Publications

Abstract: Skin conductance response (SCR) serves as a dependable marker of sympathetic activation used to measure emotional arousal. This study investigates the impact of presentation modality (face or word) on the degree of emotional discrimination elicited by SCR. Facial expressions or words associated with six basic emotions—anger, happiness, disgust, fear, sadness, and surprise—were studied among 102 participants. The amplitude of SCR was accurately predicted by subjective arousal ratings of these stimuli, but not by valence ratings. The habituation process to emotional and neutral stimuli across six successive presentations was characterized by an exponential decay function, capturing the rate at which SCR response diminishes in relation to the preceding trial of the same stimulus. Through the subtraction of the response to neutral stimuli from the emotion evoked SCR, it was demonstrated that the initial presentation of each emotion elicits a substantial response, particularly attributable to the emotional content. Notably, the initial emotional response to faces expressing happiness, disgust, and sadness surpassed that of words conveying the same emotions. The results indicate that different emotional responses can be quantified using a simple electrical instrument.
 
Citation: Juuse, L., Tamm, D., Lõo, K., Allik, J., & Kreegipuu, K. (2024). Skin conductance response and habituation to emotional facial expressions and words. Acta Psychologica, 251, 104573. https://doi.org/10.1016/j.actpsy.2024.104573
 
This article was supported by Estonian Research Council teamgrant PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025) and “Estonian Center of Excellence of Well-Being Sciences” TK218 funded by Ministry of Education and Research.

Abstract: Estonian is a quantity language with both a primary duration cue and a secondary pitch cue, whereas Chinese is a tonal language with a dominant pitch use. Using a mismatch negativity experiment and a behavioral discrimination experiment, we investigated how native language background affects the perception of duration only, pitch only, and duration plus pitch information. Chinese participants perceived duration in Estonian as meaningless acoustic information due to a lack of phonological use of duration in their native language; however, they demonstrated a better pitch discrimination ability than Estonian participants. On the other hand, Estonian participants outperformed Chinese participants in perceiving the non-speech pure tones that resembled the Estonian quantity (i.e., containing both duration and pitch information). Our results indicate that native language background affects the perception of duration and pitch and that such an effect is not specific to processing speech sounds.
 
Citation: Lyu, S., Põldver, N., Kask, L., Wang, L., & Kreegipuu, K. (2024). Native language background affects the perception of duration and pitch. Brain and Language, 256, 105460. https://doi.org/10.1016/j.bandl.2024.105460
 
This article was supported by Estonian Research Council teamgrants PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025) and MOBJD662 “Effect of linguistic and musical experience on the processing of language in the brain” (2021-2022) and the National Social Sience Fund of China (grant number 23BYY045).

Abstract: This study adopts a cross-linguistic perspective and investigates how musical expertise affects the perception of duration and pitch in language. Native speakers of Chinese (N = 44) and Estonian (N = 46), each group subdivided into musicians and non-musicians, participated in a mismatch negativity (MMN) experiment where they passively listened to both Chinese and Estonian stimuli, followed by a behavioral experiment where they attentively discriminated the stimuli in the non-native language (i.e., Chinese to Estonian participants and Estonian to Chinese participants). In both experiments, stimuli of duration change, pitch change, and duration plus pitch change were discriminated. We found higher behavioral sensitivity among Chinese musicians than non-musicians in perceiving the duration change in Estonian and higher behavioral sensitivity among Estonian musicians than non-musicians in perceiving all types of changes in Chinese, but no corresponding effect was found in the MMN results, which suggests a more salient effect of musical expertise on foreign language processing when attention is required. Secondly, Chinese musicians did not outperform non-musicians in attentively discriminating the pitch-related stimuli in Estonian, suggesting that musical expertise can be overridden by tonal language experience when perceiving foreign linguistic pitch, especially when an attentive discrimination task is administered. Thirdly, we found larger MMN among Chinese and Estonian musicians than their non-musician counterparts in perceiving the largest deviant (i.e., duration plus pitch) in their native language. Taken together, our results demonstrate a positive effect of musical expertise on language processing.

