Slide 1: Understanding Sensory Thresholds
Background:
In the field of psychology and sensory perception, we often talk about thresholds that determine how we detect and respond to stimuli in our environment. Two important concepts are absolute threshold and difference threshold. Understanding these terms helps us comprehend how our brains process sensory information and how we experience the world around us.
Vocabulary:
- Absolute Threshold: The smallest amount of stimulus that can be detected by our senses (e.g., sight, sound, touch).
- Difference Threshold: The smallest change in a stimulus that can be detected when comparing two stimuli. It is also known as the "just noticeable difference" (JND).
Slide 2: Key Differences
Absolute Threshold
- Definition: The minimum intensity of a stimulus that can be detected 50% of the time. For example, the faintest sound a human can hear or the lowest light level needed to see something in the dark.
- Example: A candle flame can be seen from 30 miles away on a clear night.
Difference Threshold
- Definition: The minimum difference in intensity between two stimuli that allows them to be perceived as different. This is not a fixed amount; it's proportional to the initial intensity of the stimulus.
- Example: If you were holding a small weight and an additional 2-ounce weight is added, you might not notice the change. However, if you were holding a 10-pound weight and an additional 2-ounce weight is added, you would likely feel the difference.
Conclusion:
In summary, the absolute threshold refers to the smallest level of stimulus that can be sensed, while the difference threshold refers to the smallest change in that stimulus which can be detected when compared to another. Both concepts help illustrate how we interact with our sensory environment, showcasing the limits and capabilities of human perception.