Normal visual sensation in the absence of complete visual perception is best illustrated by which of the following phenomena?

• A. Visual agnosia
• B. Blindsight
• C. Color constancy
• D. Change blindness

Answer: (B)

Verified step by step guidance

1. Understand the key terms in the problem: 'normal visual sensation' means the eyes and early visual processing are functioning, while 'absence of complete visual perception' means the person is not fully aware of or cannot consciously recognize what they see.
2. Review each option to see which best fits this description: Visual agnosia involves difficulty recognizing objects despite normal vision; color constancy is about perceiving colors consistently under different lighting; change blindness is failing to notice changes in a visual scene.
3. Focus on 'blindsight,' which is a phenomenon where individuals with damage to the primary visual cortex can respond to visual stimuli without conscious visual perception, meaning they have normal sensation but lack full perception.
4. Recognize that blindsight perfectly illustrates the condition described: normal visual sensation without complete visual perception.
5. Conclude that the phenomenon best illustrating the problem statement is 'blindsight' because it demonstrates visual processing without conscious awareness.