Chapter 2&3/ Week 3 Flashcards
The interaction of the signals of many neurons
Neural processing
Where electrical signals take place
Neurons
Contains mechanisms to keep the cell alive
Cell body
Branch out from the cell body to receive electrical signals from other neurons
Dendrites
A.k.a. nerve fiber, which is filled with fluid that conducts electrical signals
Axon
The value which stays roughly, the same, as long as there are no signals in the neuron
Resting potential
The signal identified by the predictable rise and fall of the charge inside the axon relative to the outside and last about 1 ms
Action potential
Once the response triggered It travels all the way down the axon without decreasing in size.
Propagated response
The interval between the time one nerve impulse occurs in the next one can be generated in the axon
Refractory Period
Action potentials that occurred in the absence of stimuli from the environment
Spontaneous activity
Molecules that carry an electric charge
Ions
Refers to the ease with which a molecule can pass through the membrane
Permeability
An increase in positive charge inside the neuron
Depolarization
The quick and steep depolarization from -70 mV to positive 40 mV during an action potential
Rising phase of the action potential
An increase in negative charge inside the neuron
Hyperpolarization
The hyperpolarization from +40 mV back to -70 mV
Falling phase of the action potential
The small space between neurons
Synapse
When action potential reach the end of a neuron, they triggers the release of this chemical
Neurotransmitters
The structures in which Neuro transmitters are stored
Synaptic vesicles
The neurotransmitter molecules flow into the synapse to small areas on the receiving neuron, which are called…
Receptor sites
A response that occurs when the neuron becomes depolarized, and the inside of the neuron becomes more positive
Excitatory response
A response that occurs when the inside of the neuron becomes more negative or hyperpolarized
Inhibitory response
A code that refers to how neurons represent various characteristics of the environment
Sensory coding
A specialize neuron that respond only to one concept or stimulus
Specificity coding
Highly specific type of neuron
Grandmother cell
A particular stimulus is represented by a pattern of firing of only a small group of neurons, with the majority of neurons remaining silent
Sparse coding
Proposes that our experiences are represented by the pattern of firing across a large number of neurons
Population coding
Gall concluded that there were about 35 different mental faculties that could be mapped onto different brain areas based on the bumps and contours on the person skull
Phrenology
The idea that specific brain areas are specialized to respond to specific type of stimuli or functions
Modularity
Speech production area
Broca’s area
Area in the temporal lobe involved in understanding speech
Wernicke’s area
A field of study relating the location of brain damage to specific affects on behavior
Neuropsychology
A more controlled way that modularity has been studied is by recording brain responses in neurologically normal humans which makes it possible to create pictures of the location of the brain’s activity
Brain imaging
Proposes that the brain represents information and patterns, distributed across the cortex rather than one single brain area
Distributed representation
The roadmap of fibers, connecting different areas of the brain
Structural connectivity
The neural activity associated with a particular function that is flowing through the structural network
Functional connectivity
Recording an fMRI as a person is engaged in a specific tasks, such as listening to certain sounds
Task related fMRI
Recording an fMRI, when the brain is not involved in a specific task
Resting state fMRI
The determined brain location associated with carrying out a specific task
Seed location
The other location where resting state is measured
Test location
How do physical processes like nerve impulses become transformed into the richness of perceptual experience?
The mind body problem
The distance between the peaks of the electromagnetic waves
Wavelength
The energy within the electromagnetic spectrum that humans can perceive
Visible light
Where light enters the eye through
Pupil
Allows light to enter the inside of the eye
Cornea
Transmits light to the retina
Lens
The network of neurons that cover the back of the eye
Retina
Converts light into signals that are sent to the brain
Photoreceptors
A type of photo receptor shaped like a rod, allows for peripheral vision
Rods
A type a photo receptor, helps us to see fine detail
Cones
Light-sensitive chemicals that react to light and trigger electrical signals
Visual pigments
A bundle of more than 1 million nerve fibers that carry visual messages
Optic nerve
A small center of the eye where visual acuity is the highest, retinal cones are particularly concentrated here
Fovea
An area that includes all of the outside of the fovea, containing both rods and cones. Responsible for our side, and night vision.
