More than smell - COVID-19 is associated with severe impairment of smell, taste, and chemesthesis

Recent anecdotal and scientific reports have provided evidence of a link between COVID-19 and chemosensory impairments such as anosmia. However, these reports have downplayed or failed to distinguish potential effects on taste, ignored chemesthesis, generally lacked quantitative measurements, were mostly restricted to data from single countries. Here, we report the development, implementation and initial results of a multi-lingual, international questionnaire to assess self-reported quantity and quality of perception in three distinct chemosensory modalities (smell, taste, and chemesthesis) before and during COVID-19. In the first 11 days after questionnaire launch, 4039 participants (2913 women, 1118 men, 8 other, ages 19-79) reported a COVID-19 diagnosis either via laboratory tests or clinical assessment. Importantly, smell, taste and chemesthetic function were each significantly reduced compared to their status before the disease. Difference scores (maximum possible change+/-100) revealed a mean reduction of smell (-79.7+/- 28.7, mean+/- SD), taste (-69.0+/- 32.6), and chemesthetic (-37.3+/- 36.2) function during COVID-19. Qualitative changes in olfactory ability (parosmia and phantosmia) were relatively rare and correlated with smell loss. Importantly, perceived nasal obstruction did not account for smell loss. Furthermore, chemosensory impairments were similar between participants in the laboratory test and clinical assessment groups. These results show that COVID-19-associated chemosensory impairment is not limited to smell, but also affects taste and chemesthesis. The multimodal impact of COVID-19 and lack of perceived nasal obstruction suggest that SARS-CoV-2 infection may disrupt sensory-neural mechanisms.Additional co-authors: Veronica Pereda-Loth, Shannon B Olsson, Richard C Gerkin, Paloma Rohlfs Domínguez, Javier Albayay, Michael C. Farruggia, Surabhi Bhutani, Alexander W Fjaeldstad, Ritesh Kumar, Anna Menini, Moustafa Bensafi, Mari Sandell, Iordanis Konstantinidis, Antonella Di Pizio, Federica Genovese, Lina Öztürk, Thierry Thomas-Danguin, Johannes Frasnelli, Sanne Boesveldt, Özlem Saatci, Luis R. Saraiva, Cailu Lin, Jérôme Golebiowski, Liang-Dar Hwang, Mehmet Hakan Ozdener, Maria Dolors Guàrdia, Christophe Laudamiel, Marina Ritchie, Jan Havlícek, Denis Pierron, Eugeni Roura, Marta Navarro, Alissa A. Nolden, Juyun Lim, KL Whitcroft, Lauren R. Colquitt, Camille Ferdenzi, Evelyn V. Brindha, Aytug Altundag, Alberto Macchi, Alexia Nunez-Parra, Zara M. Patel, Sébastien Fiorucci, Carl M. Philpott, Barry C. Smith, Johan N Lundström, Carla Mucignat, Jane K. Parker, Mirjam van den Brink, Michael Schmuker, Florian Ph.S Fischmeister, Thomas Heinbockel, Vonnie D.C. Shields, Farhoud Faraji, Enrique Enrique Santamaría, William E.A. Fredborg, Gabriella Morini, Jonas K. Olofsson, Maryam Jalessi, Noam Karni, Anna D'Errico, Rafieh Alizadeh, Robert Pellegrino, Pablo Meyer, Caroline Huart, Ben Chen, Graciela M. Soler, Mohammed K. Alwashahi, Olagunju Abdulrahman, Antje Welge-Lüssen, Pamela Dalton, Jessica Freiherr, Carol H. Yan, Jasper H. B. de Groot, Vera V. Voznessenskaya, Hadar Klein, Jingguo Chen, Masako Okamoto, Elizabeth A. Sell, Preet Bano Singh, Julie Walsh-Messinger, Nicholas S. Archer, Sachiko Koyama, Vincent Deary, Hüseyin Yanik, Samet Albayrak, Lenka Martinec Novákov, Ilja Croijmans, Patricia Portillo Mazal, Shima T. Moein, Eitan Margulis, Coralie Mignot, Sajidxa Mariño, Dejan Georgiev, Pavan K. Kaushik, Bettina Malnic, Hong Wang, Shima Seyed-Allaei, Nur Yoluk, Sara Razzaghi, Jeb M. Justice, Diego Restrepo, Julien W Hsieh, Danielle R. Reed, Thomas Hummel, Steven D Munger, John E Haye

