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Strijkers K, Bertrand D, Grainger J. Seeing the same words differently: the time course of automaticity and top-down intention in reading. J Cogn Neurosci 2015; 27:1542-51. [PMID: 25761003 DOI: 10.1162/jocn_a_00797] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
We investigated how linguistic intention affects the time course of visual word recognition by comparing the brain's electrophysiological response to a word's lexical frequency, a well-established psycholinguistic marker of lexical access, when participants actively retrieve the meaning of the written input (semantic categorization) versus a situation where no language processing is necessary (ink color categorization). In the semantic task, the ERPs elicited by high-frequency words started to diverge from those elicited by low-frequency words as early as 120 msec after stimulus onset. On the other hand, when categorizing the colored font of the very same words in the color task, word frequency did not modulate ERPs until some 100 msec later (220 msec poststimulus onset) and did so for a shorter period and with a smaller scalp distribution. The results demonstrate that, although written words indeed elicit automatic recognition processes in the brain, the speed and quality of lexical processing critically depends on the top-down intention to engage in a linguistic task.
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Affiliation(s)
- Kristof Strijkers
- CNRS, Aix-en-Provence, France.,Université d'Aix-Marseille, Marseille, France
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52
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Kiefer M, Sim EJ, Wentura D. Boundary conditions for the influence of unfamiliar non-target primes in unconscious evaluative priming: The moderating role of attentional task sets. Conscious Cogn 2015; 35:342-56. [PMID: 25680827 DOI: 10.1016/j.concog.2015.01.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 01/09/2015] [Accepted: 01/19/2015] [Indexed: 11/16/2022]
Abstract
Evaluative priming by masked emotional stimuli that are not consciously perceived has been taken as evidence that affective stimulus evaluation can also occur unconsciously. However, as masked priming effects were small and frequently observed only for familiar primes that there also presented as visible targets in an evaluative decision task, priming was thought to reflect primarily response activation based on acquired S-R associations and not evaluative semantic stimulus analysis. The present study therefore assessed across three experiments boundary conditions for the emergence of masked evaluative priming effects with unfamiliar primes in an evaluative decision task and investigated the role of the frequency of target repetition on priming with pictorial and verbal stimuli. While familiar primes elicited robust priming effects in all conditions, priming effects by unfamiliar primes were reliably obtained for low repetition (pictures) or unrepeated targets (words), but not for targets repeated at a high frequency. This suggests that unfamiliar masked stimuli only elicit evaluative priming effects when the task set associated with the visible target involves evaluative semantic analysis and is not based on S-R triggered responding as for high repetition targets. The present results therefore converge with the growing body of evidence demonstrating attentional control influences on unconscious processing.
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Affiliation(s)
- Markus Kiefer
- University of Ulm, Department of Psychiatry, Germany.
| | - Eun-Jim Sim
- University of Ulm, Department of Psychiatry, Germany
| | - Dirk Wentura
- Saarland University, Department of Psychology, Germany
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53
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Ulrich M, Adams SC, Kiefer M. Flexible establishment of functional brain networks supports attentional modulation of unconscious cognition. Hum Brain Mapp 2014; 35:5500-16. [PMID: 24954512 DOI: 10.1002/hbm.22566] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 06/04/2014] [Accepted: 06/04/2014] [Indexed: 11/06/2022] Open
Abstract
In classical theories of attention, unconscious automatic processes are thought to be independent of higher-level attentional influences. Here, we propose that unconscious processing depends on attentional enhancement of task-congruent processing pathways implemented by a dynamic modulation of the functional communication between brain regions. Using functional magnetic resonance imaging, we tested our model with a subliminally primed lexical decision task preceded by an induction task preparing either a semantic or a perceptual task set. Subliminal semantic priming was significantly greater after semantic compared to perceptual induction in ventral occipito-temporal (vOT) and inferior frontal cortex, brain areas known to be involved in semantic processing. The functional connectivity pattern of vOT varied depending on the induction task and successfully predicted the magnitude of behavioral and neural priming. Together, these findings support the proposal that dynamic establishment of functional networks by task sets is an important mechanism in the attentional control of unconscious processing.
