Stockholm university logo, link to start page

Jonas OlofssonProfessor

About me

My research and teaching involves perception, memory and emotion, with a focus on how the sense of smell, olfaction, affects these processes. My research team investigates whether olfaction provides an early marker for dementia, why it is so hard to name smells, if smell-based video games can be used for brain training, and how odors might affect social processes. To address these issues, we use a variety of behavioral and brain activity methods. For an updated list of publications and citations, please visit my Google Scholar page.


I received my PhD in 2008 at Umeå University and was appointed as docent at Stockholm University in 2009. I conducted research at Northwestern University (Chicago, 2009-2011), The Scripps Research Institute (San Diego, 2005-2006) and at Karolinska Insitutet (Stockholm, 2009). Since 2012, I am affiliated with The Swedish Collegium for Advanced Study in Uppsala. Since 2016, I am adjunct associate professor at New York University School of Medicine. My research is supported by the Swedish Research Council, The Swedish Foundation for Humanities and Social Sciences, and by the Marianne and Marcus Wallenberg Foundation.


Odor identification in aging and dementia: Influences of cognition and the ApoE gene. Doctoral dissertation from the Department of Psychology, Umeå University. ISBN 978-91-7264-652-0

Awards and honors

Elected in 2021 as member of Academia Europaea, a scientific academy with the purpose of facilitating excellence in research and education in Eurrope. Members are nominated and evaluated based on their contributions to research in their respective fields.

Wallenberg Academy Fellow (since 2016), a carreer programme that provides long-term funding for the most promising young researchers of all disciplines.

Fellow of the Young Academy of Sweden (since 2015), an independent, cross-disciplinary forum for some of the most promising young researchers in Sweden across all academic disciplines.

Fellow of Pro Futura Scientia (since 2012), a research programme for especially promising young researchers in the humanities and social sciences.

Recipient of the 2010 prize to young researchers in Psychology by the Swedish National Committee for Psychological Sciences (a branch of the Royal Swedish Academy of Sciences) after receiving nominations from Umeå and Stockholm Universities.

The Fulker award (2009) for best article in the journal Behavior Genetics:
Olofsson, J.K., Rönnlund, M., Nordin, S., Nilsson, L-G., Nyberg, L., & Larsson, M. (2009). Odor identification deficit as a predictor of five-year global cognitive change: Interactive effects with age and ApoE-e4. Behavior Genetics, 39, 496-503.

Research projects


A selection from Stockholm University publication database

  • A Review of the Effects of Valenced Odors on Face Perception and Evaluation

    2021. Elmeri Syrjänen (et al.). i-Perception 12 (2), 1-19


    How do valenced odors affect the perception and evaluation of facial expressions? We reviewed 25 studies published from 1989 to 2020 on cross-modal behavioral effects of odors on the perception of faces. The results indicate that odors may influence facial evaluations and classifications in several ways. Faces are rated as more arousing during simultaneous odor exposure, and the rated valence of faces is affected in the direction of the odor valence. For facial classification tasks, in general, valenced odors, whether pleasant or unpleasant, decrease facial emotion classification speed. The evidence for valence congruency effects was inconsistent. Some studies found that exposure to a valenced odor facilitates the processing of a similarly valenced facial expression. The results for facial evaluation were mirrored in classical conditioning studies, as faces conditioned with valenced odors were rated in the direction of the odor valence. However, the evidence of odor effects was inconsistent when the task was to classify faces. Furthermore, using a z-curve analysis, we found clear evidence for publication bias. Our recommendations for future research include greater consideration of individual differences in sensation and cognition, individual differences (e.g., differences in odor sensitivity related to age, gender, or culture), establishing standardized experimental assessments and stimuli, larger study samples, and embracing open research practices.

    Read more about A Review of the Effects of Valenced Odors on Face Perception and Evaluation
  • Olfactory Language

    2021. Jonas K. Olofsson, Stephen Pierzchajlo. Trends in cognitive sciences 25 (6), 419-420


    The sense of smell, olfaction, is currently in the spotlight. Although often a neglected sense, smell loss and smell distortions due to coronavirus disease 2019 (COVID-19) has increased public awareness of olfaction and its role in health, well-being, and nutrition. In this unusual context, Majid provides a timely, well written, and thought-provoking review of olfaction and its cognitive aspects. Majid focuses on how smells are expressed in languages around the world, yet the review covers a vast literature that includes also experimental, cognitive, and biological fields. The thrust of the argument is directed against a perceived dogma; that ‘there is no language of smell and humans are bad at naming odors’. Majid argues that this dogma is refuted by cross-cultural research and concludes that ‘rather than focusing on constrained experimental tasks’, olfactory language should be studied in terms of ‘how people across the globe use, manipulate and talk about odors in their day-to-day contexts’. Later, we show how empirical and theoretical considerations lead us to partly different conclusions. Empirically, we believe that odor naming remains poorer than naming in other senses and that careful laboratory experiments will remain critical for understanding olfactory-based language and cognition. Toward this goal, we emphasize the distinction between multisensory and unisensory olfaction, which is not highlighted in Majid's review but which we believe is of theoretical importance.