Citation: Lyu, S., Põldver, N., Kask, L., Wang, L., & Kreegipuu, K. (2024). Effect of musical expertise on the perception of duration and pitch in language: a cross-linguistic study. Acta Psychologica, 244, 104195. https://doi.org/10.1016/j.actpsy.2024.104195

This article was supported by Estonian Research Council teamgrants PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025) and MOBJD662 “Effect of linguistic and musical experience on the processing of language in the brain” (2021-2022) and the National Social Sience Fund of China (grant number 23BYY045).

Abstract: It has become popular to demonstrate that the specific variance can make a substantial contribution to accurate personality judgements. This study challenges the main assumption that transformation of manifest scores into residual scores is capable of separating the specific from the common variance. Based on two  large samples (N = 11,086), in which participants and their well-acquainted observers completed either the NEO-PI-3 or the HEXACO-PI-R personality inventory, we demonstrated that the residual scores still contain a substantial amount of the common variance, which inflates correlations with criterion variables. An alternative method using multiple regression showed that different forms of residual scores have a modest incremental improvement of explained variance beyond the effects of the common variance contained in the manifest scores. On average, the specific variance improves the self-other agreement less than 4% consequently having a marginal effect on accurate personality judgments.

Citation: Allik, J., Realo, A., & de Vries, R. E. (2024). Elusive specific variance: a marginal effect on the accuracy of personality judgment. Journal of Research in Personality, 109, 104464. https://doi.org/10.1016/j.jrp.2024.104464

This article was supported by Estonian Research Council teamgrant PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025). Anu Realo was a KONE Foundation Fellow at the Helsinki Collegium for Advanced Studies during the preparation of this manuscript in Spring 2023.

Abstract: While research has shown that wearing a disguise hinders lineup identifications, less is known about how to conduct lineups in cases of disguised perpetrators. We examined the influence of surgical masks, worn during a crime event (encoding) and within lineups (retrieval), on eyewitness identification accuracy. In our experiment, 452 participants watched a mock-crime video and identified the perpetrator from either a target-present or a target-absent simultaneous lineup. Contrary to expectations based on the encoding specificity principle, we did not find that matching the presence of masks in the lineup to the encoding condition increased identification accuracy. Instead, compared to the condition with no masks at encoding and retrieval, the presence of masks at either stage negatively affected discriminability and undermined the predictive utility of confidence and decision time. Our findings indicate that when a witness has encountered a masked perpetrator, presenting them with a masked lineup may not be necessary.

Citation: Palu, A., Raidvee, A., Murnikov, V., & Kask, K. (2023). The effect of surgical masks on identification decisions from masked and unmasked lineups. Psychiatry, Psychology and Law, 1-31. https://doi.org/10.1080/13218719.2023.2242435

This article was supported by Estonian Research Council teamgrant PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025).

Abstract: Event-related potentials (ERPs), specifically the Mismatch Response (MMR), holds promise for investigating auditory maturation in children. It has the potential to predict language development and distinguish between language-impaired and typically developing groups. However, summarizing the MMR’s developmental trajectory in typically developing children remains challenging despite numerous studies. This pioneering meta-analysis outlines changes in MMR amplitude among typically developing children, while offering methodological best-practices. Our search identified 51 articles for methodology analysis and 21 for meta-analysis, involving 0–8-year-old participants from 2000 to 2022. Risk of Bias assessment and methodology analysis revealed shortcomings in control condition usage and reporting of study confounders. The meta-analysis results were inconsistent, indicating large effect sizes in some conditions and no effect sizes in others. Subgroup analysis revealed the main effects of age and brain region, as well as an interaction of age and time-window of the MMR. Future research requires a specific protocol, larger samples, and replication studies to deepen the understanding of the auditory discrimination maturation process in children.

Citation: Themas, L., Lippus, P., Padrik, M., Kask, L., & Kreegipuu, K. (2023). Maturation of the mismatch response in pre-school children: Systematic literature review and meta-analysis. Neuroscience & Biobehavioral Reviews, 153, 105366. https://doi.org/10.1016/j.neubiorev.2023.105366

This article was supported by Estonian Research Council teamgrant PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025).