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Affiliation(s)
- Martin Ulrich
- Department of Psychiatry, University of Ulm, 89075, Ulm, Germany
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54
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Ansorge U, Kunde W, Kiefer M. Unconscious vision and executive control: how unconscious processing and conscious action control interact. Conscious Cogn 2014; 27:268-87. [PMID: 24960432 DOI: 10.1016/j.concog.2014.05.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Revised: 04/29/2014] [Accepted: 05/20/2014] [Indexed: 10/25/2022]
Abstract
Research on unconscious or unaware vision has demonstrated that unconscious processing can be flexibly adapted to the current goals of human agents. The present review focuses on one area of research, masked visual priming. This method uses visual stimuli presented in a temporal sequence to lower the visibility of one of these stimuli. In this way, a stimulus can be masked and even rendered invisible. Despite its invisibility, a masked stimulus if used as a prime can influence a variety of executive functions, such as response activation, semantic processing, or attention shifting. There are also limitations on the processing of masked primes. While masked priming research demonstrates the top-down dependent usage of unconscious vision during task-set execution it also highlights that the set-up of a new task-set depends on conscious vision as its input. This basic distinction captures a major qualitative difference between conscious and unconscious vision.
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Affiliation(s)
- Ulrich Ansorge
- Fakultät für Psychologie, Universität Wien, Austria; Institut für Kognitionswissenschaften, Universität Osnabrück, Germany.
| | - Wilfried Kunde
- Abteilung für Psychologie, Julius-Maximilians-Universität Würzburg, Germany
| | - Markus Kiefer
- Klinik für Psychiatrie und Psychotherapie III, Universität Ulm, Germany
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55
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Ferrari V, Mastria S, Bruno N. Crossmodal interactions during affective picture processing. PLoS One 2014; 9:e89858. [PMID: 24587078 PMCID: PMC3937419 DOI: 10.1371/journal.pone.0089858] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 01/24/2014] [Indexed: 12/02/2022] Open
Abstract
"Natural" crossmodal correspondences, such as the spontaneous tendency to associate high pitches with high spatial locations, are often hypothesized to occur preattentively and independently of task instructions (top-down attention). Here, we investigate bottom-up attentional engagement by using emotional scenes that are known to naturally and reflexively engage attentional resources. We presented emotional (pleasant and unpleasant) or neutral pictures either below or above a fixation cross, while participants were required to discriminate between a high or a low pitch tone (experiment 1). Results showed that despite a robust crossmodal attentional capture of task-irrelevant emotional pictures, the general advantage in classifying the tones for congruent over incongruent visual-auditory stimuli was similar for emotional and neutral pictures. On the other hand, when picture position was task-relevant (experiment 2), task-irrelevant tones did not interact with pictures with regard to their combination of pitch and visual vertical spatial position, but instead they were effective in minimizing the interference effect of emotional picture processing on the ongoing task. These results provide constraints on our current understanding of natural crossmodal correspondences.
