Sensation and perception Flashcards
A topic can be understood by studying it at a number of different levels of a system.
levels of analysis
Physiological levels of analysis.
levels ranging from chemical reactions to single neurons, to structures in the brain, to groups of structures in the brain.
proposed that signals could be transmitted throughout the net in all directions.
Nerve net theory
Cell that is specialized to receive and transmit information in the nervous system.
neurons
A network of continuously interconnected nerve fibers (as contrasted with neural networks, in which fibers are connected by synapses).
Nerve net
The idea that individual cells called neurons transmit signals in the nervous system, and that these cells are not continuous with other cells as proposed by nerve net theory.
neuron doctrine
Part of a cell that contains mechanisms that keep the cell alive. In some neurons, the cell body and the dendrites associated with it receive information from other neurons.
cell body
Structures that branch out from the cell body to receive electrical signals from other neurons.
Dendrites
Part of the neuron that transmits signals from the cell body to the synapse at the end of the axon.
Axons
Space between the end of an axon and the cell body or dendrite of the next axon.
Synapse
Group of interconnected neurons that are responsible for neural processing.
neural circuits
Specialized neural structures that respond to environmental stimuli such as light, mechanical stimulation, or chemical stimuli.
Receptors
What did Edgar Adrian win the Nobel prize for in 1932?
recorded electrical signals from single sensory neurons-Adrian recorded electrical signals from single neurons using microelectrodes—small shafts of hollow glass filled with a conductive salt solution that can pick up electrical signals at the electrode tip and conduct these signals back to a recording device. Modern physiologists use metal microelectrodes.
Difference in charge between the inside and outside of a nerve fiber when the fiber is at rest (no other electrical signals are present).
Resting potentail
An electrical response that is propagated down the length of an axon (nerve fiber). Also called an Action potential.
nerve impulse
Propagated electrical potential responsible for transmitting neural information and for communication between neurons. Action potentials typically travel down a neuron’s axon.
action potential
adrian studied the relation between nerve firing and sensory experience by
measuring how the firing of a neuron from a receptor in the skin changed as he applied more pressure to the skin. What he found was that the shape and height of the action potential remained the same as he increased the pressure, but the rate of nerve firing—that is, the number of action potentials that traveled down the axon per second—increased
Point at which we can detect a stimuli more than 50% of the time.
Absolute threshold
Absolute threshold is absolute?
False
Measurement of the minimum difference needed between stimuli variables to be perceptivle. “just perceptible difference” (less than 50%
Difference threshold.
Determines perceptible diffeneces in sensation
Weber’s law
Visual information is processed______in the brain
Cross-hemispherically
What are the two types of receptors in the eye?
Rods and cones
Two visual pathways
Parvocellular and Magnocelluar
what are the limits of our sensation?
Types of energy we can sense and elements of energy we can sense.
Information which falls blow the absolute threshold is considered what?
Subliminal