Peripheral retina
Most common in older people, destroys the cone-rich fovea, and a small area that surrounds it
Macular degeneration
Degeneration of the retina that is passed from one generation to the next. This condition first attacks, the peripheral rod, receptors and results in poor vision in the peripheral visual field.
Retinitis pigmentosa
The area of the eye where there is an absence a photoreceptors
Blindspot
A muscle that increases the focusing power of the lens by increasing its curvature
Ciliary muscles
The change in the lens shape that occurs when the ciliary muscles at the front of the eye tighten, and increase the curvature of the lens, so that it gets thicker
Accommodation
A number of errors that can affect the ability of the cornea and/or lens to focus the visual input into the retina
Refractive errors
Age related loss of the ability to accommodate. Can be dealt with by wearing reading glasses, which brings near objects into focus by replacing the focusing power that can no longer be provided by the lens.
Presbyopia
The inability to see distant objects clearly
Myopia/nearsightedness
A condition in which the cornea/lens bends the light too much
Refractive myopia
A condition in which the eyeball is too long
Axial myopia
The inability to see nearby objects clearly. Usually happens because the eyeball is too short.
Hyperopia/farsightedness
The transformation of one form of energy into another form of energy
Transduction
A process that creates a chemical chain reaction that activates thousands of charged molecules to create electrical signals in receptors
Isomerization
Increasing sensitivity in the dark
Dark adaptation
What is used to measure the increase sensitivity in the dark
Dark adaptation curve
The sensitivity measure in the light
Light adapted sensitivity
The sensitivity at the end of dark adaptation, about 100,000 times greater than the light adaptive sensitivity measured before dark adaptation began
Dark adapted sensitivity
People who have no cones because of a rare genetic defect. Provide ways to study rod, dark adaptation without interference from cones.
Rod monochromats
The place where the rods begin to determine the dark adaptation curve instead of the cones
Rod-cone break
The change in shape and separation from the opsin that causes molecules to become lighter in color
Visual pigment bleaching
In order to do their job of changing light energy into electrical energy, the retinal needs to return to its bent shape and become attached to the opsin
Visual pigment regeneration
The eye’s sensitivity to light as a function of the lights wavelength
Spectral sensitivity
The light of a single wave length created, using special filters or device called a spectrometer
Monochromatic light
The enhanced perception of short wave lengths during dark adaptation
Purkinje shift
A plot of the amount of light absorbed versus the wavelength of the light
Absorption spectrum
Interconnected groups of neurons within the retina
Neural circuits
Occurs when the number of neurons synapse onto a single neuron
Neural convergence
The region of the retina that must receive illumination in order to obtain a response in any given fiber
Receptive field
In these receptive fields, the area in the “center” of the receptive field response differently to life than the area in the “surround” of the receptive field
Center-surround receptive fields
The area that increases neuronal firing when a stimulus is presented towards the area
Excitatory area
The area that decreases firing when a stimulus is presented toward the area
Inhibitory area
The receptive field, which responds with excitation, when the center is stimulated, and an inhibition, when the surround is stimulated
Excitatory-Center, inhibitory-surround receptive field
The receptive field, which response within inhibition, when the center is stimulated and excitation, when the surround is stimulated
Inhibitory-Center, excitatory-surround receptive field
A small spot of light presented to the excitatory center of the receptive field, causes a small increase in the rate of nerve firing; increasing the light size so that it covers the entire center of the receptive field, increases the cells response
Center-surround antagonism
The inhibition involved in Center-surround ganglion cell receptive fields, inhibition that is transmitted across the retina (laterally)
Lateral inhibition
An increase in perceived contrast at borders between regions of the visual field
Edge enhancement
The perceived light and dark bands at the borders, which are not present in the actual physical stimuli
Chevruel illusion
Light and dark bands created at fuzzy borders
Mach bands
