The Open Data initiative Altered States Database (ASDB) collects psychometric questionnaire data on the subjective experiences of pharmacologically and non-pharmacologically induced altered states of consciousness. The ASDB is updated annually and can be utilized by both researchers and non-scientists to access information or conduct further analyses. The current update adds data published in the year 2025, sourced from a systematic literature review following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A total of 578 items were screened, resulting in 32 included journal articles, of which nineteen report on the Mystical Experience Questionnaire (MEQ30), eighteen on the 11-Altered States of Consciousness Rating Scale (11-ASC), fourteen on the 5D-ASC, two on the Phenomenology of Consciousness Inventory (PCI), and one on the Hallucinogen Rating Scale (HRS). In total, the ASDB now encompasses data from 36 pharmacological and 18 non‑pharmacological consciousness modifying techniques (CMT) (plus control substances/techniques), incorporating 289 journal articles and 836 single datasets from 29.287 participants across datasets. The ASDB can be accessed on https://asdb.info and data tables can be downloaded from Open Science Framework (OSF; https://osf.io/8mbru).

The range of phenomena that can be induced by psychedelic substances is broad and variable, including effects on perception, cognition, and emotion. The umbrella term "psychedelic phenomenology" is used to refer to a combination of altered experiential features, such as hallucinations or ego dissolution, which together constitute a psychedelic experience. However, there is no consensus on the set of alterations of consciousness that qualifies an altered state to be a "psychedelic state." In this chapter we summarize the most commonly discussed changes in subjective experiences which could be seen as "core features" of psychedelic experiences. While acknowledging the rich history of pioneering phenomenological work of the last century, this chapter focuses on more recent developments in the quantitative work on the assessment of these phenomena. We also address the under-researched phenomenology of distressing effects, often referred to as "challenging experiences" or "bad trips," and point to their importance in understanding the therapeutic potential and risks associated with psychedelic phenomenology. Historically, one can find many links between psychedelic phenomenology and the phenomenology of psychopathology. We stress the importance to refine the assessment and description also of distressing effects, to identify factors that promote acute experiences which are beneficial and limit those which can have potentially harmful long-term effects.

Abstract Background Spatial working memory (WM) relies on posterior parietal cortex (PPC) within a distributed fronto-parietal network, yet whether online anodal transcranial direct current stimulation (tDCS) of PPC modulates tactile WM, and how behavioral effects unfold over time, remains unclear. Objective We tested whether online anodal tDCS over left PPC modulates performance in a tactospatial WM task and whether stimulation effects vary over time and as a function of baseline performance. Methods In a double-blind, sham-controlled, within-subject crossover design, 32 healthy adults completed two counterbalanced sessions (Active, Sham). Each session comprised baseline, stimulation, and post-stimulation phases while participants performed a retro-cued delayed match-to-sample task with vibrotactile patterns delivered to the left index finger. During the stimulation phase, participants received either 2 mA anodal or sham tDCS over left PPC for 15 min, depending on session. Behavioral accuracy was analyzed using a sliding-window approach combined with cluster-based permutation testing. Results Active stimulation induced a significant, gradual improvement in WM accuracy relative to sham, emerging approximately eight minutes after stimulation onset and corresponding to a ∼5% performance increase (Hedges’ g = 0.43). Stimulation effects were baseline-dependent, with individuals showing lower initial WM performance exhibiting larger behavioral gains, whereas high performers showed minimal benefits. Conclusions These findings show that online anodal stimulation of left PPC can modulate tactile WM performance in a time- and baseline-dependent manner. More broadly, the results suggest that behavioral effects of parietal tDCS emerge gradually during ongoing stimulation and depend on initial cognitive state. Highlights Online anodal PPC-tDCS enhances tactile working memory Behavioral gains emerge after ∼8 min of stimulation Active stimulation improves accuracy by ∼5% versus sham Lower baseline performers show larger stimulation benefits Sliding-window analyses capture dynamic online tDCS effects

