When Light from a Flashlight Is Moved Quickly Back and Forth

question 4

Multiple Choice

When light from a flashlight is moved quickly back and forth on a wall in a darkened room, it can appear to observers that there is a trail of light moving across the wall, even though physically the light is only in one place at any given time. This experience is an effect of memory that occurs because of

• A) a visual delay effect.
• B) echoic memory.
• C) persistence of vision.
• D) top-down processing.

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Definitions:

Arousal

A psychological and physiological state of being awake or reactive to stimuli.

Intracellular Thirst

A form of thirst resulting from the osmotic pressure changes within cells, often caused by high intake of salt or loss of water.

Extracellular Thirst

Thirst caused by reduced volume of the extracellular fluid, which is the fluid outside the cells.

Lateral Hypothalamus

A part of the hypothalamus gland which plays a role in hunger and thirst; sometimes referred to as the hunger center of the brain.