Week 6 Flashcards
Brain stem
sometimes referred to as the “trunk” of the brain. Responsible for many of the neural functions that keep us alive, including regulating our respiration, heart rate, and digestion
Includes the medulla, pons, midbrain, and diencephalon (consists of the thalamus and hypothalamus)
Cerebellum
distinctive structure at the back of the brain. Critical for coordinated movement and posture. Contains the greatest number of neurons of any structure in the brain
Cerebral hemispheres
responsible for our cognitive abilities and conscious experience
Consist of the cerebral cortex and the accompanying white matter as well as the subcortical structures of the basal ganglia, amygdala, and hippocampal formation
Largest and most visible part of the brain
Consists of two hemispheres and gives the brain its characteristic gray and convoluted appearance
Folds and grooves of the cerebral cortex
Gyri and sulci
Occipital lobe
responsible for vision
Temporal lobe
involved in auditory processing, memory, and the multisensory integration
Parietal lobe
houses the somatosensory cortex and structures involved in visual attention, as well as multisensory convergence zones
Frontal lobe
Houses the motor cortex and structure involved in motor planning, language, judgment, and decision-making
Basal ganglia
critical to voluntary movement and as such make contact with the cortex, the thalamus, and the brain stem
limbic system
A loosely defined network of nuclei in the brain involved with learning and emotion
Amygdala
responsible for emotional responses, especially in situations involving anxiety, fear, or rage.
hippocampus
with your learning and memory. It converts short-term memories into long-term memories by organizing, storing and retrieving memories within your brain.
split brain patients
corpus callosum was surgically severed (callosotomy) or due to a genetic abnormality. Because of the contralateral representation of sensory information, if an object is placed in only the left or only the right visual hemifield, then only the right or left hemisphere, respectively, of the split-brain patient will see it. Because language is very often localized in the left hemisphere, if we show the right hemisphere a picture and ask the patient what she saw, she will say she didn’t see anything
Which hemisphere is associated with language
left hemisphere
Gray matter
composed of the neuronal cell bodies. The cell bodies (or soma) contain the genes of the cell and are responsible for metabolism and synthesizing proteins
White matter
composed of the axons of the neurons, and, in particular, axons that are covered with a sheath of myelin
What is the result of the loss of gray and white matter
deficits in language, memory, reasoning, and other mental functions
Phrenology
Phrenologists assumed that various features of the brain, such as its uneven surface, are reflected on the skull; therefore, they attempted to correlate bumps and indentations of the skull with specific functions of the brain
Virtual dissection
Brain is imaged using computerized axial tomography or MRI scanners; they reveal with very high precision the various structures in the brain and can help detect changes in gray or white matter
These changes in the brain can then be correlated with behaviour, such as performance on memory tests, and, therefore, implicate specific brain areas in certain cognitive functions
Transcranial magnetic stimulation
refers to a technique whereby a brief magnetic pulse is applied to the head that temporarily induces a weak electrical current in the brain
Allows for very precise study of when events in the brain happen so it has a good temporal resolution, but its application is limited only to the surface of the cortex and cannot extend to deep areas of the brain
Transcranial direct current stimulation
uses electrical current directly, rather than inducing it with magnetic pulses, by placing small electrodes on the skull
Brain area is stimulated by a low current for a more extended period of time than TMS
When used in combination with cognitive training, tDCS has been shown to improve perfromance of many cognitive functions such as mathematical ability, memory, attention, and coordination
Neuroimaging tools
used to study the brain inaction; that is, when it is engaged in a specific task
Position emission tomography
records blood flow in the brain
PET scanner detects the radioactive substance that is injected into the bloodstream of the participant just before or while he or she is performing some task
detect the injected radioactive substance in specific brain regions, allowing researchers to infer that those areas were active during the task
Functional magnetic resonance imaging
relies on blood flow in the brain
Measures the changes in oxygen levels in the blood and does not require any substance to be injected into the participant
Electroencephalography
measures the electrical activity of the brain, and therefore, It has a much greater temporal resolution, depending on how it is used
More electrodes are used
Measure rather than produce activity
