DOI: 10.3724/SP.J.1041.2018.00473

Acta Psychologica Sinica (心理学报) 2018/50:5 PP.473-482

The stimulus representation of unconscious information and its temporal characteristics

The current study reports three experiments to test whether and how unconscious activation of distractors with subliminal presentation, especially at stimulus level, affects response to targets in a letter flanker task.
In each experiment, the flanker letters were made unconscious using visually backward masking letters. As classic Flanker tasks, the congruency between target letters and flankers were manipulated to form three conditions-conflicting at stimulus level, conflicting at response level, and non-conflicting. Stimulus conflict referred to trials in which the target and the flankers differed but linked to the same response key, indicating that the competition between the target and flankers occurs at stimulus level. In contrast, response conflict referred to trials where the target and flankers were not only different but also associated with distinct response keys, indicating that the competition between the target and flankers emerges at both the stimulus and response levels. Non-conflict referred to congruent target and flankers trials, used as a baseline condition. Accordingly, the stimulus conflict effect was the difference between stimulus conflict and non-conflict conditions, while the response conflict effect was the difference between response conflict and non-conflict condition. A total of fifty seven participants this study.
Experiment 1A was a baseline experiment with supraliminal flankers, in which the classical effects of stimulus conflict and response conflict were observed. However, when the flankers were made unconscious in Experiment 1B using subliminal flankers, a reversed stimulus conflict effect emerged but the response conflict effect maintained. These results were replicated in Experiment 2 when symbolic stimuli were used to reduce the difficulty in forming a stimulus-response association. Likewise, the effects were observed in Experiment 3 with more stimuli and response types were introduced. Crucially, the effect of stimulus conflict dynamically varied along different time windows, while the effect of response conflict was stable across time windows.
Altogether, the results provided systematically behavioral evidence for the subliminal activation of distractors that affects target performance at both the stimulus and response levels in a flanker task. The data indicated that the unconscious representation of distractors dynamically influences stimulus processing of targets over time but exerts a stable impact on responses. Our findings, especially the unconscious representation at stimulus level can clarify the mechanism and integrate previous contradicting conclusions of unconscious processing.

Key words:unconscious processing,stimulus representation,cognitive conflict,level of representation,flanker task

ReleaseDate:2018-07-02 16:16:00

Beckers, G., & Zeki, S. (1995). The consequences of inactivating areas V1 and V5 on visual motion perception. Brain, 118, 49-60.

Bijleveld, E., Custers, R., van der Stigchel, S., Aarts, H., Pas, P., & Vink, M. (2014). Distinct neural responses to conscious versus unconscious monetary reward cues. Human Brain Mapping, 35(11), 5578-5586.

De Jong, R., Liang, C. C., & Lauber, E. (1994). Conditional and unconditional automaticity:A dual-process model of effects of spatial stimulus-response correspondence. Journal of Experimental Psychology:Human Perception and Performance, 20(4), 731-750.

Eriksen, B. A., & Eriksen, C. W. (1974). Effects of noise letters upon the identification of a target letter in a nonsearch task. Perception & Psychophysics, 16(1), 143-149.

Grainger, J. E., Scharnowski, F., Schmidt, T., & Herzog, M. H. (2013). Two primes priming:Does feature integration occur before response activation? Journal of Vision, 13(8), 19.

Greenwald, A. G., Draine, S. C., & Abrams, R. L. (1996). Three cognitive markers of unconscious semantic activation. Science, 273(5282), 1699-1702.

Kiefer, M. (2002). The N400 is modulated by unconsciously perceived masked words:Further evidence for an automatic spreading activation account of N400 priming effects. Cognitive Brain Research, 13(1), 27-39.

Kiefer, M., & Brendel, D. (2006). Attentional modulation of unconscious "automatic" processes:Evidence from event-related potentials in a masked priming paradigm. Journal of Cognitive Neuroscience, 18(2), 184-198.

Kiefer, M., & Martens, U. (2010). Attentional sensitization of unconscious cognition:Task sets modulate subsequent masked semantic priming. Journal of Experimental Psychology:General, 139(3), 464-489.

Kiefer, M., & Spitzer, M. (2000). Time course of conscious and unconscious semantic brain activation. NeuroReport, 11(11), 2401-2407.

Kiesel, A., Kunde, W., & Hoffmann, J. (2007). Unconscious priming according to multiple S-R rules. Cognition, 104(1), 89-105.