    Read more about Olfactory Language
  • To which world regions does the valence–dominance model of social perception apply?

    2021. Benedict C. Jones (et al.). Nature Human Behaviour 5 (1), 159-169


    Over the past 10 years, Oosterhof and Todorov’s valence–dominance model has emerged as the most prominent account of how people evaluate faces on social dimensions. In this model, two dimensions (valence and dominance) underpin social judgements of faces. Because this model has primarily been developed and tested in Western regions, it is unclear whether these findings apply to other regions. We addressed this question by replicating Oosterhof and Todorov’s methodology across 11 world regions, 41 countries and 11,570 participants. When we used Oosterhof and Todorov’s original analysis strategy, the valence–dominance model generalized across regions. When we used an alternative methodology to allow for correlated dimensions, we observed much less generalization. Collectively, these results suggest that, while the valence–dominance model generalizes very well across regions when dimensions are forced to be orthogonal, regional differences are revealed when we use different extraction methods and correlate and rotate the dimension reduction solution.

    Read more about To which world regions does the valence–dominance model of social perception apply?
  • A Method for Computerized Olfactory Assessment and Training Outside of Laboratory or Clinical Settings

    2021. Simon Niedenthal (et al.). i-Perception 12 (3), 1-12


    There are currently few ways to reliably and objectively assess olfaction outside of the research laboratory or clinic. The COVID-19 pandemic has highlighted the need for remote olfactory assessment; in particular, smell training at home is a promising method for olfactory rehabilitation, but further methodological advances might enhance its effectiveness and range of use. Here, we present Exerscent, a portable, low-cost olfactory display designed primarily for uses outside of the laboratory and that can be operated with a personal computer. Exerscent includes Radio Frequency Identification (RFID) tags that are attached to odor stimuli and read with a MFRC522 module RFID reader/antenna that encodes the odor in order to provide adaptive challenges for the user (e.g., an odor identification task). Hardware parts are commercially available or 3D printed. Instructions and code for building the Exerscent are freely available online ( As a proof of concept, we present a case study in which a participant trained daily to identify 54 odors, improving from 81% to 96% accuracy over 16 consecutive days. In addition, results from a laboratory experiment with 11 volunteers indicated a very high level of perceived usability and engagement. Exerscent may be used for olfactory skills development (e.g., perfumery, enology), and rehabilitation purposes (e.g., postviral olfactory loss), but it also allows for other forms of technological interactions such as olfactory-based recreational interactions.

    Read more about A Method for Computerized Olfactory Assessment and Training Outside of Laboratory or Clinical Settings
  • A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic

    2021. Ke Wang (et al.). Nature Human Behaviour 5 (8), 1089-1110


    The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world.

    Read more about A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic
  • Duality of Smell

    2021. Robert Pellegrino (et al.). Chemical Senses 46, 1-11


    Olfactory research in humans has largely focused on odors perceived via sniffing, orthonasal olfaction, whereas odors perceived from the mouth, retronasal olfaction, are less well understood. Prior work on retronasally presented odors involves animal models and focus mainly on odor sensitivity, but little is known about retronasal olfactory perception and cognition in humans. In this study, we compared orthonasal and retronasal odor presentation routes to investigate differences in odor descriptions and evaluations. Thirty-six individuals participated in a within-subjects study using twelve odors (varying in pleasantness and edibility) in perceptual and semantic tasks. Orthonasal presentation was associated with a better ability to identify odors, and with more concrete (and source-based) language. Exploratory analyses revealed that whereas orthonasal odors were described with words that had visual associations, retronasal odors were described with words that had interoceptive associations. Interestingly, these route-dependent differences in descriptor usage were not explained by differences in sensitivity and intensity, suggesting instead a cognitive and linguistic processing difference between odors presented orthonasally and retronasally. Our results indicate that olfaction is, in fact, a dual sense, in which the routes change the perception of an odor.

