Guido Hesselmann

Psychologische Hochschule Berlin · Department of Psychology

To what degree human cognition is influenced by subliminal stimuli is a controversial empirical question. One striking example was reported by Linser and Goschke (2007): participants overestimated how much control they had over objectively uncontrollable stimuli when masked congruent primes were presented immediately before the action. Critically,...

Affective states and traits have been associated with different measures of perceptual stability during binocular rivalry. Diverging approaches to measuring perceptual stability as well as to examination of the role of affective variables have contributed to an inconclusive pattern of findings. Here, we studied the influence of affective traits, su...

Understanding how the brain incorporates sensory and motor information will enable better theory building on human perception and behavior. In this study, we aimed to estimate the influence of predictive mechanisms on the magnitude and variability of sensory attenuation in an online sample. After the presentation of a visual cue stimulus, participa...

The Triple-Code Model stipulates that numerical information from different formats and modalities converges on a common magnitude representation in the Intraparietal Sulcus (IPS). To what extent the representations of all numerosity forms overlap remains unsolved. It has been postulated that the representation of symbolic numerosities (for example,...

The Spatial Numerical Association of Response Codes (SNARC) effect refers to the observation that relatively small (e.g., 1) and large numbers (e.g., 9) elicit faster left-sided and right-sided manual responses, respectively. In a variation known as the attentional SNARC effect, merely looking at numbers caused a left- or rightward shift in covert...

One notion emerging from studies on unconscious visual processing is that different “blinding techniques” seem to suppress the conscious perception of stimuli at different levels of the neurocognitive architecture. However, even when only the results from a single suppression method are compared, the picture of the scope and limits of unconscious v...

Virtual reality (VR) has established itself as a useful tool in the study of human perception in the laboratory. A recent study introduced a new approach to examine visual sensory attenuation (SA) effects in VR. Hand movements triggered the appearance of Gabor stimuli, which were either presented behind the participant's hand - not rendered in VR (...

Affective states and traits have been associated with different measures of perceptual stability during binocular rivalry. Diverging approaches to measuring perceptual stability as well as to examination of the role of affective variables (baseline affective state vs. mood induction; clinical vs. sub-clinical expressions of affective traits) have c...

The debate about the scope and limits of unconscious visual processing under continuous flash suppression (CFS) has created a heterogeneous set of divergent findings that are yet to be reconciled. Attention has been suggested as an important factor in modulating the processing of suppressed visual information under CFS. Specifically, Eo et al. (201...

Studies on unconscious mental processes typically require that participants are unaware of some information (e.g., a visual stimulus). An important methodological question in this field of research is how to deal with data from participants who become aware of the critical stimulus according to some measure of awareness. While it has previously bee...

The notion of cognitive penetrability, i.e., whether perceptual contents can in principle be influenced by non-perceptual factors, has sparked a significant debate over methodological concerns and the correct interpretation of existing findings. In this study, we combined predictive processing models of visual perception and affective states to inv...

Self-generated auditory input is perceived less loudly than the same sounds generated externally. The existence of this phenomenon, called Sensory Attenuation (SA), has been studied for decades and is often explained by motor-based forward models. Recent developments in the research of SA, however, challenge these models. We review the current stat...

Savage et al. argue for musicality as having evolved for the overarching purpose of social bonding. By way of contrast, we highlight contemporary predictive processing models of human cognitive functioning in which the production and enjoyment of music follows directly from the principle of prediction error minimization.

Previous research suggests that selective spatial attention is a determining factor for unconscious processing under continuous flash suppression (CFS), and specifically, that inattention toward stimulus location facilitates its unconscious processing by reducing the depth of CFS (Eo et al., 2016). The aim of our study was to further examine this m...

Current predictive processing accounts consider negative affect to result from elevated rates of prediction error, thereby motivating changes in the degree with which prior expectancies and sensory evidence influence our perceptions. Trait anxiety is associated with the amount of negative affect a person is experiencing and has been linked to aberr...

Access to the digital “all-knowing cloud” has become an integral part of our daily lives. It has been suggested that the increasing offloading of information and information processing services to the cloud will alter human cognition and metacognition in the short and long term. A much-cited study published in Science in 2011 provided first behavio...

Abstract Numbers can be presented in different notations and sensory modalities. It is currently debated to what extent these formats overlap onto a single representation. We asked whether such an overlap exists between symbolic numbers represented in two sensory modalities: Arabic digits and Braille numbers. A unique group of sighted Braille reade...