Abstract: Affective aspects of a stimulus can be processed rapidly and before cognitive attribution, acting much earlier for verbal stimuli than previously considered. Aimed for specific mechanisms, event-related brain potentials (ERPs), expressed in facial expressions or word meaning and evoked by six basic emotions – anger, disgust, fear, happy, sad, and surprise – relative to emotionally neutral stimuli were analysed in a sample of 116 participants. Brain responses in the occipital and left temporal regions elicited by the sadness in facial expressions or words were indistinguishable from responses evoked by neutral faces or words. Confirming previous findings, facial fear elicited an early and strong posterior negativity. Instead of expected parietal positivity, both the happy faces and words produced significantly more negative responses compared to neutral. Surprise in facial expressions and words elicited a strong early response in the left temporal cortex, which could be a signature of appraisal. The results of this study are consistent with the view that both types of affective stimuli, facial emotions and word meaning, set off rapid processing and responses occur very early in the processing stage.

Citation: Juuse, L., Kreegipuu, K., Põldver, N., Kask, A., Mogom, T., Anbarjafari, G., & Allik, J. (2023). Processing emotions from faces and words measured by event-related brain potentials. Cognition and Emotion, 37:5, 959-972, https://doi.org/10.1080/02699931.2023.2223906

This article was supported by Estonian Research Council grant IUT2-13 “Psychological mechanisms of cognition and personality processes”, PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025) and PUT638 “Enhancing human-computer interaction using multimodal emotion recognition based on gesture, face, and speech”.

Abstract: Culture-and-personality studies were central to social science in the early 20th century and have recently been revived (as personality-and-culture studies) by trait and cross-cultural psychologists. In this article we comment on conceptual issues, including the nature of traits and the nature of the personality-and-culture relationship, and we describe methodological challenges in understanding associations between features of culture and aspects of personality. We give an overview of research hypothesizing the shaping of personality traits by culture, reviewing studies of indigenous traits, acculturation and sojourner effects, birth cohorts, social role changes, and ideological interventions. We also consider the possibility that aggregate traits affect culture, through psychological means and gene flow. In all these cases we highlight alternative explanations and the need for designs and analyses that strengthen the interpretation of observations. We offer a set of testable hypotheses based on the premises that personality is adequately described by Five-Factor Theory, and that observed differences in aggregate personality traits across cultures are veridical. It is clear that culture has dramatic effects on the thoughts, feelings, and behaviors from which we infer traits, but it is not yet clear whether, how, and in what degree culture shapes traits themselves.

Citation: Allik, J., Realo, A., & McCrae, R. R. (2023). Conceptual and methodological issues in the study of the personality-and-culture relationship. Frontiers in psychology, 14, 1077851. https://doi.org/10.3389/fpsyg.2023.1077851

This article was supported by Estonian Research Council teamgrant PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025).

Abstract: The low reproducibility rate in social sciences has produced hesitation among researchers in accepting published findings at their face value. Despite the advent of initiatives to increase transparency in research reporting, the field is still lacking tools to verify the credibility of research reports. In the present paper, we describe methodologies that let researchers craft highly credible research and allow their peers to verify this credibility. We demonstrate the application of these methods in a multi-laboratory replication of Bem’s Experiment 1 (Bem 2011 J. Pers. Soc. Psychol. 100, 407–425. (doi:10.1037/a0021524)) on extrasensory perception (ESP), which was co-designed by a consensus panel including both proponents and opponents of Bem’s original hypothesis. In the study we applied direct data deposition in combination with born-open data and real-time research reports to extend transparency to protocol delivery and data collection. We also used piloting, checklists, laboratory logs and video-documented trial sessions to ascertain as-intended protocol delivery, and external research auditors to monitor research integrity. We found 49.89% successful guesses, while Bem reported 53.07% success rate, with the chance level being 50%. Thus, Bem’s findings were not replicated in our study. In the paper, we discuss the implementation, feasibility and perceived usefulness of the credibility-enhancing methodologies used throughout the project.

