Midterm 1 Flashcards
What is cognitive neuroscience?
The study of how the brain and brain structures give rise to the mind and cognitive functions
Who was Golgi and what was his work?
Camillo Golgi is known for staining structures of whole, individual neurons
Who was Ramon Y Cajal?
He used Golgi’s method to discover that the brain was made up of discrete cells (neurons)
What has enabled modern cognitive neuroscientists to study the mind and the brain?
Brain imaging techniques
What is a neuron? Can you describe its structure?
The neuron is one of the cells that make up the nervous system. They consist of dendrites, a cell body, axon, and terminal buttons.
What is the other cells that make up the nervous system along side neurons?
Glial cells
What is a multipolar neuron?
A neuron that has many dendrites and an axon branching out
What is a membrane potential? What is a neuron’s resting membrane potential?
It is the difference in charge between inside of cell and outside. A neuron’s resting potential is ~-70mv
What maintains the resting membrane potential?
Na/K+ pump
Describe voltage-gated, ligand-gated, and nongated channels function
Voltage-gated opens and closes depending on the charge of an ion, ligand-gated depends on NT, and nongated are always open
Describe the ion concentrations at rest
More K+ inside the cell, more Na+ outside the cell
Describe the two forces that act on Na+ and K+ if channels opened
Chemical and electrical force would move Na+ into cell, chemical force would move Na+ out but electrical force would move it in
What is the purpose of the Na/K pump?
It maintains the concentrations
What does depolarizing and hyperpolarizing do to the membrane potential of the neuron?
Depolarization brings the membrane potential up, while hyperpolarizing brings it down
Explain the process of an action potential and the all-or-none principle
You already know this man
How is threshold reached for an action potential?
EPSP leads to small amounts of Na+ entering the cell
How can action potentials represent continuous information when action potentials fire all-or-none?
Many neurons are connected and represent some field of stimulus and perception
Compare and contrast relative and absolute refractory periods
Absolute is when the Na+ channels are inactivated, while relative follows hyperpolarization and requires more stimulus to activate
Why does an action potential tend to move in one direction?
Due to the refractory period preventing another action potential at the site
How does myelin affect action potential conduction?
Myelin insulates the axon, meaning there is no need to trade Na+ at a site as it will skip towards the node
What is saltatory conduction?
It is the process of an action potential jumping through myelin sheaths through the nodes of Ranvier
What is a synaptic transmission?
Communcation between neurons: electric synapse and chemical synapse
Whar are dendritic spines?
These are the sites of response retrieval in the dendrites of neurons
Describe chemical synaptic transmission
Neurotransmitters release from a presynaptic neuron, reacts to the receptors on the postsynaptic neuron, and then reacts accordingly
What is the difference between ionotropic and metabatropic receptors
Ionotropic has the receptor being the site of opening, while metabatropic involves G-protein cascade opening elsewhere
Define EPSP and IPSP
EPSP makes the postsynaptic neuron more likely to fire and action potential, while IPSP makes it less likely
How is NT ceased in the synapse
Reuptake or degradation
What is the advantage of reuptake over degradation?
Neurotranmitters are recycled and readily available compared to having to make new NT
Describe how EPSP and IPSP produce action potentials
EPSP probably opens Na+ while IPSP probably closes it
How does electrical synapse work?
The membranes are connected, allowing the action potentials to continue
What are the 4 types of glial cells?
Astrocytes, Oligodendrocytes, Schwaan cells, and Microglia
What are the difference between oligodendrocytes and Schwaan cells?
Oligo works in CNS and Schwaan does so in PNS
What makes up the CNS? PNS?
CNS: brain and spine, PNS: everything else
The PNS splits into the sympathetic and parasympathetic nervous system
What is the advantage of having the sympathetic and parasympathetic system?
It allows a faster stop in response (think of accelerator and brake)
What makes up gray matter, white matter, and where are these located in the brain and spinal cord?
Gray matter is the neuron while white matter is the myelinated axons. In the spinal cord, white envelops the gray, while in the brain it is the opposite.
What is a nerve?
A nerve is a bundle of axons in the PNS
What are gyri and sulci? What are their purpose
A gyrus is the piece of brain between grooves (the sluci). A fissure is a major sulci. The purpose of all these convolutions are to fit more brain matter in a smaller space
What are ventricles and what are their purpose?
