The influence of unitization encoding strategy on directed forgetting effect of associative recognition

Objective To investigate the influence of unitization encoding strategy and the moderating effect of unitization level on directed forgetting effect of associative recognition. Methods Association recognition paradigm combined with directed forgetting paradigm were employed in this study.The 39 participants acquired by simple random sampling were asked to remember or forget compound words or unrelated word pairs which were randomly presented according to cues.In the retrieval stage, they needed to distinguish old or rearranged word pairs regardless of the cues. Results (1) The reversed unitization effect reached significance. The discrimination of compound words (0.43±0.03) was lower than that of unrelated words (0.55±0.03) (F=27.27, P<0.001, ηp2=0.42). For the word pairs (to be remembered, TBR), the discrimination of compound words (0.43±0.03) was lower than that of unrelated words (0.59±0.03) (t=-6.05, P<0.001); for the word pairs (to be forgotten, TBF), the discrimination of compound words (0.43±0.03) was still lower than that of unrelated words (0.50±0.04) (t=-2.30, P=0.025). (2) The directed forgetting effect of associative recognition was significant.However, TBR (0.51±0.03) was more discriminative than TBF (0.46±0.03) (F=4.30, P=0.045, ηp2=0.10). But the difference was mainly reflected in the recognition of unrelated words.TBR (0.59±0.03) was more discriminative than TBF (0.50±0.04) (t=3.19, P=0.003). However, there was no significant difference between TBR (0.43±0.03) and TBF (0.43±0.03) in recognition of compound words. Conclusion The unitization encoding stratege can simultaneously promote hit rate and false alarm rate.The directed forgetting effect can be eliminated when unitization level is high enough. Key words: Associative recognition; Directed forgetting; Unitization encoding; Unitization level; Familiarity