Sensation & Perception | AP Psychology

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the difference between sensation and perception?

Sensation is the receiving of stimuli from the outside environment, whereas perception is the organizing and interpreting of sensory information.

What is absolute threshold?

The minimum stimulation needed to detect a particular stimulus 50% of the time.

What is the difference threshold?

The minimum difference between two stimuli required for detection 50% of the time.

What is Weber's Law?

The principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage. Signup and view all the answers

What is sensory adaptation?

Diminished sensitivity as a consequence of constant stimulation. Signup and view all the answers

Why is sensory adaptation useful?

It allows freedom to focus on informative changes in our environment without being distracted by background stimuli. Signup and view all the answers

What does sensory adaptation have to do with the movements of the eye?

Our eyes are always moving, ensuring that stimulation on the eyes' receptors continually changes. Signup and view all the answers

What happens during visual stimulation?

Our eyes receive light energy and transduce it into neural messages that our brain processes. Signup and view all the answers

What is stimulus input in relation to color perception?

Pulses of electromagnetic energy that our visual system perceives as color. Signup and view all the answers

What are rods?

Retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision. Signup and view all the answers

What are cones?

Retinal receptor cells that function in daylight and detect fine detail and color sensations. Signup and view all the answers

What are bipolar cells?

Specialized cells that connect rods and cones to the ganglion cells of the optic nerve. Signup and view all the answers

What are ganglion cells?

Specialized cells that lie behind the bipolar cells and whose axons form the optic nerve. Signup and view all the answers

What is a blind spot?

The point at which the optic nerve leaves the eye, creating a 'blind' spot. Signup and view all the answers

What is the Young-Helmholtz Theory?

The theory that the retina contains three different color receptors sensitive to red, green, and blue. Signup and view all the answers

What is the Opponent-Process Theory?

The theory that opposing retinal processes enable color vision. Signup and view all the answers

What is an afterimage?

Sensations that linger after the stimulus is removed, often appearing in reversed colors. Signup and view all the answers

What is color constancy?

Perceiving familiar objects as having consistent color even if changing illumination alters the wavelengths reflected. Signup and view all the answers

How is the process of perception affected by selective attention?

Our senses detect energy from the environment, which is then perceived meaningfully aided by knowledge and expectations. Signup and view all the answers

Study Notes

Sensation vs. Perception

Sensation is the reception of external stimuli; perception is the organization and interpretation of that sensory information.

Absolute Threshold

Defined as the minimum stimulation required to detect a stimulus 50% of the time.
Example: Requires at least 2 inches of cut for noticeable change in shirt length.

Difference Threshold

The minimum difference between two stimuli necessary for detection 50% of the time, referred to as the just noticeable difference (jnd).

Weber's Law

States that to differentiate two stimuli, they must differ by a constant minimum percentage, not a constant amount.

Sensory Adaptation

Diminished sensitivity to constant stimulation due to decreased nerve cell firing frequency over time.

Benefits of Sensory Adaptation

Allows focus on changing stimuli in the environment, filtering out constant background noise.
Example: Individuals may not notice their own scent due to adaptation.

Eye Movements and Sensory Adaptation

Continuous eye movements ensure stimulation on the eyes' receptors changes, preventing sensory adaptation to visuals.

Visual Stimulation

Eyes convert light energy into neural messages for the brain to process as conscious sight.

Stimulus Input

Perception of color (e.g., red) arises from electromagnetic energy, not the color itself.
Visible light represents only a small part of the entire electromagnetic spectrum.

Rods

Retinal receptors responsible for detecting shades of black, white, and gray, critical for peripheral and dim-light vision.

Cones

Retinal receptors functioning optimally in well-lit conditions, allowing for color perception and fine detail detection.

Bipolar Cells

Specialized cells connecting rods and cones to the ganglion cells of the optic nerve.

Ganglion Cells

Cells located behind bipolar cells; their axons create the optic nerve that transmits visual information to the brain.

Blind Spot

The area where the optic nerve exits the eye contains no receptor cells, resulting in a visual gap.

Young-Helmholtz Theory

Proposes three types of color receptors in the retina (red, green, blue) that combine to create the perception of any color.

Opponent-Process Theory

Suggests color vision results from opposing retinal processes (red-green, yellow-blue, white-black) that allow for color differentiation.

Afterimage

Visual sensations that persist after the stimulus is removed; common visual afterimages are often in inverted colors.

Color Constancy

The ability to perceive familiar objects as maintaining consistent color, despite illumination changes altering reflected wavelengths.

Selective Attention in Perception

Relates to the process where the brain focuses on specific stimuli while filtering out others, influenced by knowledge and expectations, shaping overall perception.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on the key concepts of sensation and perception in this AP Psychology quiz. Understand the distinctions between sensation and perception, as well as grasp the foundational principle of absolute threshold. Perfect for students preparing for the AP exam.