Ventricles in the brain produce and spread the CSF around the brain
What is a homunculus?
It is an illustration on the sensitivity of of our bodies to our brain
What are two additional names for the primary visual cortex?
It is also referred to as the striate cortex or the visual area 1 (V1)
What is neurogenesis, and does it occur in the adult brain?
Neurogenesis is the process of creating neurons. Neurogenesis ends upon birth
What are the 5 types of research?
Case studies, observations, surveys, correlational studies, and experimental
What is a disadvantage of case studies and correlational work?
Case studies are unique and can’t be generalized, correlational studies cannot show causation
What does the Sternberg item-recognition task measure? Stroop task?
Both study working memory and what can be automatic tasks
What are three common causes of brain lesions and what case studies can tell us
Stroke, tumors, head injuries
These case studies can tell us what structures have a role in cognitive functions
What are two types of strokes and two types of brain tumors?
Hemhoragic stroke - blood vessel rupture and leak
Ischemic stroke - blood clot stops flow
Meningoma -
Glioma -
What are the strengths and weaknesses of studying naturally occurring brain lesions?
You can determine if a region is responsible for some cognitive task, but lesions rarely are contained
What is double dissociation and why is it important?
Double dissociation is the process of comparing two mental processes independently of each other. It allows us to see how much something will affect some cognitive function
What is experimental ablation?
It is the removal or destruction of a region of the brain for study
How do pharmacological studies show us knowledge of the nervous system?
By introducing NT in he body, we see how it changes reaction time or stuff
What is TMS and what are its strength and weaknesses?
Transcranial magnetic stimulation disrupts processing noninvasivly. Noninvasive, but too much variation in setup to be experimentally accurate
What do structural methods tell us about the brain? Functional methods? Give three example of each type
Structural methods show us images during cognitive processes: CT, MRI, DTI
Functional methods show us neuronal activity: EEG, MEG, PET
How does a CT scan work?
Tubes emit radiation that bounces back to give image
How does MRI work?
Use of magnets to yield an image
Very expensive
How does DTI work?
Use of MRI to view white matter tracts
How does EEG work?
Electrode placed in scalp to view population of neuron activity
How does fMRI work?
Measures oxygen levels as a means of use in the brain
What is Broca’s aphsia?
Trouble in the production of own speech, can understand others though
What is Wernicke’s aphasia?
Can produce speech, but trouble understanding others and using the right words to express self
What is the relationship between handedness and language lateralization?
A higher percent of left-handed people have speech and language in the right hemisphere
What are the five sense systems and their receptors?
Sight: photoreceptors Touch: free nerve endings Smell: olfactory Taste: taste receptors Hearing: hair cells
What is transduction?
It is the process of turning stimuli into electrical information
What are the four types of information about stimulus that is encoded?
Modality: the type of stimulus
Intensity: size of stimulus
Duration: how long the stimulus lasts
Location: where the stimulus took place
What’s the difference between sensation and perception?
Sensation is bottom-up and is the stimulus
Perception is top-down and is how we experience the stimulus
How do auditory hair cells work?
Certain frequency enter the ear and cause stretching of the membranes, which open the mechanoreceptors. This leads to action potentials to the brain
how are the cochlea and the primary auditory cortex organized?
They are tonotopic, meaning frequency is mapped on the cochlea and the brain’s temporal lobe
Does damage to the auditory cortex lead to deafness?
No, the nerve pathways are diffuse. Deafness comes from damage to the eardrum and the receptors
How does the brain calculate where a sound comes from?
Coincidence detectors
What are the functions of the olfactory and gustatory systems?
Both are used to detect chemicals in possible foods
How does the brain encode the identity of an odor?
It uses a pattern of receptors activated upon smell
What is unusual about the olfactory pathway?
It does need to go through the thalamus
What is the neural pathway for the gustatory system?
Taste receptors, cranial nerve, thalamus, cortex
What flavors don’t have receptors?
Salty and sour
How is spicy detected by receptors?
Not detected by taste receptors but pain receptors
How does satiation change activity in the brain in the gustatory system?
Satiation decreases hunger motivation
What is anosima? Aguesia?
Inability to smell, inability to taste