Two networks involved in producing and realizing plans

Planning is essential for normal daily activities. Although the dorsolateral prefrontal cortex (DLPFC) is thought to be crucially involved in planning, it remains to be understood whether this contribution is attributable to working memory requirements of the tasks and when it occurs, whether during initial planning or during subsequent plan execution. Here, we compared patterns of activation observed when participants planned and executed their plans to solve Tower of Hanoi problems to when they had to memorize and reproduce externally presented sequences of moves. The DLPFC was preferentially active during initial planning relative to both plan execution and initial memorization of sequences of moves. By contrast, plan execution relied on posterior temporal areas, inferior frontal regions and the dorsolateral premotor cortex. We attribute activation in DLPFC to generation and evaluation of abstract sequences of responses, and activation in the regions underlying plan execution to rehearsal of planned sequences of moves

Processing of Emotional Expressions in Working Memory: Insights from a Modified Span Task

Emotional expressions are vital emotional cues in our lives. However, the precise mechanisms involved in processing these expressions within working memory (WM) remain elusive. To address this, our study employed a modified span task with forward and backward recalls to examine the impact of happy and angry emotional expressions on WM storage and updating. Our task incorporated various memoranda, including faces, shapes, and digits, within a single paradigm, enabling us to examine the influence of emotional expressions when they were either relevant (linked with faces) or non-relevant (linked with shapes or digits) to the task. Additionally, we administered a set of questionnaires to explore the potential influence of individuals' affective symptoms on their WM for emotional expressions. Our findings revealed distinct processing patterns for faces, shapes, and digits in WM, which align with previous research. Interestingly however, we did not find any significant impact of emotional expressions on WM performance. Furthermore, we discovered that WM for emotional expressions operated independently of individuals' affective symptoms, with a notable exception for utilizing reappraisal as an emotion regulation strategy. In sum, our study provides novel insights into the complex interplay between emotion and WM, by shedding light on the mechanisms governing the processing of emotional expressions within this cognitive system

Processing of Emotional Expressions in Working Memory: Insights from a Modified Span Task

Emotional expressions are vital emotional cues in our lives. However, the precise mechanisms involved in processing these expressions within working memory (WM) remain elusive. To address this, our study employed a modified span task with forward and backward recalls to examine the impact of happy and angry emotional expressions on WM storage and updating. Our task incorporated various memoranda, including faces, shapes, and digits, within a single paradigm, enabling us to examine the influence of emotional expressions when they were either relevant (linked with faces) or non-relevant (linked with shapes or digits) to the task. Additionally, we administered a set of questionnaires to explore the potential influence of individuals' affective symptoms on their WM for emotional expressions. Our findings revealed distinct processing patterns for faces, shapes, and digits in WM, which align with previous research. Interestingly however, we did not find any significant impact of emotional expressions on WM performance. Furthermore, we discovered that WM for emotional expressions operated independently of individuals' affective symptoms, with a notable exception for utilizing reappraisal as an emotion regulation strategy. In sum, our study provides novel insights into the complex interplay between emotion and WM, by shedding light on the mechanisms governing the processing of emotional expressions within this cognitive system