Any particular electrode can be coming from anywhere in the brain, EEG has poor spatial resolution; that is, we have only a rough idea of which part of the brain generates the measured activity
Diffuse optical imaging
can give researchers the best of both worlds: high spatial and temporal resolution, depending on how it is used
One shines infrared light into the brain, and measures the light that comes back out
Relies on the fact that the properties of the light change when it passes through oxygenated blood, or when it encounters active neurons
When DOI is set up to directly detect active neurons, it has both high spatial and temporal resolution
Psychophysiology
defined as any research in which the dependent variable is a physiological measure, and the independent variable is behavioural or mental
Physiological measures
take many forms and range from blood flow or neural activity in the brain to heart rate variability and eye movements
These measures can provide information about processes including emotion, cognition, and the interactions between them
Psychophysiological methods
a subset of the very large domain of neuroscience methods
Many neuroscience methods are invasive, such as involving lesions of neural tissue, injection of neutrally active chemicals, or manipulation of neural activity via electrical stimulation
Structural magnetic resonance imaging
a noninvasive technique that allows researchers and clinicians to view anatomical structures within a human. This image may be used to compare the size of structures in different groups of people or to increase the accuracy of spatial locations as measured with functional magnetic resonance imaging
Functional magnetic resonance imaging
a method that is used to assess changes in activity of tissue, such as measuring changes in neural activity in different areas of the brain during thought. Builds on the principles of sMRI and also uses the property that, when neurons fire, they use energy, which must be replenished
Process of functional magnetic resonance imaging
Glucose and oxygen, two key components for energy production, are supplied to the brain from the blood stream as needed
Oxygen is transported through the blood using hemoglobin, which contains binding sites for oxygen
When these sites are saturated with oxygen, it is referred to as oxygenated hemoglobin
When the oxygen molecules have all been released from a hemoglobin molecule, it is known as deoxygenated hemoglobin
Measures the change in the concentration of oxygenated hemoglobin, which is known as the blood-oxygen-level-dependent signal
electroencephalogram (EEG)
uses at least two and sometimes 256 electrodes to measure the difference in electrical charge between pairs of points on the head.
electrocortiography (ECoG)
typically used prior to medical procedures for localizing activity, such as the origin of epileptic seizures
Advange of EEG
its temporal resolution. Data can be recorded thousands of times per second, allowing researchers to document events that happen in less than a millisecond
Magnetioencephalography
Technique used for noninvasively measuring neural activity. Flow of electrical charged associated with neural activity produces very weak magnetic fields that can be detected by sensors placed near the participant’s scalp. Has same temporal resolution of EEG. Not susceptible to distortions from the skull and the scalp
Positron emission tomography (PET)
A medical imaging technique that is used to measure processes in the body, including the brain. Relies on a positron-emitting tracer atom that is introduced into the blood stream in a biologically active molecule, such as glucose, water, ammonia. Allows researchers to construct a three-dimensional image of the areas of the brain that have the highest metabolic needs, typically those that are more active
Transcranial magnetic stimulation
a noninvasive method that causes depolarization or hyperpolarization in neurons near the scalp. Not considered psychophysiological because the independent variable is physiological, rather than dependent. Qualifies as a neuroscience method because it deals with the function of the nervous system, and it can readily be combined with conventional psychophysiological methods. A coil of wire is placed above the participant’s scale and when electricity flows, it produces a magnetic field.
Peripheral nervous system
Includes skin conductance, cardiovascular responses, muscle activity, pupil diameter, eye blinks, and eye movements. All parts of the nervous system, excluding the brain and spinal cord; relays information between the CNS and other parts of the body
Central nervous system
the body’s coordinating centre for mechanical and chemical actions; made up of the brain and spinal cord
Sweat glands
Responsible for moisture and are controlled by the sympathetic nervous system
Cardiovascular measures
heart rate, heart rate variability, blood pressure
Electromyography
Measures electrical activity produced by skeletal muscles. Measures voltage between two points. Can be used to determine when a participant first initiates muscle activity to engage in a motor response to a stimulus or the degree to which a participant begins to engage in an incorrect response, even if it never visibly executed.