ABSTRACT Motor planning entails a progressive transformation of neural representations—from abstract motor goals, which represent intended action-outcomes independent of any particular effector (i.e., the body part executing the action), to effector-specific movement plans. Functional MRI (fMRI) studies have shown that parametric variations in parietal activity patterns reflect the encoding of intended force intensities in effector-specific regions, even before detailed movement parameters are specified. However, how these intended force intensities are initially represented in an abstract, effector-independent format and subsequently transformed into effector- and movement-specific plans remains unclear. To address this, human participants performed a delayed grip-force task during fMRI. They first prepared two of four possible force intensities, then received a cue indicating which hand should apply which force, and finally executed both grips simultaneously. Using time-resolved support vector regression (SVR) combined with a searchlight approach, we identified brain regions that parametrically code grip-force intensities across two 6-second delay periods. During the first delay, above-chance decoding was observed in the precuneus (PCu), whereas during the second delay it emerged in effector-specific regions, including the contralateral intraparietal sulcus (pIPS/aIPS), primary somatosensory cortex (S1), dorsal premotor cortex (PMd), and supplementary motor area (SMA). Cross-decoding confirmed effector-independent coding in the PCu, while cross-temporal generalization revealed stable representations in the contralateral IPS and PMd from the second delay through execution. Together, these findings indicate a progressive transformation from abstract representations of intended force intensity in the PCu to effector- and movement-specific plans in the IPS and PMd.

Planning motor-actions involves the neuronal representation of key parameters such as force and timing prior to execution. Functional magnetic resonance imaging (fMRI) studies have shown that activity in premotor and parietal areas covaries with these parameters during motor-preparation. While previous research has demonstrated that parametric codes reflect graded grip-force intensities before and after their transformation into motor-codes, it remains unclear whether these representations are encoded in effector-specific brain-regions. To address this, we conducted an fMRI-study using a delayed grip-force task in which participants prepared one of four force-intensities with either their right or left cued-hand, with the hand to-be-used being switched in 50% of the trials midway through the delay. Using time-resolved multivoxel pattern analysis (MVPA) with a searchlight approach, we identified brain-regions encoding anticipated grip-force intensities of the cued-hand across the two 6-s delay-periods. In addition, cross-decoding analyses tested whether force-intensities were represented in an effector-specific or effector-independent format. We found above-chance decoding in two lateralized networks: the contralateral intraparietal sulcus (r-/l-IPS), as well as the lateral occipitotemporal cortex (r-/l-LOTC) during the first, and the contralateral primary motor cortices (r-/l-M1) during the second delay. These results indicate effector-specific coding of anticipated grip-force intensities, which is revealed by systematic lateralization of decoding-accuracy depending on the hand to-be-used. Cross-decoding corroborated effector-specific representation in these regions. Together, our results show that contralateral IPS and LOTCs encode effector-specific parametric information prior to M1s, likely reflecting a transformation process in which the intended grip-force intensity is selected, maintained, and then converted into detailed movement-plans.

Flicker light stimulation induces an intense transient experience of elementary visual hallucinations, such as colored geometric patterns, that has phenomenal similarities to the visual experience induced by psychedelic drugs or during psychopathology. During fMRI scanning, we found that increased connectivity between ventroanterior thalamic nuclei and higher order visual cortices was associated with the reported intensity of the flicker-induced visual effects. Our results suggest that the role of thalamocortical hyperconnectivity during hallucinatory experiences may relate to a higher order function of the thalamus, such as the regulation of cortical activity. This novel finding results from a highly controlled experimental setup, which can be extended to inform the mechanistic underpinnings of hallucinatory experiences during psychopathology.

In recent years, there has been a renewed interest in the conceptual and empirical study of altered states of consciousness (ASCs), induced pharmacologically or otherwise, driven by their potential clinical applications. To draw attention to the rich history of research in this domain, we review prominent classification schemes that have been proposed to introduce systematicity into the scientific study of ASCs. The reviewed ASC classification schemes fall into three groups according to the criteria they use for categorization: (1) based on the nature, variety, and intensity of subjective experiences (state-based), including conceptual descriptions and psychometric assessments, (2) based on the technique of induction (method-based), and (3) descriptions of neurophysiological mechanisms of ASCs (neuro/physio-based). By comparing and extending existing classification schemes, we can enhance efforts to identify neural correlates of consciousness, particularly when examining mechanisms of ASC induction and the resulting subjective experiences. Furthermore, an overview of what defining ASC characteristics different authors have proposed can inform future research in the conceptualization and quantification of ASC subjective effects, including the identification of those that might be relevant in clinical research. This review concludes by clustering the concepts from the state-based schemes, which are suggested for classifying ASC experiences. The resulting clusters can inspire future approaches to formulate and quantify the core phenomenology of ASC experiences to assist in basic and clinical research.

