When Two Patterns of Dots Moving Horizontally in Opposite Directions

question 9

Multiple Choice

When two patterns of dots moving horizontally in opposite directions are superimposed, they may produce motion transparency. Which characteristics of the patterns produce transparency?

• A) The dots in each pattern must move at the same speeds
• B) The patterns must be of the same size
• C) The dots in each pattern must have the same lifetime
• D) The dots on one pattern must be vertically displaced from the dots in the other

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Definitions:

Dysphonia

Difficulty in speaking due to a problem with voice production.

Diaphragm

A large, dome-shaped muscle located at the base of the lungs, playing a crucial role in breathing.

Glottis

The part of the larynx consisting of the vocal cords and the slit-like opening between them.

Ventricular Fold

The ventricular fold, also known as the false vocal cord, is a structure in the larynx that plays a role in the protection of the vocal cords and in respiratory functions.