Klinger, M. R., Burton, P. C., & Pitts, G. S. (2000). Mechanisms of unconscious priming:I. Response competition, not spreading activation. Journal of Experimental Psychology:Learning, Memory, and Cognition, 26(2), 441-455.

Koivisto, M., Mäntylä, T., & Silvanto, J. (2010). The role of early visual cortex (V1/V2) in conscious and unconscious visual perception. NeuroImage, 51(2), 828-834.

Lau, H. C., & Passingham, R. E. (2007). Unconscious activation of the cognitive control system in the human prefrontal cortex. Journal of Neuroscience, 27(21), 5805-5811.

Lin, Z., & Murray, S. O. (2014). Unconscious processing of an abstract concept. Psychological Science, 25(1), 296-298.

Martens, U., Ansorge, U., & Kiefer, M. (2011). Controlling the unconscious:Attentional task sets modulate subliminal semantic and visuomotor processes differentially. Psychological Science, 22(2), 282-291.

Mattler, U. (2005). Flanker effects on motor output and the late-level response activation hypothesis. The Quarterly Journal of Experimental Psychology Section A, 58(4), 577-601.

Naccache, L., Blandin, E., & Dehaene, S. (2002). Unconscious masked priming depends on temporal attention. Psychological Science, 13(5), 416-424.

Nakamura, K., Oga, T., & Fukuyama, H. (2012). Task-sensitivity of unconscious word processing in spatial neglect. Neuropsychologia, 50(7), 1570-1577.

Notebaert, W., Houtman, F., van Opstal, F., Gevers, W., Fias, W., & Verguts, T. (2009). Post-error slowing:An orienting account. Cognition, 111(2), 275-279.

Peters, M. A. K., Kentridge, R. W., Phillips, I., & Block, N. (2017). Does unconscious perception really exist? Continuing the ASSC20 debate. Neuroscience of Consciousness, 3(1), nix015, doi:10.1093/nc/nix015.

Rafal, R., Ward, R., & Danziger, S. (2006). Selection for action and selection for awareness:Evidence from hemispatial neglect. Brain Research, 1080(1), 2-8.

Salti, M., Monto, S., Charles, L., King, J. R., Parkkonen, L., & Dehaene, S. (2015). Distinct cortical codes and temporal dynamics for conscious and unconscious percepts. eLife, 4, e05652.

Schubert, T., Palazova, M., & Hutt, A. (2013). The time course of temporal attention effects on nonconscious prime processing. Attention, Perception, & Psychophysics, 75(8), 1667-1686, doi:10.3758/s13414-013-0515-0.

Tapia, E., & Beck, D. M. (2014). Probing feedforward and feedback contributions to awareness with visual masking and transcranial magnetic stimulation. Frontiers in Psychology, 5, 1173.

Tipples, J. (2002). Eye gaze is not unique:Automatic orienting in response to uninformative arrows. Psychonomic Bulletin & Review, 9(2), 314-318.

van Veen, V., Cohen, J. D., Botvinick, M. M., Stenger, V. A., & Carter, C. S. (2001). Anterior cingulate cortex, conflict monitoring, and levels of processing. NeuroImage, 14(6), 1302-1308.

Verbruggen, F., Notebaert, W., Liefooghe, B., & Vandierendonck, A. (2006). Stimulus-and response-conflict-induced cognitive control in the flanker task. Psychonomic Bulletin & Review, 13(2), 328-333.

Vlassova, A., Donkin, C., & Pearson, J. (2014). Unconscious information changes decision accuracy but not confidence. Proceedings of the National Academy of Sciences of the United States of America, 111(45), 16214-16218.

Wang, L., Zhang, L.-W., Zhang, M.-L., & Chen, A.-T. (2013). The status of the nonresponding hand affect Simon effect in the Go/No-Go task. Journal of Psychological Science, 36(1), 38-43.[王力, 张栎文, 张明亮, 陈安涛. (2013). Go/No-Go范式中非反应手状态对Simon效应性质的影响. 心理科学, 36(1), 38-43.]

Wendt, M., Heldmann, M., Münte, T. F., & Kluwe, R. H. (2007). Disentangling sequential effects of stimulus-and response-related conflict and stimulus-response repetition using brain potentials. Journal of Cognitive Neuroscience, 19(7), 1104-1112.

Zhang, D. X., & Zhou, X. L. (2007). Delta plot analysis and its use in conflict control studies. Advances in Psychological Science, 15(3), 545-551.[张德玄, 周晓林. (2007). Delta图分析方法及其在冲突控制研究中的应用. 心理科学进展, 15(3), 545-551.]