Background: Classic psychedelics such as psilocybin and lysergic acid diethylamide are anecdotally associated with the phenomenon of “psychedelic afterglow,” a set of predominantly pleasant, temporary psychological effects reported after the acute effects have subsided. Since post-acute effects are crucial for the therapeutic use of psychedelics, an instrument to systematically assess subacute “afterglow” effects is needed. Aims: To create and validate a questionnaire to quantify the subacute “afterglow” effects of psychedelics. Methods: An international online survey was conducted in English and German. Participants who had consumed a psychedelic ( N = 1323) or another non-psychedelic substance (control group, N = 157) within the past 4 weeks were included. An initial list of 97 items was progressively reduced to 24 items. Results: A 5-factor structure best fit the data and showed high internal consistency. The factors included (1) vitality, (2) transpersonal aspects, (3) inspiration/creativity, (4) interpersonal relationships, and (5) relationship to nature. The final 24-item version of the Afterglow Inventory (AGI) effectively differentiated between the psychedelic group and the control group. The overall AGI score positively correlated with the intensity ( r = 0.165; p < 0.001) and positive valence ( r = 0.251; p < 0.001) of the acute psychedelic effects. Conclusions: The AGI is a novel scale for quantifying positive subacute (“afterglow”) effects of psychedelics. The use of the AGI could lead to a better understanding of the interplay between acute, subacute, and long-term effects of psychedelics. Insights could also be gained into how different substances, dosages, and extra-pharmacological factors, such as psychotherapy, might influence outcomes.

Working memory (WM) supports a range of higher order cognitive functions by enabling the short-term maintenance and manipulation of information through dynamic, distributed neural processes. In parallel to findings from the visual modality, tactile WM engages both sensory and higher-order cortical regions, but the temporal dynamics and functional significance of these areas remain incompletely understood. In this fMRI study, we used multivoxel pattern analysis to investigate how spatial features of tactile stimuli are represented and maintained across a short WM delay period. Our results reveal a dynamic engagement of contralateral primary somatosensory cortex (S1) and anterior superior parietal lobe (SPL) during initial encoding, with a shift toward bilateral posterior SPL involvement during later maintenance. Critically, decoding accuracy in the ipsilateral SPL correlated with individual task performance, suggesting that distinctiveness of WM-related representations in this region supports successful memory retention. These findings shed light on the hierarchical organization and temporal evolution of tactile spatial WM, indicating a transformation from concrete sensory to more abstract, distributed representations across parietal regions, modulated by behavioral demands.

Neuroscientific research has shown that perceptual decision-making occurs in brain regions that are associated with the required motor response. Recent functional magnetic resonance imaging (fMRI) studies that dissociated decisions from coinciding processes, such as the motor response, partly challenge this, indicating that perceptual decisions are represented in an abstract or sensory-specific manner that might vary across sensory modalities. However, comparisons across sensory modalities have been difficult since most task designs differ not only in modality but also in effectors, motor response, and level of abstraction. Here, we describe an fMRI experiment where participants compared frequencies of two sequentially presented visual flicker stimuli in a delayed match-to-comparison task, which controlled for motor responses and stimulus sequence. A whole-brain searchlight support vector machine analysis of multi voxel patterns was used to identify brain regions containing information on perceptual decisions. Furthermore, a conjunction analysis with data from an analogue vibrotactile study was conducted for a comparison between visual and tactile decision-making processes. Both analyses revealed above-chance decoding accuracies in the left dorsal premotor cortex (PMd) as well as in the left intraparietal sulcus (IPS). While previous primate and human imaging research have implicated these regions in transforming sensory information into action, our findings indicate that the IPS processes abstract decision signals while the PMd represents an effector-dependent, but motor response independent encoding of perceptual decisions that is similar across sensory domains.

Previous functional magnetic resonance imaging (fMRI) studies have shown that activity in premotor and parietal brain-regions covaries with the intensity of upcoming grip-force. However, it remains unclear how information about the intended grip-force intensity is initially represented and subsequently transformed into a motor code before motor execution. In this fMRI study, we used multivoxel pattern analysis (MVPA) to decode where and when information about grip-force intensities is parametrically coded in the brain. Human participants performed a delayed grip-force task in which one of four cued levels of grip-force intensity had to be maintained in working memory (WM) during a 9-s delay-period preceding motor execution. Using time-resolved MVPA with a searchlight approach and support vector regression, we tested which brain regions exhibit multivariate WM codes of anticipated grip-force intensities. During the early delay period, we observed above-chance decoding in the ventromedial prefrontal cortex (vmPFC). During the late delay period, we found a network of action-specific brain regions, including the bilateral intraparietal sulcus (IPS), left dorsal premotor cortex (l-PMd), and supplementary motor areas. Additionally, cross-regression decoding was employed to test for temporal generalization of activation patterns between early and late delay periods with those during cue presentation and motor execution. Cross-regression decoding indicated temporal generalization to the cue period in the vmPFC and to motor-execution in the l-IPS and l-PMd. Together, these findings suggest that the WM representation of grip-force intensities undergoes a transformation where the vmPFC encodes information about the intended grip-force, which is subsequently converted into a motor code in the l-IPS and l-PMd before execution.

