Sensory methods Flashcards
What are three classical psychological data collection methods?
Method of adjustment
Method of limits
Method of constant stimuli w
What is the method of adjustment?
Let the subject adjust the stimulus intensity until the target is just
discernible; Subject has control over the stimulus
What is the method of limit?
Present stimulus in one
direction until the subject
achieves reliable
response patterns, Ascending and
descending alternating,Can have different
arrangements
What is the method of constant stimuli?
Randomly present each stimulus
∎For auditory research, each stimulus is
presented for >100 times
∎Subject indicate whether it was the target or
not
What are some examples of test arrangements?
Yes-No task
∎2-Alternativa forced choice task
∎3 or n-Alternative forced choice task
∎Same-Different task
What is the forced choice method?
Participants demonstrate that they do detect the stimulus by identifying some alternative features.
E.g Sound is presented as a stimulus, you have to tell whethere this stimulus comes from left or right.
Can use with signal detection theory to get a stronger objective measurement
What are these test arrangements used in combination with?
The Three Classic Methods.
Shall we determine the threshold as soon as the participant detects it once?
No, because Perceptual strength of a same stimulus varies following a Gaussian
distribution
How is the correctness of a participant’s responses recorded in olfactory studies?
It is recorded at each concentration and converted into a percentage.
What is the term for the smallest detectable difference in odor concentration?
The threshold or just noticeable difference (JND
What is the definition of JND?
Change in stimulus required to elicit a change in sensation
What is the formula for calculating P(c) (probability of correct responses)?
P(c) = Correct trials / Total chances (guesses).
If you were given 100 pairs of guesses and guessed correctly in 60 trials, what is P(c)?
P(c) = 60/100 = 0.6.
How is sensitivity determined in applied sensory science?
Based on P(c) (probability of correct responses).
Where is the criterion for sensitivity usually set?
Halfway between chance and perfect performance.
What is Signal Detection Theory (SDT)?
A framework used to quantify how people make decisions under uncertainty.
What two factors does SDT distinguish between?
Observer’s sensitivity to a stimulus and their decision-making criteria.
In which fields is SDT especially useful?
Psychophysics, perception research, and cognitive psychology.
Does Signal Detection Theory (SDT) use thresholds?
No, it uses d’ (dee-prime) as a sensitivity measure.
What is the sensitivity measure in SDT?
DEE Prime
What is the response criterion?
Subject judges the stimulus using a response criterion
Where shall we put our
response criterion?
In the middle
Does response criterion
affect d-prime?
No, since the d-prime is sensitivity, and separate thing from response bias.
What are the advantages of SDT?
Recognise perceptual variation, pure sensitivity measure, and enable measurements of response bias.
What is a cross-modal sensory interaction?
When the function of one sense is changed by stimulation of another sense.
What functions can be affected in a cross-modal sensory interaction?
Sensitivity, perceived intensity, or other measures of responsiveness.
What did McGurk and MacDonald (1976) demonstrate?
Visual information can strongly influence what we hear in speech perception.
Is auditory information the only source for speech perception?
No, visual information also plays a crucial role.
What is the term for the interaction between auditory and visual cues in speech perception?
Audiovisual speech perception.
what are the three most common cross modal sensory interactions across chemosensory senses?
Taste-odour
Colour-flavour(vision and flavour)
Chemesthesis – flavour
What are the three not cross-modal
sensory interactions?
Temperature(Change the vapour pressure and partition coefficients
of volatile compounds and therefore their release
from a solute. )
Viscosity(Influence partition coefficients of volatile compounds
and availability of compounds for perception. )
Fat content(Influences the physical property of a food matrix, so
changing its flavour significantly)
How can specific taste qualities be affected by odors?
They can be enhanced in the presence of complementary odors.
What happens when taste and odor compounds with complementary characteristics are combined?
The perceived intensity of the combination is stronger than when either is presented alone.
What is the example of taste-odour interaction?
Sweet, vanilla together could enhance the perception
What can happen when a below-threshold tastant and a below-threshold odorant are combined?
They can create an above-threshold flavor perception.
What is an example of a below-threshold odor-taste pairing?
Benzaldehyde (almond-like odor) + Saccharin (sweet taste).
Does the effect of odor-taste interactions depend on the specific pairing?
Yes, different odor-taste combinations produce different effects.
What study explored the effect of sweeteners on fruitiness perception?
Wiseman and McDaniel (1989) studied Aspartame vs. Sucrose on fruitiness.
When is an odor-taste interaction more likely to occur?
When the odor and taste have been previously experienced together.
How does familiarity affect odor-taste interactions?
Familiar tastant-odorant pairs yield stronger effects.
How does congruency influence taste intensity?
Taste intensity is enhanced for congruent mixtures (e.g., sucrose-strawberry, sucrose-lemon) but not for incongruent mixtures (e.g., sucrose-mushroom).
Which study examined the role of congruency in taste perception?
Schifferstein and Verlegh (1996).
How does color (appearance) affect flavor perception?
Color has a strong influence on how flavors are perceived.
What aspects of flavor perception are influenced by color?
Absolute threshold measures, identification, and discrimination of flavor.
What is the study studied by Blackwell.L
people are more likely to identify correctly the fruit odours in the appropriate coloured solution than in the inapporiate color
What experimental setting was used to study the effect of lighting on taste perception?
A restaurant setting with different lighting conditions.
What was the structure of the experiment?
A 4-course dinner with varying taste qualities and textures.
How did bright lighting affect taste perception?
It enhanced overall taste intensity.
Did lighting affect the pleasantness of food?
No, lighting had no effect on food pleasantness.
What is synaesthesia?
A perceptual phenomenon where stimulation of one sensory or cognitive pathway triggers involuntary experiences in another sensory or cognitive pathway.
What are some common types of synaesthesia?
Grapheme-color (letters/numbers appear in colors)
Taste-shapes (tastes evoke shapes)
Word-taste (words trigger specific tastes)
Personification (numbers/letters have personalities)
Color-sound (sounds trigger color experiences)
What is thermal taster status?
A taste phenotype where a thermally-induced taste sensation occurs when the tongue is stimulated by temperature alone, without a gustatory stimulus.
When was thermal taster status first reported?
In 2000.
What percentage of people are affected by thermal taster status?
At least 25%.
What does the researcher suggest from the study of the neural correlates of cross modal binding ?
It happens in the multimodal areas, there is competitive relationship between multimodal and unimodal.
What does the researcher suggest from the study of the viewing images of food evokes taste quality specific activity in gustatory insular cortex?
Insular gets activated, unimodal area plays the key role as well