Citation: Kekecs, L., Palfi, B., Szaszi, B., Szecsi, P., Zrubka, M., Kovacs, M., Bakos, B.E., Cousineau, D., Tressoldi, P.,  Schmidt, K., Grassi, M., Evans, T.R., Yamada, Y., Miller, J.K., Liu, H., Yonemitsu, F., Dubrov, D., Röer, J.P., Becker, M., Schnepper, R., Ariga, A., Arriaga, P., Oliveira, R., Põldver, N., Kreegipuu, K., Hall, B., Wiechert, S., Verschuere, B., Girán, K., & Aczel B. (2023) Raising the value of research studies in psychological science by increasing the credibility of research reports: the transparent Psi project. R. Soc. Open Sci. 10,191375. https://doi.org/10.1098/rsos.191375

The project was funded by the Bial Foundation via grant no. 122/16. D.D. was supported within the framework of the Basic Research Program at the National Research University Higher School of Economics (HSE University) and a subsidy by the Russian Academic Excellence Project ‘5–100’.

Abstract: Little research has examined age differences by using more than one source of information. We compared age differences in Five-Factor Model (FFM) facets and nuances in self-reports and ratings by knowledgeable informants using samples from three countries (Estonia, Germany, and the Czech Republic; N = 5,624). We hypothesized that age differences would be larger in self- than informant-reports, because of greater social desirability in self-descriptions with advancing age. Indeed, we found that age differences were systematically smaller in informant-reports compared to self-reports; this trend was stronger for traits independently rated as socially desirable. As age differences may be best approximated by average trends of self- and informant-reports, we provide meta-analytic age trends for multi-rater composite scores of the FFM facets and nuances.

Citation: Ausmees, L., Kandler, C., Realo, A., Allik, J., Borkenau, P., Hřebíčková, M., & Mõttus, R. (2022) Age differences in personality traits and social desirability: A multi-rater multi-sample study, Journal of Research in Personality, 99,104245. https://doi.org/10.1016/j.jrp.2022.104245

This article was supported by Estonian Research Council teamgrant PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025).

Abstract: The ability to evaluate the number of elements in a set—numerosity—without symbolic representation is a form of primitive perceptual intelligence. A simple binomial model was proposed to explain how observers discriminate the numerical proportion between two sets of elements distinct in color or orientation (Raidvee et al., 2017, Attention Perception & Psychophysics, 79[1], 267–282). The binomial model’s only parameter β is the probability with which each visual element can be noticed and registered by the perceptual system. Here we analyzed the response times (RT) which were ignored in the previous report since there were no instructions concerning response speed. The relationship between the mean RT and the absolute difference |ΔN| between numbers of elements in two sets was described by a linear regression, the slope of which became flatter as the total number of elements N increased. Because the coefficients of regression between the mean RT and |ΔN| were more directly related to the binomial probability β rather than to the standard deviation of the best fitting cumulative normal distribution, it was regarded as evidence that the binomial model with a single parameter — probability β — is a viable alternative to the customary Thurstonian–Gaussian model.

Citation: Allik, J., Raidvee, A. (2022) How much time does it take to discriminate two sets by their numbers of elements?. Atten Percept Psychophys 84, 1726–1733. https://doi.org/10.3758/s13414-022-02474-7

This article was supported by Estonian Research Council teamgrant PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025). Aire Raidvee was supported by the Mobilitas Pluss Returning Researcher Grant (MOBTP91) by Estonian Research Council.

Abstract: Since 1978, when mismatch negativity (MMN) was reported for the first time in the auditory modality (Näätänen et al., 1978), MMN has been used to investigate automatic change detection. The first reports of visual mismatch negativity (vMMN) were published∼ 20 years after the discovery of the auditory MMN (Tales et al., 1999). Thereafter, vMMN has been used to study basic visual feature processing (Czigler et al., 2002; Astikainen et al., 2008; Grimm et al., 2009) as well as complex visual information processing, mostly face information (Astikainen and Hietanen, 2009; Kreegipuu et al., 2013), in normative and clinical populations (for a review see, Kremlácek et al., 2016). Later, vMMN, as well as its auditory counterpart, has been linked to predictive coding theory (Stefanics et al., 2014), which states that the brain predicts future events based on the representations of previous sensory events (Friston, 2005). This is well in line with the original idea of Risto Näätänen that the MMN reflects a memory-comparison process between the sensory memory of the standards and the “deviant” sensory input (Näätänen, 1990). In predictive coding framework (v) MMN is suggested to reflect prediction error which occurs when the new sensory input does not fit the predicted model (Friston, 2005). Predictive coding is suggested to be aberrant in several psychiatric conditions (for a recent review, see Smith et al., 2021). Therefore, vMMN is an important tool to investigate also predictive mechanisms in neuropsychiatric conditions, and it may have the potential for clinical applications.

