Sensation and Perception Chapter Quiz

Sensation and Perception

• Knowledge originates from perceptions.
• Sensation involves detecting, converting, and transmitting sensory information from receptors to the brain.
• Perception involves assembling sensory input into meaningful patterns in the brain. Perceptions are personal interpretations of the world.
• Psychophysics studies the relationship between physical stimuli and sensations.
• Transduction converts physical energy (sound, light, pressure) into neural signals.

Sensation Thresholds

• Absolute threshold is the minimum stimulation needed to detect a stimulus 50% of the time.
• Just Noticeable Difference (JND) is the minimum difference between two stimuli detectable 50% of the time.
• Weber's Law: JND is a constant proportion of the original stimulus, not a constant amount.
• Signal Detection Theory predicts how/when we detect a signal against background noise. Thresholds vary between people and are not absolute.

Somesthetic Senses

• Somesthetic senses include vestibular (balance), kinesthetic (body position/movement), and touch (pressure, warmth, cold, pain).
• Kinesthesis senses position and movement; Vestibular senses balance and position relative to gravity. Semicircular canals filled with fluid sense head motion.

Body Position and Movement

• Vestibular system relates to balance. Motion sickness results from sensory conflict (between vestibular, visual, and body sensations).

Vision and Hearing

• Audition (hearing) transduces air pressure waves into neural impulses. Sound waves have amplitude (loudness) and frequency (pitch).
• Sound localization occurs because sounds reach the nearest ear first and are louder in that ear.

Factors Influencing Perception

• Attention (selective, divided, cocktail party effect)
• Inattentional blindness (e.g., change blindness) limits what is perceived.
• Expectations and motivation bias our perception.

Depth Perception

• Depth perception allows us to judge distance and see the world in three dimensions. The visual cliff study illustrates depth perception in infants.

Monocular Depth Cues

• Monocular cues use one eye to perceive distance, including linear perspective, relative size, relative height, light/shadow, interposition, and texture gradients

Binocular Depth Cues

• Binocular cues use both eyes to perceive distance, such as convergence and retinal disparity.

Perceptual Constancies

• Perceptual constancies allow us to perceive objects as stable despite changing retinal images (color, size, shape).

Perceptual Expectations/Set

• Past experiences/expectations shape perceptual interpretation.

Top-Down vs. Bottom-Up Processing

• Top-down processing is conceptually driven. It starts with expectations and prior knowledge.
• Bottom-up processing is data-driven. It starts with raw sensory input.

Additional notes

• Parallel Processing: Stimuli are processed simultaneously.
• Perceptual Adaptation: Adjustments to changed sensory input.

Test your understanding of sensation and perception concepts, including the processes involved in detecting and interpreting sensory information. Explore topics such as thresholds, psychophysics, and the somesthetic senses, gaining insights into how humans perceive the world around them.