In our review, we show that Sklar, Goldstein, and Hassin’s (SGH) critical discussion of Shanks (2017) is lacking strong arguments that would allow to conclude that “regression to the mean does not explain away non-conscious processing” (title). In its current form, the manuscript by SGA (https://psyarxiv.com/evcgy/) is not a useful contribution to...

Our ability to perceive two events in close temporal succession is severely limited, a phenomenon known as the attentional blink. While the blink has served as a popular tool to prevent conscious perception, there is less research on its causes, and in particular on the role of conscious perception of the first event in triggering it. In three expe...

The attentional blink refers to the deficit in reporting the second of 2 targets (T2), when it appears within 600ms after the first (T1). We examined which aspect of T1 processing triggers the AB. In three experiments, we disentangled the roles of spatial attention, conscious perception and working memory (WM) in causing the blink. We show that whi...

Quantities can be represented by different formats (e.g. symbolic or non-symbolic) and conveyed via different modalities (e.g. tactile or visual). Despite different priming curves: V-shape and step-shape for place and summation coded representation, respectively, the occurrence of priming effect supports the notion of different format overlap on th...

In 2012, a study by Sklar et al. reported that participants could solve invisible subtractions. This notion of unconscious arithmetic has been influential because it challenges current theories of consciousness. In 2016, Karpinski et al. published a direct replication reporting evidence for unconscious addition rather than subtraction. About a year...

Understanding the organising principles and functional properties of the primate brain's numerous visually responsive cortical regions is one of the major goals in cognitive neuroscience. Functional magnetic resonance imaging (fMRI) studies have revealed that neural responses in higher-order visual cortex are shaped by object categories, task conte...

The study of nonconscious priming is rooted in a long research tradition in experimental psychology and plays an important role for a range of topics, including visual recognition, emotion, decision making, and memory. Prime stimuli can be transiently suppressed from awareness by using a variety of psychophysical paradigms. The aim is to understand...

Previous studies have proposed that potentially action-relevant visual features of masked images are processed along the dorsal visual pathway, and can thus prime responses to images of man-made manipulable objects (tools). According to the "category priming by elongation" hypothesis, (invisible) stimulus elongation is the basis for how the dorsal...

Recent studies using continuous flash suppression suggest that invisible stimuli are processed as integrated, semantic entities. We challenge the viability of this account, given recent findings on the neural basis of interocular suppression and replication failures of high-profile CFS studies. We conclude that CFS reveals stimulus fractionation in...

Breaking Continuous Flash Suppression (bCFS) has been adopted as an appealing means to study human visual awareness, but the literature is beclouded by inconsistent and contradictory results. Although previous reviews have focused chiefly on design pitfalls and instances of false reasoning, we show in this study that the choice of analysis pathway...

In this perspective article, we first outline the large diversity of methods, measures, statistical analyses, and concepts in the field of the experimental study of unconscious processing. We then suggest that this diversity implies that comparisons between different studies on unconscious processing are fairly limited, especially when stimulus awa...

In bistable vision, subjective perception wavers between two interpretations of a constant ambiguous stimulus. This dissociation between conscious perception and sensory stimulation has motivated various empirical studies on the neural correlates of bistable perception, but the neurocomputational mechanism behind endogenous perceptual transitions h...

Validation against established models of bistable perception. In this supplement, we provide a validation of our modelling approach against established models of bistable perception based on adaptation and inhibition [1], noise [2] and an intermediate model [3]. (PDF)

Mathematical appendix. The appendix contains a detailed mathematical description of our modelling procedures. (PDF)

Example of a full rotation of the specific Lissajous figure used in this experiment. (WMV)

A recent study claimed to have obtained evidence that participants can solve invisible multistep arithmetic equations (Sklar et al., 2012). The authors used a priming paradigm in which reaction times to targets congruent with the equation’s solution were responded to faster compared with incongruent ones. We critically reanalyzed the data set of Sk...

Lissajous figures represent ambiguous structure-from-motion stimuli rotating in depth and have proven to be a versatile tool to explore the cognitive and neural mechanisms underlying bistable perception. They are generated by the intersection of two sinusoids with perpendicular axes and increasing phase-shift whose frequency determines the speed of...

As a functional organization principle in cortical visual information processing, the influential 'two visual systems' hypothesis proposes a division of labor between a dorsal "vision-for-action" and a ventral "vision-for-perception" stream. A core assumption of this model is that the two visual streams are differentially involved in visual awarene...