Exposure to rapid and bright stroboscopic light has long been reported to induce vivid visual hallucinations of colour and geometric formations. This phenomenon was first documented by Purkinje over 200 years ago. Since then, significant progress has been made in understanding the effects of stroboscopic light and the experiences it induces through multiple waves of interest from the scientific, therapeutic, and broader cultural communities. Despite these advances, fundamental questions remain unanswered, including comprehensive characterisations of its phenomenology, its precise physiological origins, under which conditions it may lead to altered states of consciousness phenomena, and potential clinical or therapeutic applications. This narrative review provides a historical summary of research into stroboscopic light stimulation alongside its use in recreation and lay-therapeutic contexts. It also discusses the phenomenology of these experiences, current perspectives on the potential neural mechanisms of stroboscopically induced experiences, and provides an outlook for future research in this field.

In this interview, Timo Torsten Schmidt provides details about his efforts to compile a comprehensive database of all psychometric measures gathered from controlled experiments investigating altered states of consciousness (ASCs) induced by pharmacological and non-pharmacological methods. He also introduces the paradigm of Phenomenoconnectomics which aims to systematically investigate the phenomenology and functional connectivity of ASCs to identify commonalities and differences, to ultimately identify the necessary neuronal correlates of specific experiences as they occur during ASCs. He explains some key findings of his own neuroscientific research on the neural correlates of consciousness under the influence of non-pharmacological manipulations, such as Ganzfeld exposure and flicker light stimulation-induced visual illusory percepts. Finally, we touch upon the current limitations of psychometric methods in their ability to capture the full diversity of the phenomenal space and future plans to overcome these caveats through Open Science initiatives that support harm reduction efforts.

Although Virtual Reality (VR) has undoubtedly improved human interaction with 3D data, users still face difficulties retaining important details of complex digital objects in preparation for physical tasks. To address this issue, we evaluated the potential of visuohaptic integration to improve the memorability of virtual objects in immersive visualizations. In a user study (N=20), participants performed a delayed match-to-sample task where they memorized stimuli of visual, haptic, or visuohaptic encoding conditions. We assessed performance differences between these encoding modalities through error rates and response times. We found that visuohaptic encoding significantly improved memorization accuracy compared to unimodal visual and haptic conditions. Our analysis indicates that integrating haptics into immersive visualizations enhances the memorability of digital objects. We discuss its implications for the optimal encoding design in VR applications that assist professionals who need to memorize and recall virtual objects in their daily work.

Flicker light stimulation (FLS) is a non-pharmacological method of inducing altered states of consciousness (ASCs), producing hallucination-like phenomena as well as effects extending beyond the visual modality, including emotional effects. Research into the psychological and neural mechanisms of FLS is still in its infancy, but can be informed by research into other methods of inducing ASCs. For instance, research on classic psychedelics has reported enhancement of emotional responses to music. Here, we test to what degree FLS might also enhance the emotional response to music, using a study protocol designed to resemble a previous study on the effects of LSD as closely as possible, to allow for comparison of effect sizes across modalities and inform future research into FLS as an ASC-induction method. Twenty participants listened to emotionally evocative music in two conditions – with and without FLS – and reported on their emotional response to the music. FLS showed a significant enhancing effect on reported music-evoked emotion, especially emotions relating to “Joyful Activation”; additionally, we found that the experienced intensity of FLS correlated with reports of higher levels of emotional arousal. These findings motivate further research into FLS as a method for inducing ASCs and into the interactions between visual phenomena and music-evoked emotion.

Femtosecond laser excitation of materials exhibiting magnetic spin textures promises advanced magnetic control via the generation of non-equilibrium spin dynamics. Ferrimagnetic [Fe(0.35 nm)/Gd(0.40 nm)]160 multilayers are used to explore this approach, as they host a rich diversity of magnetic textures from stripe domains at low magnetic fields, a dense bubble/skyrmion lattice at intermediate fields, and a single domain state for high magnetic fields. Using femtosecond magneto-optics, distinct coherent spin wave dynamics are observed in this material in response to a weak laser excitation, enabling an unambiguous identification of the different magnetic spin textures. Moreover, employing strong laser excitation, versatile control of the coherent spin dynamics via non-equilibrium transformation of magnetic spin textures becomes possible by both creating and annihilating bubbles/skyrmions. Micromagnetic simulations and Lorentz transmission electron microscopy with in situ optical excitation corroborate these findings. The coherent magneto-optical response of [Fe(0.35 nm)/Gd(0.40 nm)]160 multilayers to weak femtosecond laser excitation is shown to depend on the underlying magnetic spin texture (stripe domains, bubbles, and skyrmions, single domain state). Strong laser excitation can transform these spin textures and, in this way, the coherent response of the spin system can be controlled. image

