Chapter 2: Research Methodology Flashcards
Scoville Scale
A measure of our detection of the amount of an ingredient called capsaicin in chili peppers
Capsaicin
The active ingredient in chili peppers that provides the experience of hotness, piquancy or spiciness
Psychophysical scale
A scale on which people rate their psychological experiences as a function of the level of a physical stimulus
Method of Limits
Stimuli are presented in a graduated scale, and participants must judge the stimuli along a certain property that goes up or down
Absolute threshold
The smallest amount of a stimulus necessary to allow an observer to detect its presence
Difference Threshold (JND)
The smallest difference between two stimuli that can be reliably detected
Ascending series
A series in which a stimulus gets increasingly larger along a physical dimension
Descending series
A series in which a stimulus gets increasingly smaller along a physical dimension
Crossover point
The point at which a person changes from detecting to not detecting a stimulus or vice versa
Two-point touch threshold
The minimum distance at which two touches are perceived as two touches and not one
Method of constant stimuli
A method whereby the threshold is determined by presenting the observer with a set of stimuli, some above threshold and some below it, in a random order
Method of adjustment
A method whereby the observer controls the level of the stimulus and “adjusts” it to be at the perceptual threshold
Point of subjectivity equality (PSE)
The settings of two stimuli at which the observer experiences them as identical
Sensitivity
The ability to perceive a particular stimulus; it is inversely related to threshold
Magnitude estimation
A psychological method in which participants judge and assign numerical estimates to the perceived strength of a stimulus
Response compression
As the strength of a stimulus increases, so does the perceptual response, but the perceptual response does not increase by as much as the stimulus increases
Steven’s power law
A mathematical formula that describes the relationship between stimulus intensity and our perception; it allows for both response compression and response expansion
Catch trial
A trial in which the stimulus is not presented
Forced-choice method
A psychophysical method in which a participant is required to report when or where a stimulus occurs instead of whether it was perceived
A method often used by researchers since it decreases the need for catch trials by having the participants be detailed with the responses they give.
Signal detection theory
The theory that in every sensory detection or discrimination, there is both sensory sensitivity to the stimulus and a criterion used to make a cognitive decision
False alarm
In signal detection analysis, a false alarm is an error that occurs when a nonsignal is mistaken for a target signal
Miss
In signal detection analysis, a miss is an error that occurs when an incoming signal is not detected
Correct rejection
In signal detection analysis, a correct rejection occurs when a nonsignal is dismissed as not present
Hit
In signal detection analysis, a hit occurs when a signal is detected when the signal is present
Criterion
A bias that can affect the rate of hits and false alarms.
Sensitivity (signal detection theory)
The ease or difficulty with which an observer can distinguish signal from noise
d’ (d prime)
A mathematical measure of sensitivity
Receiver-operating characteristic (ROC) curve
In signal detection theory, a plot of false alarms versus hits for any given sensitivity, indicating all possible outcomes for a given sensitivity
Electroencephalogrpahy (EEG)
Using electrodes to measure the electrical output of the brain by recording electric current at the scalp
Magnetoencephalography (MEG)
Using a magnetic sensor to detect the small magnetic fields produced by electrical activity in the brain
Transmagnetic stimulation (TMS)
A procedure in which a magnetic coil is used to stimulate electrically a specific region of the brain
Masking
Refers to the difficulty in seeing one stimulus when it is quickly replaced by a second stimulus that occupies the same or adjacent spatial locations
Sensorineural hearing loss
Permanent hearing loss caused by damage to the cochlea or auditory nerve or the primary auditory cortex
Conductive hearing loss
The inability of sound to be transmitted to the cochlea
Audiologist
A trained professional who specializes in diagnosing hearing impairments
Audiometer
A device that can present tones of different frequencies, from low in pitch to high in pitch, at different volumes from soft to loud
Audiogram
A graph that illustrates the thresholds for the frequencies as measured by the audiometer
Optometrist
A trained professional who specializes in diagnosing visual impairments and diseases
An example of “Response Expansion”
An example of response expansion is pain in the form of receiving electric shocks since the strength of the stimulus (electric shocks) increases the perceptual response (pain).
Kai has trouble reading the screen during class lectures. His optometrist is most likely to diagnose him with ______.
myopia
The limitation of ROC curves is that they can capture only one aspect of signal detection theory per graph. T/F
False
What is the purpose of a psychophysical scale?
to rate psychological experiences relative to physical experiences
What is the difference threshold?
the smallest detectable difference between two stimuli
EEG technology allows researchers to determine the time course of perceptual processes in the brain. T/F
True
What does an audiometer do?
It presents tones at different frequencies to assess hearing loss.
Approximately 15% of adults 65 years and older have some form of hearing impairment. T/F
False
Which neuroscience method is most appropriate for studying how the brain reacts to visual input?
fMRI
In masking studies, sensitivity is usually measured in terms of ______.
d’ analyses
A permanent hearing loss caused by damage to the cochlea or auditory nerve is known as ______ hearing loss.
sensorineural
Which of the following is a condition in which inadequate levels of sound reach the cochlea?
conductive hearing loss
