Abstract: PURPOSE: Previous research has demonstrated that biological motion (BM) cues can induce a reflexive attentional orienting effect, a phenomenon referred as to social attention. However, it remains unknown whether BM cues can further affect higher-order cognitive processes, such as visual working memory (WM).
METHODS: The present study aimed to probe this issue by adopting a modified central pre-cueing paradigm combined with a traditional WM change detection task. Specifically, the point-light BM stimuli were adopted as a non-predictive central cue. Participants were required to perform a change detection task immediately after viewing the central cue. We also adopted feet motion sequences as central cues to further investigate whether WM performance would be affected by local BM cues without global configuration.
RESULTS: Results revealed a significant improvement in WM performance for the items appearing at the location cued by the walking direction of BM. The observed effect disappeared when the BM cues were shown inverted, or when the critical biological characteristics of the cues were removed. Crucially, this effect could be extended to upright feet motion cues without global configuration, reflecting the key role of local BM signals in modulating WM. More importantly, such BM-induced modulation effect was not observed with inanimate motion cues, although these cues can also elicit attentional effects.
CONCLUSIONS: The current study suggests that the attentional effect induced by life motion signals can penetrate to higher-order cognitive processes, and provide compelling evidence for the existence of “life motion detector” in the human brain from a high-level cognitive function perspective.

Key words: biological motion, working memory, social attention, life motion detector