Advantage of structural MRI
High-resolution imaging, mon-invasive, multi-plane imaging, adaptability, longitudinal studies,
Disadvantages of structural MRI
High cost, time-consuming, motion sensitivity, noise and discomfort
Disadvantages of EEG
Low spatial resolution, susceptibility to noise, limited depth measurement, time consuming
Advantages of EEOG
High-spatial resolution, high temporal resolution, direct measurement
Disadvantages of EEOG
Invasive, High cost and specialized resources
Advantages of MEG
High temporal resolution, good spatial resolution, non-invasive, direct measurement,
Disadvantages of MEG
High cost, limited availability, motion sensitivity, complex data analysis
Advantages of PET
Provides detailed information about metabolic activity and physiological functions, capable of identifying abnormalities at the cellular level, measures metabolic activity quantitatively
Disadvantages of PET
Radiation exposure, high cost, limited spatial resolution, time-consuming
Advantages of TMS
Non-invasive, painless, allows precise stimulation of specific brain regions
Disadvantages of TMS
Limited depth stimulation, high cost, time-consuming, side effects
Development of the nervous system
During development, the nervous tissue emerges from ectoderm through the process of neural induction. This process causes the formation of the neural tube, which extends in a rostrocadual. As gestation progresses, the neural tube balloons up at the rostral end, and forebrain, midbrain, and the spinal cord can be visually delineated. The progenitor cells that form the lining of the neural tube generate all the neurons and glial cells of the central nervous system. During early stages of this development, neuroblasts rapidly divide and specialize into many varieties of neurons and glial cells. The neuroepithelium generates a group of specialized cells that migrate outside the neural tube to form the neural crest. This structure gives rise to sensory and autonomic neurons in the peripheral nervous system
ectoderm
The outermost layer of a developing fetus
Neural induction
A process that causes the formation of the neural tube
Rostrocaudal
a front-back plane used to identify anatomical structures in the body and the brain
Spina bifida
A developmental disease of the spinal cord, where the neural tube does not close caudally
Forebrain
a part of the nervous system that contains the cerebra hemispheres, thalamus, and hypothalamus
neuroblasts
Brain progenitor cells that asymmetrically divide into other neuroblasts or nerve cells
neuroepithelium
the lining of the neural tube
neural crest
a set of primordial neurons that migrate outside the neural tube and give rise to sensory and autonomic neurons in the peripheral nervous system
Autonomic nervous system
A part of the peripheral nervous system that connects to glands and smooth muscles. Consists of sympathetic and parasympathetic divisions
Somatic nervous system
A part of the peripheral nervous system that uses cranial and spinal nerves in volitional actions
Parasympathetic nervous system
a division of the autonomic nervous system that is slower than its counterpart- that is, the sympathetic nervous system- and works in opposition to it. Generally engaged in “rest and digest” functions
Sympathetic nervous system
a division of the autonomic nervous system, that is faster than its counterpart that is the parasympathetic nervous system and work in opposition to it. Generally engaged in “fight or flight” functions
Peripheral nervous system
Divided into somatic and autonomic nervous system
Central nervous system
Divided into a number of important parts, including the spinal cord, each specialized to perform a set of specific functions
Primary motor cortext
connects to the muscles of the body, and on volitional command moves them
cerebrum
Consists of left and right hemispheres that sit at the top of the nervous system and engages in a variety of higher-order functions
Sulcus
the crevices or fissures formed by convolutions in the brain
Gyrus
A buldge that is raised between or among fissures of the convoluted brain
Central sulcus
the major fissure that divides the fornal and parietal lobes
lateral sulcus
The major fissure hat delineates the temporal lobe below the frontal and parietal lobes
Primary motor cortex
A strip of cortex just in front of the central sulcus that is involved with motor control
Broca’s area
An area in the frontal lobe of the left hemisphere. Implicated in language production
Primary somatosensory cortex
A strip of cerebral tissue that just behind the central sulcus engaged in sensory reception of bodily sensations
Wernicke’s area
Involved with language comprehension and is connected to and Broca’s area through the arcuate fasciculus, nerve fibers that connect these two regions
Result of damage to the Wernicke’s area
many kinds of agnosia’s. Individual may show word deafness or word blindness
Agnosia
An inability to know or understand language and speech related behaviours
Frontal lobe
the most forward region of the cerebral hemispheres
parietal lobe
An area of the cerebrum just behind the central sulcus that is engaged with somatosensory and gustatory sensation
Occipital lobe
The back part of the cerebrum, which houses the visual ares
thalamus
a part of the diencephalon that works as a gateway for incoming and outgoing information
transduction
A process in which physical energy converts into neural energy
optic nerves
travel all the way to the thalamus and then to the visual cortex, where images that are received on the retina are projected
hypothalamus
Part of the diencephalon. Regulates biological drives with the pituitary gland. Plays a key role in regulating endocrine hormones in conjunction with the pituitary gland that extends from the hypothalamus through a stalk
Hindbrain
With the pons, processes sensory and motor information employing the cranial nerves, works as a bridge that connects to the cerebral cortex with the medulla, and reciprocally transfers information back and forth between the brain and the spinal cord
Pons
a bridge that connects the cerebral cortex with the medulla, and reciprocally transfers information back and forth between the brain and the spinal cord
Medulla oblongata
an area just above the spinal cord that processes breathing, digestion, heart and blood vessel function, swallowing, and sneezing
Cerebellum
A nervous system structure behind and below the cerebrum. Controls motor movement coordination, balance, equilibrium, and muscle tone
immunocytochemistry
A method of staining tissue including the brain, using antibodies
leison methods
a surgical method in which a part of the animal brain is removed to study its effects on behaviour or function
Computerized axial tomography
uses x-rays to capture many pictures of the brain and sandwiches them into 3-D models to study it. Resolution of this method is inferior to magnetic resonance imaging
MRI imaging
a way to capture brain images using large magnets that bobble hydrogen nuclei in the brain. They do not provide any functional information about the brain
Afferent nerves
Nerves that carry message to the brain or spinal cord