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Affiliation(s)
- Vera Ferrari
- Department of Neuroscience, University of Parma, Parma, Italy
- * E-mail:
| | - Serena Mastria
- Department of Psychology, University of Bologna, Bologna, Italy
| | - Nicola Bruno
- Department of Neuroscience, University of Parma, Parma, Italy
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56
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Cossy N, Tzovara A, Simonin A, Rossetti AO, De Lucia M. Robust discrimination between EEG responses to categories of environmental sounds in early coma. Front Psychol 2014; 5:155. [PMID: 24611061 PMCID: PMC3933775 DOI: 10.3389/fpsyg.2014.00155] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 02/07/2014] [Indexed: 01/18/2023] Open
Abstract
Humans can recognize categories of environmental sounds, including vocalizations produced by humans and animals and the sounds of man-made objects. Most neuroimaging investigations of environmental sound discrimination have studied subjects while consciously perceiving and often explicitly recognizing the stimuli. Consequently, it remains unclear to what extent auditory object processing occurs independently of task demands and consciousness. Studies in animal models have shown that environmental sound discrimination at a neural level persists even in anesthetized preparations, whereas data from anesthetized humans has thus far provided null results. Here, we studied comatose patients as a model of environmental sound discrimination capacities during unconsciousness. We included 19 comatose patients treated with therapeutic hypothermia (TH) during the first 2 days of coma, while recording nineteen-channel electroencephalography (EEG). At the level of each individual patient, we applied a decoding algorithm to quantify the differential EEG responses to human vs. animal vocalizations as well as to sounds of living vocalizations vs. man-made objects. Discrimination between vocalization types was accurate in 11 patients and discrimination between sounds from living and man-made sources in 10 patients. At the group level, the results were significant only for the comparison between vocalization types. These results lay the groundwork for disentangling truly preferential activations in response to auditory categories, and the contribution of awareness to auditory category discrimination.
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Affiliation(s)
- Natacha Cossy
- Electroencephalography Brain Mapping Core, Center for Biomedical Imaging (CIBM), University Hospital Center, University of Lausanne Lausanne, Switzerland ; Department of Radiology, University Hospital Center, University of Lausanne Lausanne, Switzerland
| | - Athina Tzovara
- Electroencephalography Brain Mapping Core, Center for Biomedical Imaging (CIBM), University Hospital Center, University of Lausanne Lausanne, Switzerland ; Department of Radiology, University Hospital Center, University of Lausanne Lausanne, Switzerland
| | - Alexandre Simonin
- Department of Clinical Neurosciences, University Hospital Center, University of Lausanne Lausanne, Switzerland
| | - Andrea O Rossetti
- Department of Clinical Neurosciences, University Hospital Center, University of Lausanne Lausanne, Switzerland
| | - Marzia De Lucia
- Electroencephalography Brain Mapping Core, Center for Biomedical Imaging (CIBM), University Hospital Center, University of Lausanne Lausanne, Switzerland ; Department of Radiology, University Hospital Center, University of Lausanne Lausanne, Switzerland
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57
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A new perspective on human reward research: How consciously and unconsciously perceived reward information influences performance. COGNITIVE AFFECTIVE & BEHAVIORAL NEUROSCIENCE 2014; 14:493-508. [DOI: 10.3758/s13415-013-0241-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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58
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Kiefer M, Morschett A, Schönfeldt-Lecuona C, Spitzer M, Kammer T. Altered time course of unconscious response priming in schizophrenia patients. Schizophr Res 2013; 150:590-1. [PMID: 24035563 DOI: 10.1016/j.schres.2013.08.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 07/23/2013] [Accepted: 08/10/2013] [Indexed: 11/16/2022]
Affiliation(s)
- Markus Kiefer
- University of Ulm, Department of Psychiatry, Germany.
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59
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Electrophysiological evidence for greater attention to threat when cognitive control resources are depleted. COGNITIVE AFFECTIVE & BEHAVIORAL NEUROSCIENCE 2013; 14:827-35. [DOI: 10.3758/s13415-013-0212-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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60
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Trumpp NM, Traub F, Pulvermüller F, Kiefer M. Unconscious automatic brain activation of acoustic and action-related conceptual features during masked repetition priming. J Cogn Neurosci 2013; 26:352-64. [PMID: 24001008 DOI: 10.1162/jocn_a_00473] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Classical theories of semantic memory assume that concepts are represented in a unitary amodal memory system. In challenging this classical view, pure or hybrid modality-specific theories propose that conceptual representations are grounded in the sensory-motor brain areas, which typically process sensory and action-related information. Although neuroimaging studies provided evidence for a functional-anatomical link between conceptual processing of sensory or action-related features and the sensory-motor brain systems, it has been argued that aspects of such sensory-motor activation may not directly reflect conceptual processing but rather strategic imagery or postconceptual elaboration. In the present ERP study, we investigated masked effects of acoustic and action-related conceptual features to probe unconscious automatic conceptual processing in isolation. Subliminal feature-specific ERP effects at frontocentral electrodes were observed, which differed with regard to polarity, topography, and underlying brain electrical sources in congruency with earlier findings under conscious viewing conditions. These findings suggest that conceptual acoustic and action representations can also be unconsciously accessed, thereby excluding any postconceptual strategic processes. This study therefore further substantiates a grounding of conceptual and semantic processing in action and perception.
