.
What is the difference between structural connectivity and functional connectivity?
Structural - Brain’s wiring diagram (led to conecteome –> structural description of network of nerves forming the brain)
Functional - Extent to which neural activities in parts of the brain are correlated. Functionally connected doesn’t = neural pathway
What was resting state fMRI used for?
Used to identify which parts of the brain are correlated with certain activities.
1) fMRI to determine area associated with function (seed location).
2) Measure resting state fMRI at seed location.
3) Measure resting state in other brain regions (test location).
4) calculate correlation
If correlation is high then they are functionally connected.
What is the default mode network?
Functional network that increases activity when we are at rest (not doing any cognitive process). Associated with wandering.
What is cortical equipotentiallity?
Old idea that the brain operates as a whole rather than by specialized areas.
What is track-weighted imaging?
A technique to determine connectivity in the brain by measuring water moving though axons.
What is the cerebral cortex?
3mm thick outer layer of the brain that is associated with higher level mental processes (eg., thinking, language, problem solving and perception)