Citation: Astikainen, P., Kreegipuu, K., & Czigler, I. (2022). Editorial : Visual mismatch negativity (vMMN): A unique tool in investigating automatic processing. Frontiers in Human Neuroscience, 16, Article 1056208. DOI: 10.3389/fnhum.2022.1056208.

This article was supported by Estonian Research Council teamgrant PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025).

Abstract: The present study investigates how the brain automatically discriminates emotional schematic faces, as indicated by the mismatch responses, and how reliable these brain responses are. Thirty-three healthy volunteers participated in the vMMN EEG experiment with four experimental sets differing from each other by the type of standard (object with scrambled face features) and the type of deviants (Angry, Happy and Neutral schematic faces) presented. Conscious subjective evaluations of valence, arousal and attention catching of the same stimuli showed clear differentiation of emotional expressions. Deviant faces elicited rather similar vMMN at frontal and occipital sites. Bayesian analyses suggest that vMMN does not differ between angry and happy faces. Neutral faces, however, did not yield statistically significant vMMN at occipital leads. Pearson’s correlation and intra-class correlation analyses showed that the brain’s reactions to the stimuli were highly stable within individuals across the experimental sets, whereas the mismatch responses were much more variable.

Citation: Kask, A., Põldver, N., Ausmees, L., & Kreegipuu, K. (2021). Subjectively different emotional schematic faces not automatically discriminated from the brain’s bioelectrical responses. Consciousness and Cognition, 93,  103150. DOI: 10.1016/j.concog.2021.103150.

This article was supported by Estonian Research Council teamgrant PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025).

Abstract: Similar to visual perception, auditory perception also has a clearly described “pop-out” effect, where an element with some extra feature is easier to detect among elements without an extra feature. This phenomenon is better known as auditory perceptual asymmetry. We investigated such asymmetry between shorter or longer duration, and level or falling of pitch of linguistic stimuli that carry a meaning in one language (Estonian), but not in another (Russian). For the mismatch negativity (MMN) experiment, we created four different types of stimuli by modifying the duration of the first vowel [ɑ] (170, 290 ms) and pitch contour (level vs. falling pitch) of the stimuli words (‘SATA,’ ‘SAKI’). The stimuli were synthesized from Estonian words (‘SATA,’ ‘SAKI’) and follow the Estonian language three-way quantity system, which incorporates tonal features (falling pitch contour) together with temporal patterns. This made the meaning of the word dependent on the combination of both features and allows us to compare the relative contribution of duration and pitch contour in discrimination of language stimuli in the brain via MMN generation. The participants of the experiment were 12 Russian native speakers with little or no experience in Estonian and living in Estonia short-term, and 12 Estonian native speakers (age 18–27 years). We found that participants’ perception of the linguistic stimuli differed not only according to the physical features but also according to their native language, confirming that the meaning of the word interferes with the early automatic processing of phonological features. The GAMM and ANOVA analysis of the reversed design results showed that the deviant with longer duration among shorter standards elicited a MMN response with greater amplitude than the short deviant among long standards, while changes in pitch contour (falling vs. level pitch) produced neither strong MMN nor asymmetry. Thus, we demonstrate the effect of language background on asymmetric perception of linguistic stimuli that aligns with those of previous studies (Jaramillo et al., 2000), and contributes to the growing body of knowledge supporting auditory perceptual asymmetry.

Citation: Kask, L., Põldver, N., Lippus, P., & Kreegipuu, K. (2021). Perceptual Asymmetries and Auditory Processing of Estonian Quantities. Frontiers in Human Neuroscience, 15, 612617. DOI: 10.3389/fnhum.2021.612617.

This article was supported by Estonian Research Council teamgrant PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025).