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61
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Everaert T, Spruyt A, Rossi V, Pourtois G, De Houwer J. Feature-specific attention allocation overrules the orienting response to emotional stimuli. Soc Cogn Affect Neurosci 2013; 9:1351-9. [PMID: 23903491 DOI: 10.1093/scan/nst121] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Emotional stimuli are generally thought to be processed in an unconditional fashion. Recent behavioral studies suggest, however, that emotional stimulus processing is critically dependent on attention toward emotional stimulus features. We set out to test this hypothesis using EEG measurements and a modified oddball paradigm. Unexpected emotional stimuli evoked amplitude variations of the P3a (an ERP marker of attention orienting) when attention was directed to emotional stimulus properties but not when non-emotional stimulus properties were attended to. We conclude that emotional stimulus processing is not unconditional, but dependent on top-down attentional control.
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Affiliation(s)
- Tom Everaert
- Department of Psychology, Ghent University, Henri Dunantlaan 2, B-9000 Ghent, Belgium
| | - Adriaan Spruyt
- Department of Psychology, Ghent University, Henri Dunantlaan 2, B-9000 Ghent, Belgium
| | - Valentina Rossi
- Department of Psychology, Ghent University, Henri Dunantlaan 2, B-9000 Ghent, Belgium
| | - Gilles Pourtois
- Department of Psychology, Ghent University, Henri Dunantlaan 2, B-9000 Ghent, Belgium
| | - Jan De Houwer
- Department of Psychology, Ghent University, Henri Dunantlaan 2, B-9000 Ghent, Belgium
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62
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Trumpp NM, Traub F, Kiefer M. Masked priming of conceptual features reveals differential brain activation during unconscious access to conceptual action and sound information. PLoS One 2013; 8:e65910. [PMID: 23741518 PMCID: PMC3669239 DOI: 10.1371/journal.pone.0065910] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Accepted: 05/04/2013] [Indexed: 01/08/2023] Open
Abstract
Previous neuroimaging studies suggested an involvement of sensory-motor brain systems during conceptual processing in support of grounded cognition theories of conceptual memory. However, in these studies with visible stimuli, contributions of strategic imagery or semantic elaboration processes to observed sensory-motor activity cannot be entirely excluded. In the present study, we therefore investigated the electrophysiological correlates of unconscious feature-specific priming of action- and sound-related concepts within a novel feature-priming paradigm to specifically probe automatic processing of conceptual features without the contribution of possibly confounding factors such as orthographic similarity or response congruency. Participants were presented with a masked subliminal prime word and a subsequent visible target word. In the feature-priming conditions primes as well as targets belonged to the same conceptual feature dimension (action or sound, e.g., typewriter or radio) whereas in the two non-priming conditions, either the primes or the targets consisted of matched control words with low feature relevance (e.g., butterfly or candle). Event-related potential analyses revealed unconscious feature-specific priming effects at fronto-central electrodes within 100 to 180 ms after target stimulus onset that differed with regard to topography and underlying neural generators. In congruency with previous findings under visible stimulation conditions, these differential subliminal ERP feature-priming effects demonstrate an unconscious automatic access to action versus sound features of concepts. The present results therefore support grounded cognition theory suggesting that activity in sensory and motor areas during conceptual processing can also occur unconsciously and is not mandatorily accompanied by a vivid conscious experience of the conceptual content such as in imagery.
