Antonyms for the word "more apperceptive" can include less perceptive, less observant, less aware, less insightful, less astute, less discerning, less sensitive, and less cognizant. These antonyms imply a lack of keenness or sharpness in one's ability to perceive, understand, or interpret stimuli. They describe individuals who may struggle to differentiate between multiple sources of stimuli, make connections between concepts, or comprehend subtleties in messages. In contrast, "more apperceptive" implies a heightened sense of awareness and a greater ability to process and synthesize information. Synonyms for this word can include perceptive, insightful, observant, astute, discerning, sensitive, and cognizant.