Chapter 1: Introduction Flashcards
(23 cards)
the ability to detect a stimulus and, perhaps, to turn that detection into a private experience
sensation
the act of giving meaning to a detected sensation
perception
physical matter is the only reality
materialism
the smallest detectable difference between two stimuli, or the minimum change in a stimulus that enables it to be correctly judged as different from a reference stimulus
just noticeable difference (JND) /// difference threshold
describes the relationship between stimulus and its sensation that says the just noticeable difference (JND) is a constant fraction of how strong the stimulus is
Weber’s Law
describes the relationship between stimulus and sensation that says the magnitude of the sensation increases proportionally to the logarithm of the stimulus intensity
Fechner’s law
the minimum amount of stimulation necessary for a person to detect a stimulus 50% of the time
absolute threshold
a random presentation of many different stimuli ranging from almost always perceivable to very rarely perceivable one at a time and then you’re going to see if your subject at each level experienced the stimuli or not, participants respond to each presentation: “yes/no,” “same/different,” and so on.
method of constant stimuli
a method of limits in which the participant controls the change in the stimulus until it matches some particular criterion
method of adjustment
a psychophysical method in which the participant assigns values according to perceived magnitudes of the stimuli (ex. going to the doctor and they ask you what your pain level is from 1-10, you assign some magnitude to your experience)
magnitude estimation
describes the relationship between stimulus and the sensation that says the magnitude of a sensation is proportional to the stimulus magnitude raised to an exponent
Steven’s power law
the ability to match the intensities of sensations that come from different sensory modalities. this ability allows insight into sensory differences. for example, a listener might adjust the brightness of a light until it matches the loudness of a tone
cross-modality matching
a psychophysical theory that quantifies the response of an observer to the presentation of a signal in the presence of noise. measures obtained from a series of presentations are sensitivity (d”) and criterion of the observer
signal detection theory
an internal threshold that is set by the observer (the self)
if the internal response is above criterion, the observer gives one response (e.g., “yes, I hear that”). below criterion, the observer gives another response (e.g., “no, I hear nothing).
criterion
a value that defines the ease with which an observer can tell the difference between the presence and absence of a stimulus or the difference between Stimulus 1 and Stimulus 2.
sensitivity
a mathematical procedure by which any signal can be separated into component sine waves at different frequencies. combining these sine waves will reproduce the original signal.
Fourier analysis
the number of cycles of a grating (e.g., changes in light and dark) per unit of visual angle (usually specified in cycles per degree).
spatial frequency
a doctrine, formulated by Johannes Müller, stating that the nature of a sensation depends on which sensory fibers are stimulated, rather than how they are stimulated.
doctrine of specific nerve energies
the junction between neurons that permits information transfer
synapse
a chemical substance used in neuronal communication at synapses
neurotransmitter
the skull cap of electrodes that measures electrical activity of the neurons at the brain
EEG
a variant of magnetic resonance imaging that makes it possible to measure localized patterns of activity in the brain. activated neurons provoke increased blood flow, which can be quantified by measuring changes in the response of oxygenated and deoxygenated blood to strong magnetic fields
functional magnetic resonance imaging (fMRI)
the science of defining quantitative relationships between the physical and psychological events
psychophysics
