Depth of Processing Re-Examined: Semantic Superiority Persists Despite Increased Lexical Task Demands

The present study investigates whether semantic or lexical judgement tasks yield deeper encoding and higher recall accuracy in working and short-term memory. Using the Levels of Processing theory framework, we compared a semantic categorization question, “Is this an animal?” with a more cognitively effortful lexical question, “Is this a word backwards?” to test whether increased cognitive effort improves recall over mental categorization. A self-selecting sample of 31 Utah State University students completed a within-subjects experiment with an encoding phase followed by a recall phase. Word stimuli were controlled for length, frequency, phonological simplicity, and concreteness. Results showed significantly higher recall accuracy for semantically encoded words (84%, SD = 0.098) compared to the lexically encoded words (67%, SD = 0.14; p-value < 0.001***). Lure word accuracy was moderate to good (79%, SD = 0.085), indicating appropriate discrimination by subjects. Despite requiring more processing time, the lexical task did not show deeper encoding, supporting the hypothesis that semantic, meaning-based encoding is more important than cognitive difficulty when studying memory performance.