Review the Classical Psychophysical Methods for Measuring Thresholds of Perception, and Elaborate on the Improvements That Have Been Introduced in More Recent Times.
Review the classical psychophysical methods for measuring thresholds of perception, and elaborate on the improvements that have been introduced in more recent times.
The first psychological attribute to be measured was one of the most elementary concepts within the psychological domain… sensitivity. The sensations we distinguish are not always stimulated by our senses alone, so scientists wanted to develop a way to link together both the physical happenings of the world with the subjective experiences of ones mind. The techniques used to investigate this relationship between psychological sensations and physical stimuli are referred to as ‘psychophysics’. Psychophysics consists of various methods used within an experiment to look at a specific perceptual system. In 1866, physicist and philosopher Gustav Theodor Fechner published his paper ‘Elements of Psychophysics’ which led to the conceptualisation of the term psychophysics. Fechner was inspired by the work of physiologist Ernest Heinrich Weber’s (1830).
Both Fechner and Weber pioneered the conceptual framework for methods of classical psychophysics, which primarily aim to discover a threshold for sensitivity. A threshold is defined as the amount of stimulation needed for an observer to become aware of the stimulus. The classical methods of psychophysics are used to estimate two types of threshold: the absolute threshold and the difference threshold (also known as the just noticeable difference or JND).
The absolute threshold is defined, as the minimum intensity a stimulus must produce in order to create a sensation detectable to an observer. Any stimulus intensity that is below this threshold will not generate the level of neural activation required for an observer to perceive the stimuli. As reactions to stimuli can vary, the threshold value is determined by the stimulus intensity that is apparent 50% of trials.
On the other hand, the minimal intensity difference needed for an observer to distinguish...