Bell Ringer 1. What is sensation? List 5 examples. 2. What is perception?

Sensation and Perception The Biological Basis of Behavior: Unit III

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4.1 Sensation and Perception: The Basics Sensation The stimulation of sensory receptors and the transmission of sensory info to the CNS. Occurs anytime a stimulus activates one of the receptors in your sense organs

What if we could sense everything? Life would hurt… so we can only take in a window of what is out there.

Perception The process through which we interpret sensory stimulation. Organizing and interpreting information, enabling us to recognize meaningful objects and events Two types Preattentive – method of extracting information automatically when presented with stimuli. Attentive – not automatic

Stroop effect – preattentive process as an interference Don't read the words -just say the colors they're printed in, and do this aloud as fast as you can.

Perception (contd.) Perception reflects learning, expectations, and attitudes. Perception reflects your experiences.

4 Concepts that affect sensation and perception 1.Absolute Threshold 2.Difference Threshold 3.Signal-detection theory 4.Sensory adaptation

1. Absolute Threshold The weakest amount of a stimulus that can be sensed. Dogs vs. humans mice vs. owls Absolute threshold can differ from person to person. Differences stem from psychological and biological factors.

2. Difference Threshold The minimum amount of difference that can be detected between two stimuli. People’s individual difference thresholds vary slightly. Is it midnight blue or black?

3. Signal-Detection Theory A method of distinguishing sensory stimuli that takes into account not only their strengths but also… the setting your physical state your mood and your attitudes We focus on whatever we consider important Considers motivations, expectations, and learning Child’s performance at school/sport

4. Sensory Adaptation The process by which we become more sensitive to weak stimuli and less sensitive to unchanging stimuli. Movie theater The beach Traffic vs. crickets Smelly bathroom