Abstract: Dysregulated eating could be viewed on a continuum, with normal eating behaviour on one end, binge eating on the other end, and overeating in the middle of the continuum. Binge eating refers to consuming an excessive amount of food within a short period of time that is accompanied by a feeling of loss of control over eating. In addititon to over- and binge eating, emotional eating could also be considered a dysregulated eating behaviour. Emotional eating refers to the tendency to eat in response to various negative emotions, usually with an intent to alleviate negative affect. Lately, the concept of positive emotional eating has also emerged, although its relation with eating disorder psyhopathology is unclear. As dysregulated eating behaviours are also seen in community samples and as they represent risk factors for developing an eating disorder, the aim of this doctoral dissertation was to explore the construct of emotional eating, while differentiating between eating in response to positive and negative emotions, and to further investigate their associations with eating pathology and emotion regulation difficulties. We found important similarities as well as differences between positive and negative emotional eating. Namely, eating in response to negative emotions was more closely related to binge eating, general eating pathology, and difficulties with regulating emotions. Positive emotional eating, however, was associated with overeating, which suggests that eating in response to positive emotions might not itself be pathological. However, individuals who endorsed primarily positive emotional eating were characterized by increased difficulties in regulating their impulses and emotions in general compared to individuals without emotional eating. These results indicate that difficulties in managing one’s emotions – be it positive or negative – might be a risk factor for the development and maintenance of dysregulated eating. Interestingly, positive emotional eating appeared to be more pronounced in men, pointing towards important sex differences in emotional eating. In conclusion, we clarified the construct of emotional eating by further confirming that eating in response to negative emotions is an important risk factor for eating disorder psychopathology. We also clarified the role of positive emotions in eating behaviours by showing that its relationship with dysregulated eating is multifaceted and therefore in need of further research.

Citation: Sultson, H. (2022). Refining the constructs of positive and negative emotional eating [Doctoral dissertation, Institute of Psychology, University of Tartu]. http://hdl.handle.net/10062/83834

This Doctoral dissertation was supported by Estonian Research Council teamgrant PRG1151 “Pre-attentive information processing in the brain: relationship to state and trait variables, and behaviour“ (2021-2025).

Abstract: The thesis studies use of psychedelic plant brew ayahuasca. Ayahuasca is traditionally used in Amazonian indigenous rituals and as a sacrament in syncretic religions from Brazil. It is also used over the world in neoshamanic rituals. This interdisciplinary study approached ayahuasca from chemical, psychological and spiritual aspects, also considering sociocultural view. Chemical analyses of 102 brews showed that in indigenous and Santo Daime samples, the amounts of active substances were moderate and correlated with each other. However, in some European neoshamanic brews, the concentrations of psychedelic DMT were high, and traditional plants had been replaced by other plants or chemicals. The study used psychological tests and questionnaires (30 users + 30 controls), and interviews with 63 ayahuasca users. The users who participated in the psychological study were found to be mentally healthy and cognitively normal. As compared to the control group, their depression and anxiety were lower, and satisfaction with life and happiness about life were higher. The spiritual background of the participants was varied and often related to ‘new spirituality’. Ayahuasca rituals were often a part of their spirituality and a source of spiritual experiences. The experiences included e.g. perceptual changes, visionary journeys, healings in the body, contacts with spiritual beings, transformations, and mystical experiences. Some participants had developed an ongoing relationship with the plant as a conscious, sacred, wise and healing spiritual entity. The majority of the participants reported benefits of the practice, but a few described adverse outcomes. Ritual use of ayahuasca has a social dimension. Shared beliefs around the practice are largely rooted in new spirituality. Beliefs affect interpretation of the experience: e.g. suffering during the session is understood as a lesson or message from the sacred plant. Such interpretations help to make sense of the experience. However, some beliefs may restrict interpretations or enable the facilitators of the ceremony to deflect their responsibility. Ritual use of ayahuasca is a challenge to mainstream views about psychoactive substances and their users. The study contributes to the discussion about such practices in the society.

Citation: Kaasik, H. (2022). Sacred medicine from the forest: chemical, psychological and spiritual aspects of ayahuasca [University of Tartu, Faculty of Arts and Humanities, School of Theology and Religious Studies]. http://hdl.handle.net/10062/83274

Citation: Kreegipuu, K., Põldver, N., Krajuškina, M., & Allik, J. (2022). Reliability of visual and auditory MMN. The International Conference of Cognitive Neuroscience (ICON). University of Helsinki, Espoo, Finland, May 18–22, 2022. University of Helsinki, Espoo, Finland.