What is true of signal-detection theory?

A) Signal-detection theory allows one to separate actual perceptual ability from response tendencies.
B) Signal-detection theory suggests that, for each participant, there exists a constant stimulus intensity corresponding to a zero stimulus.
C) Signal-detection theory suggests that perceived sensation occurs only in the presence of an external stimulus.
D) Signal-detection theory suggests that confusion about whether or not a stimulus has been presented is most likely to occur when the signal is much greater than the noise.

Signal-detection theory allows one to separate actual perceptual ability from response tendencies. It suggests that a participant's response to a stimulus is influenced not only by their perceptual ability but also by factors such as their personal bias and the context in which the stimulus occurs. By separating these two factors, signal-detection theory provides a more accurate assessment of a participant's perceptual ability.

Answer: B
Signal-detection theory suggests that, for each participant, there exists a constant stimulus intensity corresponding to a zero stimulus. This is known as the participant's "noise level" and represents the amount of random neural activity occurring in the absence of any external stimulus. This noise level can vary between individuals and affects their ability to detect a stimulus amidst background noise.

Answer: C
This statement is false. Signal-detection theory suggests that perceived sensation can occur in the absence of an external stimulus, as a result of internal neural activity.

Answer: D
This statement is false. Confusion about whether or not a stimulus has been presented is most likely to occur when the signal is weak and similar in intensity to the noise, making it difficult to distinguish from background noise. When the signal is much greater than the noise, it is more likely to be detected and correctly identified as a stimulus.