Mechanisms of rule acquisition and rule following in inductive reasoning

Despite the recent interest in the neuroanatomy of inductive reasoning processes, the regional specificity within prefrontal cortex (PFC) for the different mechanisms involved in induction tasks remains to be determined. In this study, we used fMRI to investigate the contribution of PFC regions to rule acquisition (rule search and rule discovery) and rule following. Twenty-six healthy young adult participants were presented with a series of images of cards, each consisting of a set of circles numbered in sequence with one colored blue. Participants had to predict the position of the blue circle on the next card. The rules that had to be acquired pertained to the relationship among succeeding stimuli. Responses given by subjects were categorized in a series of phases either tapping rule acquisition (responses given up to and including rule discovery) or rule following (correct responses after rule acquisition). Mid-dorsolateral PFC (mid-DLPFC) was active during rule search and remained active until successful rule acquisition. By contrast, rule following was associated with activation in temporal, motor, and medial/anterior prefrontal cortex. Moreover, frontopolar cortex (FPC) was active throughout the rule acquisition and rule following phases before a rule became familiar. We attributed activation in mid-DLPFC to hypothesis generation and in FPC to integration of multiple separate inferences. The present study provides evidence that brain activation during inductive reasoning involves a complex network of frontal processes and that different subregions respond during rule acquisition and rule following phases

fMRI single trial discovery of spatio-temporal brain activity patterns

There is growing interest in the description of short-lived patterns in the spatiotemporal cortical activity monitored via neuroimaging. Most traditional analysis methods, designed to estimate relatively long-term brain dynamics, are not always appropriate to capture these patterns. Here we introduce a novel data-driven approach for detecting short-lived fMRI brain activity patterns. Exploiting Density Peak Clustering (Rodriguez and Laio [2014]), our approach reveals well localized clusters by identifying and grouping together voxels whose time-series are similar, irrespective of their brain location, even when very short time windows ( 3c10 volumes) are used. The method, which we call Coherence Density Peak Clustering (CDPC), is first tested on simulated data and compared with a standard unsupervised approach for fMRI analysis, independent component analysis (ICA). CDPC identifies activated voxels with essentially no false-positives and proves more reliable than ICA, which is troubled by a number of false positives comparable to that of true positives. The reliability of the method is demonstrated on real fMRI data from a simple motor task, containing brief iterations of the same movement. The clusters identified are found in regions expected to be involved in the task, and repeat synchronously with the paradigm. The methodology proposed is especially suitable for the study of short-time brain dynamics and single trial experiments, where the event or task of interest cannot be repeated for the same subject, as happens, for instance, in problem-solving, learning and decision-making. A GUI implementation of our method is available for download at https://github.com/micheleallegra/CDPC. Hum Brain Mapp 38:1421-1437, 2017. \ua9 2016 Wiley Periodicals, Inc

The Neural basis of free language choice in bilingual speakers: disentangling language choice and language execution

For everyday communication, bilingual speakers need to face the complex task of rapidly choosing the most appropriate language given the context, maintaining this choice over the current communicative act, and shielding lexical selection from competing alternatives from non-target languages. Yet, speech production of bilinguals is typically flawless and fluent. Most of the studies available to date constrain speakers' language choice by cueing the target language and conflate language choice with language use. This left largely unexplored the neural mechanisms underlying free language choice, i.e., the voluntary situation of choosing the language to speak. In this study, we used fMRI and Multivariate Pattern Analysis to identify brain regions encoding the target language when bilinguals are free to choose in which language to name pictures. We found that the medial prefrontal cortex encoded the chosen language prior to speaking. By contrast, during language use, language control recruited a wider brain network including the left inferior frontal lobe, the basal ganglia, and the angular and inferior parietal gyrus bilaterally. None of these regions were involved in language choice. We argue that the control processes involved in language choice are different from those involved in language use. Furthermore, our findings confirm that the medial prefrontal cortex is a domain-general region critical for free choice and that bilingual language choice relies on domain general processes.CR and SSA were supported by the PRIN grant 2010RP5RNM_001 from the Italian Ministry of University; AC was supported by two grants from the Spanish Government, PSI2011-23033, PSI2014-52181-P, a grant from the Catalan government (AGAUR SGR 268), and a grant from the European Research Council under the European Community's Seventh Framework Programme (FP7/2007–2013 Cooperation grant agreement nº 613465 - AThEME)