By About 12 Months, Most Infants __________

question 18

Multiple Choice

By about 12 months, most infants __________

• A) begin to use intonation in their language.
• B) build a vocabulary of one-word phrases.
• C) begin to distinguish, in their language, between themselves and others.
• D) begin to form two- and three-word sentences.

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Definitions:

Yerkes-Dodson Law

The psychological principle stating that performance is best under conditions of moderate arousal rather than either low or high arousal.

Moderate Arousal

Refers to an optimal level of alertness or physical and mental activation at which performance on a task is best.

Cholecystokinin (CCK)

a hormone that is released by the intestines in response to eating certain foods and stimulates the digestion of fat and protein.

Motivation

The process that initiates, guides, and maintains goal-oriented behaviors, driving individuals to pursue and achieve their objectives.