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Affiliation(s)
| | - Felix Traub
- Department of Psychiatry, University of Ulm, Ulm, Germany
| | - Markus Kiefer
- Department of Psychiatry, University of Ulm, Ulm, Germany
- * E-mail:
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63
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De Pisapia N. Unconscious information processing in executive control. Front Hum Neurosci 2013; 7:21. [PMID: 23386822 PMCID: PMC3560345 DOI: 10.3389/fnhum.2013.00021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Accepted: 01/16/2013] [Indexed: 11/13/2022] Open
Affiliation(s)
- Nicola De Pisapia
- Department of Cognitive Science and Education, University of Trento Rovereto, Italy
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64
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Breitmeyer BG, Jahshan C, Wynn JK, Green MF. Response to Vakalopoulos' letter to the editor Re: Nonconscious and conscious color priming in schizophrenia. J Psychiatr Res 2013; 47:138-9. [PMID: 23157801 DOI: 10.1016/j.jpsychires.2012.09.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Accepted: 09/26/2012] [Indexed: 11/24/2022]
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65
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Kiang M, Patriciu I, Roy C, Christensen BK, Zipursky RB. Test-retest reliability and stability of N400 effects in a word-pair semantic priming paradigm. Clin Neurophysiol 2012; 124:667-74. [PMID: 23122708 DOI: 10.1016/j.clinph.2012.09.029] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Revised: 08/31/2012] [Accepted: 09/09/2012] [Indexed: 10/27/2022]
Abstract
OBJECTIVE Elicited by any meaningful stimulus, the N400 event-related potential (ERP) component is reduced when the stimulus is related to a preceding one. This N400 semantic priming effect has been used to probe abnormal semantic relationship processing in clinical disorders, and suggested as a possible biomarker for treatment studies. Validating N400 semantic priming effects as a clinical biomarker requires characterizing their test-retest reliability. METHODS We assessed test-retest reliability of N400 semantic priming in 16 healthy adults who viewed the same related and unrelated prime-target word pairs in two sessions one week apart. RESULTS As expected, N400 amplitudes were smaller for related versus unrelated targets across sessions. N400 priming effects (amplitude differences between unrelated and related targets) were highly correlated across sessions (r=0.85, P<0.0001), but smaller in the second session due to larger N400s to related targets. CONCLUSIONS N400 priming effects have high reliability over a one-week interval. They may decrease with repeat testing, possibly because of motivational changes. SIGNIFICANCE Use of N400 priming effects in treatment studies should account for possible magnitude decreases with repeat testing. Further research is needed to delineate N400 priming effects' test-retest reliability and stability in different age and clinical groups, and with different stimulus types.
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Affiliation(s)
- Michael Kiang
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Ontario, Canada.
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66
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Wykowska A, Schubö A. Action intentions modulate allocation of visual attention: electrophysiological evidence. Front Psychol 2012; 3:379. [PMID: 23060841 PMCID: PMC3464057 DOI: 10.3389/fpsyg.2012.00379] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Accepted: 09/13/2012] [Indexed: 12/03/2022] Open
Abstract
In line with the Theory of Event Coding (Hommel et al., 2001), action planning has been shown to affect perceptual processing – an effect that has been attributed to a so-called intentional weighting mechanism (Wykowska et al., 2009; Hommel, 2010). This paper investigates the electrophysiological correlates of action-related modulations of selection mechanisms in visual perception. A paradigm combining a visual search task for size and luminance targets with a movement task (grasping or pointing) was introduced, and the EEG was recorded while participants were performing the tasks. The results showed that the behavioral congruency effects, i.e., better performance in congruent (relative to incongruent) action-perception trials have been reflected by a modulation of the P1 component as well as the N2pc (an ERP marker of spatial attention). These results support the argumentation that action planning modulates already early perceptual processing and attention mechanisms.
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Affiliation(s)
- Agnieszka Wykowska
- General and Experimental Psychology Unit, Department Psychologie, Ludwig-Maximilians-Universität in Munich Munich, Germany
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