Brain And Behaviour - Ch 4 Flashcards
Neurons
Basic building blocks of the nervous system
Dendrites
Specialized receiving units like antennae that collect messages from neighboring neurons and send them on to the cell body
Axon
Conducts electrical impulses away from the cell body to other neurons, muscles or glands
Glial cells
Cells surrounding neurons keeping them in place
Providing nutrients neurons need
Isolating toxins that would harm the neuron
Resting potential
Internal difference of around 70 millivolts
Action potential
Electrical shift which lasts about a millisecond
Absolute refractory period
Period during which the membrane is not excitable and cannot discharge another impulse
All-or-none law
Action potentials occur at a uniform and maximum intensity or they do not occur at all
Myelin sheath
A whitish, fatty insulation layer derived from glial cells during development.
Somatic nervous system
Sensory neurons that are specialized to transmit messages from sensory receptions and motor neurons that send messages from the brain and spinal chord to the muscles that control our voluntary movements
Autonomic nervous system
Senses the body’s internal functions and controls the glands and the involuntary muscles that form the heart, the blood vessels, and the lining of the stomach and intestines.
Sympathetic nervous system
Has an activation or arousal function.
Parasympathetic nervous system
Slows down body processes and maintains a state of tranquility.
Central nervous system
Contains the brain and the spinal chord which connects most parts of the peripheral nervous stet with the brain
Electroencephalogram (EEG)
Measures the activity of a large group of neurons through a series do large electrodes placed on the scalp.
Computerized axial tomography (CT)
Uses X-ray technology to study brain structures
Magnetic resonance imaging (MRI)
Creates images based on how atoms in living tissue respond to a magnetic pulse delivered by the device.
Positron-emission tomography (PET scans)
Measures brain activity including metabolism, blood flow and neurotransmitter activity.
Functional MRI (fMRI)
Can produce pictures of blood flow in the brain taken less than a second apart
Near infra-red spectroscopy (NIR)
Measures brain activity in terms of oxygen use using radiation close to the infra-red region.
Transcranial magnetic stimulation. (TMS)
Disruption of a targeted part of the brain with a magnetic coil.
Vascular brain damage
Disruption to blood flow to the brain due to a blockage (stroke), partial blockage (ischemia) or an enlarged artery (aneurysm).