Haptic feedback reportedly enhances human interaction with 3D data, particularly improving the retention of mental representations of digital objects in immersive settings. However, the effectiveness of visuohaptic integration in promoting object retention across different display environments remains underexplored. Our study extends previous research on the retention effects of haptics from virtual reality to a projected surface display to assess whether earlier findings generalize to 2D environments. Participants performed a delayed match-to-sample task incorporating visual, haptic, and visuohaptic sensory feedback within a projected surface display environment. We compared error rates and response times across these sensory modalities and display environments. Our results reveal that visuohaptic integration significantly enhances object retention on projected surfaces, benefiting task performance across display environments. Our findings suggest that haptics can improve object retention without requiring fully immersive setups, offering insights for the design of interactive systems that assist professionals who rely on precise mental representations of digital objects.

Controlling the dynamics of topologically protected spin objects by all optical means promises enormous potential for future spintronic applications. Excitation of bubbles and skyrmions in ferrimagnetic [Fe(0.35 nm)/Gd(0.40 nm)]$_{160}$ multilayers by ultrashort laser pulses leads to a periodic modulation of the core diameter of these spin objects, the so-called breathing mode. We demonstrate versatile amplitude and phase control of this breathing using a double excitation scheme, where the observed dynamics is controlled by the excitation delay. We gain insight into both the time scale on which the breathing mode is launched and the role of the spin object size on the dynamics. Our results demonstrate that ultrafast optical excitation allows for precise tuning of the spin dynamics of trivial and non-trivial spin objects, showing a possible control strategy in device applications.

The open data initiative Altered States Database (ASDB) collects psychometric questionnaire data on the subjective experiences of pharmacologically and non-pharmacologically induced altered states of consciousness. The ASDB is updated yearly and can be utilized by both researchers and non-scientists to access information or undertake further work on the data. The current update adds data published in the year 2023, taken from a systematic literature review adhering to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A total of 454 items were screened, resulting in 13 included journal articles, of which ten report on the 11-Altered States of Consciousness Rating Scale (11-ASC), eight on the 5D-ASC, six on the Mystical Experience Questionnaire (MEQ-30), and one on the Phenomenology of Consciousness Inventory (PCI). Cumulatively, the ASDB now contains data on 22 substances and 13 techniques to induce altered states (plus control substances/techniques), incorporating 198 journal articles and 847 single datasets. The ASDB can be accessed on www.asdb.info and on Open Science Framework (OSF; https://osf.io/8mbru).

Background: Classic psychedelics such as psilocybin and LSD are anecdotally associated with the phenomenon of "psychedelic afterglow," a set of predominantly pleasant, temporary psychological effects reported after the acute effects have subsided. Since post-acute effects are crucial for the therapeutic use of psychedelics, an instrument to systematically assess subacute "afterglow" effects is needed. Aims: To create and validate a questionnaire to quantify subacute "afterglow" effects of psychedelics. Methods: An international online survey was conducted in English and German. Participants who had consumed a psychedelic (N = 1,323) or another non-psychedelic substance (control group, N = 157) within the past four weeks were included. An initial list of 97 items was progressively reduced to 24 items. Results: A 5-factor structure best fit the data and showed high internal consistency. The factors included 1) Vitality, 2) Transpersonal Aspects, 3) Inspiration/Creativity, 4) Interpersonal Relationships, and 5) Relationship to Nature. The final 24-item version of the Afterglow Inventory (AGI) effectively differentiated between the psychedelic group and the control group. The overall AGI score positively correlated with the intensity (r = 0.165; p &lt; 0.001) and positive valence (r = 0.251; p &lt; 0.001) of the acute psychedelic effects. Conclusions: The AGI is a novel scale for quantifying positive subacute ("afterglow") effects of psychedelics. The use of the AGI could lead to a better understanding of the interplay between acute, subacute, and long-term effects of psychedelics. Insights could also be gained into how different substances, dosages, and extra-pharmacological factors, such as psychotherapy, might influence outcomes.