Week 6 - Neurobiology Flashcards
central/peripheral nervous systems
Central Nervous System is made up of the brain & spinal cord. The Peripheral Nervous System is everything else (nerves/neurons)
white matter
composes regions of the nervous system that represent the axons of the nerve cells; whitish in colour because of the myelin sheath.
grey matter
composes the “bark” or cortex of the cerebrum, consisting of the cell bodies. It is around the exterior of the cerebral cortex.
diencephalon
sits on brainstem, contains the thalamus and hypothalamus, which direct information and regulate hormones respectively, regulate our basic functions
cerebellum
located behind the cerebrum. It is responsible for balance, equilibrium, movement and muscle tone, but recent research also suggests that it is involved in just about everything.
limbic system
loosely defined network of nuclei involved with learning and emotion.
It is made up of the amygdala and hippocampus
contralateral functions
represented by the opposite side of the brain. For example, the left hemisphere is responsible for movement and sensations on the right side of the body.
lateralized functions
reside primarily in a single hemisphere. For the majority of people, the left hemisphere is most responsible for language.
Split-brain patients
hemispheres are not connected either because the corpus callosum was surgically severed or due to a genetic abnormality, help us to understand the functions of the two hemispheres (see less competition between the two hemispheres, allowing them to complete two complex tasks at once)
transcranial magnetic stimulation (TMS)
interfere with neuronal communication, allowing for precise study of when events happen in the brain.
Positron emission tomography (PET)
records blood flow in the brain to determine which regions of the brain are active and therefore require metabolites during a specific task.
Functional magnetic resonance imaging (fMRI)
measures changes in the oxygen levels in the blood.
Both of these tools have good spatial resolution (studying the area), but poor temporal resolution (studying the time).
Electroencephalography (EEG)
measures the electrical activity of the brain, giving it a much greater temporal resolution. The electrodes pick up on electrical activity from anywhere in the brain, thus giving it very poor spatial resolution.
Diffuse optical imaging (DOI)
shining infrared light into the brain and measure how much light comes back out. relies on the properties of light change when passing through oxygenated blood. DOI can have both high spatial and temporal resolution if set up properly.
Structural magnetic resonance imaging (sMRI)
noninvasive technique that allows the viewing of anatomical structures within a human.
-exposing the brain to a magnetic field, causing the atoms to line up, and then pulsing the body with radio waves to cause them to tip over. As they return to their aligned state, they give off energy which is measured and used to create an image.
Functional magnetic resonance imaging (fMRI)
used to assess changes in neural activity during specific processes, for identifying specific areas of the brain that are associated with different physical or psychological tasks.
- measures change in the oxygen transported through the blood using hemoglobin to show which areas of the brain are requiring more metabolites, and therefore are more active, during processes.
- data does not measure neural activity directly, but instead measures blood volume and blood flow which are correlated with activity.
- poor temporal resolution; however, when combined with sMRI, can provide excellent spatial resolution
Electroencephalography (EEG)
studies brain activation using as many as 256 electrodes to measure the voltage (difference in electrical charge) between different points on the head.
- measures neural activity directly.
- electrical activity must travel through the skull and scalp to reach the electrodes, localization is less precise.
- very high temporal resolution, however.
Magnetoencephalography (MEG)
measures the weak magnetic fields generated by the flow of electrical charge associated with neural activity.
- same excellent temporal resolution of EEG, but because magnetic fields are not distorted by the skull, it also provides much better spatial resolution.
- significantly more expensive.
Positron emission tomography (PET)
relies on positron-emitting tracer atoms introduced into the bloodstream via biologically active molecules such as glucose, water, or ammonia. molecules concentrate in areas which they are needed, and the positrons emitted by them are then picked up by a sensor to determine the spatial location of the molecules.
- used to determine which areas of the brain have the highest metabolic needs, which are typically the most active.
- very poor temporal resolution, as it relies on the emission of positrons, but can be combined with CT scans to improve spatial resolution.
Transcranial magnetic stimulation (TMS)
causes depolarization or hyperpolarization of neurons near the scalp. localized on certain areas of the brain to block functions such as motor activity, which can be used to study the function and timing of specific processes such as the recognition of visual stimuli.
-explore neural plasticity (the change in synapses and neural pathways as they adapt to changes in neural processes, behaviour, or environment).
Skin conductance
measures the electrical conductance between two points on the skin, which varies with moisture levels. Sweat glands, which are responsible for this moisture, are controlled by the sympathetic nervous system (SNS)
Cardiovascular measures
include heart rate, heart rate variability, and blood pressure. The heart is innervated by the parasympathetic nervous system (PNS)
Electromyography (EMG)
measures electrical activity produced by skeletal muscles. EMG can measure when a participant first initiates muscle activity in response to a stimulus.
autonomic nervous system
connects to glands and smooth muscles, allowing the individual to have little control over certain muscles and glands.
-made up of sympathetic and parasympathetic nervous systems.
sympathetic nervous system (CNS)
division of the autonomic nervous system that works faster than the parasympathetic system and often in opposition to it. It controls “fight or flight” functions.
parasympathetic nervous system (PNS)
curtails undue energy mobilization into muscles and glands and modulates the response, working to regulate the sympathetic system. It is generally engaged in “rest and digest” functions.
Broca’s area
lower end of the central sulcus, and is involved in language production.
Wernicke’s area
below the parietal lobe, and is involved with language comprehension. It is connected to the Broca’s area through nerve fibers known as arcuate fasciculus.
Agnosias
inabilities to know or understand language and speech-related behaviours, and occur as a result of damage to Wernicke’s area.
Immunocytochemistry
staining tissue, including the brain, using antibodies. Advancements in staining techniques, as well as the advent of electron microscope technology, make it possible to see selected neurons that are of one type or another, or are affected by growth.
Higher resolution microscopes allow for the study of finer structures, such as the synaptic cleft.
lesion studies
involve the study of neurological damage, and can provide information about the function of the nervous system by documenting the effects of damage on mental behaviour.
