Psych 104 - Chapter 4

The perceptual experience of one sense that is evoked by another sense.

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Simple awareness due to the stimulation of a sense organ

Organization, identification, and interpretation of a sensation in order to form a mental representation

When many sensors in the body convert physical signals from the environment into neural signals sent to the central nervous system

Physical energy from the world to neural energy in the CNS

To find a reliable way to measure something

Structuralist

Structuralist

Wilhelm Wundt and Edward Titchener

Gustav Fechner

Methods that measure the strength of a stimulus and the observer's sensitivity to that stimulus

The minimal intensity needed to just barely detect a stimulus

Intensity of the stimulus at which an observer can detect it on 50% of the trials

• Gustav Fechner
• Just noticeable difference (JND)
• The minimal change in a stimulus that can just barely be detected

A fixed intensity

The just noticeable difference is roughly proportional to the magnitude of the standard stimulus - 1834

The just noticeable difference of a stimulus is a constant proportion despite variations in intensity

Gustav Fechner created it, influenced by Ernst Weber

The response to a stimulus depends on: 1. A person's sensitivity to the stimulus, and 2. A person's response criterion

Liberal - tend to say they detect a signal vs. conservative - tend to say they don't detect a signal

Gustav Fechner in 1860 - characteristics of the stimulus and the observer need to be taken into account

How effectively the perceptual system represents sensory events

Sensitivity to prolonged stimulation tends to decline over time (organism adapts)