    Read more about Duality of Smell
  • Human hippocampal connectivity is stronger in olfaction than other sensory systems

    2021. Guangyu Zhou (et al.). Progress in Neurobiology 201


    During mammalian evolution, primate neocortex expanded, shifting hippocampal functional networks away from primary sensory cortices, towards association cortices. Reflecting this rerouting, human resting hippocampal functional networks preferentially include higher association cortices, while those in rodents retained primary sensory cortices. Research on human visual, auditory and somatosensory systems shows evidence of this rerouting. Olfaction, however, is unique among sensory systems in its relative structural conservation throughout mammalian evolution, and it is unknown whether human primary olfactory cortex was subject to the same rerouting. We combined functional neuroimaging and intracranial electrophysiology to directly compare hippocampal functional networks across human sensory systems. We show that human primary olfactory cortex—including the anterior olfactory nucleus, olfactory tubercle and piriform cortex—has stronger functional connectivity with hippocampal networks at rest, compared to other sensory systems. This suggests that unlike other sensory systems, olfactory-hippocampal connectivity may have been retained in mammalian evolution. We further show that olfactory-hippocampal connectivity oscillates with nasal breathing. Our findings suggest olfaction might provide insight into how memory and cognition depend on hippocampal interactions.

    Read more about Human hippocampal connectivity is stronger in olfaction than other sensory systems
  • Joint trajectories of episodic memory and odor identification in older adults

    2021. Christina S. Dintica (et al.). Aging 13 (13), 17080-17096


    Emerging evidence suggests that olfactory function is closely linked to memory function. The aims of this study were to assess whether olfactory and episodic memory functions follow similar age-related decline trajectories, to identify different patterns of decline, as well as predictors of the patterns. 1023 participants from the Memory and Aging Project were followed for up to 8 years with annual episodic memory and odor identification assessments. Trajectories were modelled using growth mixture models. Multivariate logistic regression was used to identify pattern predictors. Three patterns of joint trajectories were identified; Class 1- stable average performance in both functions (n=690, 67.4%); Class 2- stable average episodic memory and declining odor identification (n=231, 22.6%); and Class 3- decline in both functions (n=102, 10.0%). Class predictors included age, sex, APOE epsilon 4 status, cognitive activity level and BMI. Participants in Class 3 were most likely to develop dementia. Episodic memory and olfactory function show similar trajectories in aging. Such classification can contribute to a better understanding of the factors related to cognitive decline and dementia.

    Read more about Joint trajectories of episodic memory and odor identification in older adults
  • Olfaction and Aging

    2021. Jonas K. Olofsson (et al.). i-Perception 12 (3), 1-24


    Olfaction, the sense of smell, is characterized by a notable age-dependency such that aging individuals are more likely to have poor olfactory abilities. These impairments are considered to be mostly irreversible and as having potentially profound effects on quality of life and food behavior, as well as constituting warning signs of mortality, cognitive dysfunction, and dementia. Here, we review the current state of research on aging and olfaction, focusing on five topics which we regard to be of particular relevance for the field: nutrition and health, cognition and dementia, mortality, environment and genetics, and training-based enhancement. Under each of these headlines, we provide a state-of-the-art overview and discuss gaps in our knowledge which might be filled by further research. Understanding how olfactory abilities are diminished in aging, and how they may be alleviated or recovered, involves a set of challenging tasks for researchers in the years to come.

    Read more about Olfaction and Aging
  • Recent Smell Loss Is the Best Predictor of COVID-19 Among Individuals With Recent Respiratory Symptoms

    2021. Richard C. Gerkin (et al.). Chemical Senses 46, 1-12


    In a preregistered, cross-sectional study, we investigated whether olfactory loss is a reliable predictor of COVID-19 using a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0–100 visual analog scales (VAS) for participants reporting a positive (C19+; n = 4148) or negative (C19−; n = 546) COVID-19 laboratory test outcome. Logistic regression models identified univariate and multivariate predictors of COVID-19 status and post-COVID-19 olfactory recovery. Both C19+ and C19− groups exhibited smell loss, but it was significantly larger in C19+ participants (mean ± SD, C19+: −82.5 ± 27.2 points; C19−: −59.8 ± 37.7). Smell loss during illness was the best predictor of COVID-19 in both univariate and multivariate models (ROC AUC = 0.72). Additional variables provide negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms (e.g., fever). Olfactory recovery within 40 days of respiratory symptom onset was reported for ~50% of participants and was best predicted by time since respiratory symptom onset. We find that quantified smell loss is the best predictor of COVID-19 amongst those with symptoms of respiratory illness. To aid clinicians and contact tracers in identifying individuals with a high likelihood of having COVID-19, we propose a novel 0–10 scale to screen for recent olfactory loss, the ODoR-19. We find that numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (4 < OR < 10). Once independently validated, this tool could be deployed when viral lab tests are impractical or unavailable.

    Read more about Recent Smell Loss Is the Best Predictor of COVID-19 Among Individuals With Recent Respiratory Symptoms

Show all publications by Jonas Olofsson at Stockholm University