In Late Adulthood, the Brain Shrinks and Total Brain Mass

question 113

Multiple Choice

In late adulthood, the brain shrinks and total brain mass declines, beginning at age 30 and accelerating at age 60, so that by age 80, most people have lost __________ of their peak brain mass.

• A)5-10%
• B)15-25%
• C)25-45%
• D)45-60%

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Definitions:

Telepathy

The supposed communication of thoughts or ideas by means other than the known senses.

Difference Thresholds

The minimum difference in stimulation that a person can detect 50 percent of the time, also known as the just noticeable difference (JND).

Absolute Thresholds

The minimum stimulus intensity required to be perceptible to the senses.

Sensory Adaptation

The process by which sensory receptors become less sensitive to constant stimuli over time, reducing our awareness of them.