Continuous flash suppression (CFS) is an interocular suppression technique that uses high-contrast masks flashed to one eye to prevent conscious perception of images shown to the other eye. It has become widely used due to its strength and prolonged duration of suppression and its nearly deterministic control of suppression onset and offset. Recent...

Working memory (WM) is closely linked to conscious awareness: In most conceptions of WM, the inputs to WM need to be conscious. The findings of some recent studies, however, have been taken to suggest that WM can indeed operate on non-conscious inputs. Here, we argue that these findings can easily be accommodated by conventional conceptions of non-...

Hassin recently proposed the “Yes It Can” (YIC) principle to describe the division of labor between conscious and unconscious processes in human cognition. According to this principle, unconscious processes can carry out every fundamental high-level cognitive function that conscious processes can perform. In our commentary, we argue that the author...

The scope and limits of unconscious processing are a controversial topic of research in experimental psychology. Particularly within the visual domain, a wide range of paradigms have been used to experimentally manipulate perceptual awareness. A recent study reported unconscious numerical processing during continuous flash suppression (CFS), which...

With the introduction of continuous flash suppression (CFS) as a method to render stimuli invisible and study unconscious visual processing, a novel hypothesis has gained popularity. It states that processes typically ascribed to the dorsal visual stream can escape CFS and remain functional, while ventral stream processes are suppressed when stimul...

Studies show that manipulating certain training features in perceptual learning determines the specificity of the improvement. The improvement in abnormal visual processing following training and its generalization to visual acuity, as measured on static clinical charts, can be explained by improved sensitivity or processing speed. Crowding, the in...

Recent behavioral and neuroimaging studies using continuous flash suppression (CFS) have suggested that action-related processing in the dorsal visual stream might be independent of perceptual awareness, in line with the “vision-for-perception” versus “vision-for-action” distinction of the influential dual-stream theory. It remains controversial if...

When dissimilar stimuli are presented to the two eyes, only one stimulus dominates at a time while the other stimulus is invisible due to interocular suppression. When both stimuli are equally potent in competing for awareness, perception alternates spontaneously between the two stimuli, a phenomenon called binocular rivalry. However, when one stim...

During bistable vision perception spontaneously "switches" between two mutually exclusive percepts despite constant sensory input. The endogenous nature of these perceptual transitions has motivated extensive research aimed at the underlying mechanisms, since spontaneous perceptual transitions of bistable stimuli should in principle allow for a dis...

During bistable vision, perception oscillates between two mutually exclusive percepts despite constant sensory input. Greater BOLD responses in frontoparietal cortex have been shown to be associated with endogenous perceptual transitions compared with "replay" transitions designed to closely match bistability in both perceptual quality and timing....

A central implication of the two-visual-systems hypothesis (TVSH) is that the dorsal visuomotor system (vision-for-action) can make use of invisible information, whereas the ventral system (vision-for-perception) cannot (Milner & Goodale, 1995). Therefore, actions such as grasping movements should be influenced by invisible information while consci...

The rules governing the selection of which sensory information reaches consciousness are yet unknown. Of our senses, vision is often considered to be the dominant sense, and the effects of bodily senses, such as proprioception, on visual consciousness are frequently overlooked. Here, we demonstrate that the position of the body influences visual co...

In recent years, substantial progress has been made in the scientific study of perceptual awareness, or synonymously, the contents of consciousness. By many standards, the field of consciousness research is in a phase of unprecedented productivity and progress, with high-impact publications, popular science books, specialized journals, dedicated ac...

Both our environment and our behavior contain many spatiotemporal regularities. Preferential and differential tuning of neural populations to these regularities can be demonstrated by assessing rate dependence of neural responses evoked during continuous periodic stimulation. Here, we used functional magnetic resonance imaging to measure regional v...

The idea of a division between a dorsal and a ventral visual stream is one of the most basic principles of visual processing in the brain ([Milner and Goodale, 1995][1]). The ventral stream originates in primary visual cortex and extends along the ventral surface into the temporal cortex; the dorsal

Clinical diagnosis of disorders of consciousness (DOC) caused by brain injury poses great challenges since patients are often behaviorally unresponsive. A promising new approach towards objective DOC diagnosis may be offered by the analysis of ultra-slow (<0.1 Hz) spontaneous brain activity fluctuations measured with functional magnetic resonance i...

Voxel-by-voxel differences in Spontaneous BOLD correlations between intact- and impaired-awareness groups. Statistical maps of two-sample t-tests (see Methods) comparing BOLD signal correlations in the two subject groups (intact, n = 12; impaired, n = 7) separately for each voxel. Maps are projected on inflated cortical surfaces as seen from latera...

Correlations between Spontaneous BOLD fluctuations in right post-central gyrus and all other cortical regions. Group correlation maps between a “seed” region in the post-central gyrus (postCG) and all other cortical voxels. (A) Correlations of spontaneous activity in the intact awareness group (n = 12) projected on inflated hemispheres as seen from...

Clinical, electrophysiological and structural imaging data of patients. Abbreviations: LIS, locked-in syndrome; VS, vegetative state; MCS, minimally conscious state. (DOCX)

Correlations between spontaneous BOLD fluctuations in right pre-central gyrus and all other cortical regions. Group correlation maps between a “seed” region in the pre-central gyrus (preCG) and all other cortical voxels. (a) Correlations of spontaneous activity in the intact awareness group (n = 12) projected on inflated hemispheres as seen from a...

Single subject inter-hemispheric correlation maps (seed: right PreCG) ordered according to the ICD values. Correlation maps with a “seed” time-course in the right pre-central gyrus (pre-CG) are shown in flat, left hemisphere (“mirror site”) cortical format for each subject separately. (a) Location of seed (red ellipse) and location of the “mirror s...

Inter-operator correlation of ICD measure. ICD values as computed on a subsample of 11 subjects by two independent operators drawing the ROIs. Abbreviations: CCC, concordance correlation coefficient; r, Pearson correlation. (TIF)

Inter-hemispheric Correlation Index (ICD) in individual subjects in all three groups. Subjects are separated on the x-axis depending on their group (controls1: non-aged matched group; controls2: aged-matched group, and patients). Abbreviations: (*) refers to the VS patient who regained consciousness shortly after scan (VS2 in the supplementary tabl...

Inter-operator variability analysis. (DOC)

Comparison of the ICD to an aged-matched control group. (DOCX)

Correlations between spontaneous BOLD fluctuations in right intra-parietal sulcus and all other cortical regions. Group correlation maps between a “seed” region in the intra-parietal sulcus (IPS) and all other cortical voxels. (A) Correlations of spontaneous activity in the intact awareness group (n = 12) projected on inflated hemispheres as seen f...

ICD values and Crawford and Howell test results for the age-matched sample. Abbreviations: LIS, locked-in syndrome; VS, vegetative state; MCS, minimally conscious state. (DOCX)

Inter-operator variability data. Abbreviations: IPS, intra-parietal sulcus; preCG, pre-central gyrus; postCG, post-central gyrus. (DOCX)

When two concurrent sensorimotor tasks have to be performed at a short time interval, the second response is generally delayed at a central decision stage. However, in patients who have undergone full or partial transection of forebrain fibers connecting the two hemispheres (split-brain), independent structures subserving all processing stages shou...

The paradigm of distractor-induced blindness has previously been used to track the transition from unconscious to conscious visual processing. In a variation of this paradigm used in this study, participants (n = 13) had to detect an orientation change of tilted bars (target) embedded in a dynamic random pattern; the onset of the target was signale...

The study of conscious visual perception invariably necessitates some means of report. Report can be either subjective, i.e., an introspective evaluation of conscious experience, or objective, i.e., a forced-choice discrimination regarding different stimulus states. However, the link between report type and fMRI-BOLD signals has remained unknown. H...

The conscious perception of simple visual stimuli can be modulated by the presence of distractors. In the motion blindness paradigm, the detection of coherent motion is impaired when task-irrelevant motion distractors are presented prior to the target. Aim of this study was to examine the feature specificity of the distractor effect. For this reaso...

A central topic of controversy in the search for cortical mechanisms underlying perceptual awareness concerns the fundamental specialization of the visual system into a dorsal "vision-for-action/Where" stream and a ventral "vision-for-perception/What" stream. Specifically, it has been debated whether suppression of visual perception leads to differ...

Human performance exhibits strong multi-tasking limitations in simple response time tasks. In the psychological refractory period (PRP) paradigm, where two tasks have to be performed in brief succession, central processing of the second task is delayed when the two tasks are performed at short time intervals. Here, we aimed to probe the cortical ne...

Ongoing brain activity has been observed since the earliest neurophysiological recordings and is found over a wide range of temporal and spatial scales. It is characterized by remarkably large spontaneous modulations. Here, we review evidence for the functional role of these ongoing activity fluctuations and argue that they constitute an essential...