Browsing by Author "Nummenmaa, Lauri"
Now showing 1 - 20 of 50
- Results Per Page
- Sort Options
- Atlas of type 2 dopamine receptors in the human brain: Age and sex dependent variability in a large PET cohort
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2022-07-15) Malén, Tuulia; Karjalainen, Tomi; Isojärvi, Janne; Vehtari, Aki; Bürkner, Paul Christian; Putkinen, Vesa; Kaasinen, Valtteri; Hietala, Jarmo; Nuutila, Pirjo; Rinne, Juha; Nummenmaa, LauriBackground: The dopamine system contributes to a multitude of functions ranging from reward and motivation to learning and movement control, making it a key component in goal-directed behavior. Altered dopaminergic function is observed in neurological and psychiatric conditions. Numerous factors have been proposed to influence dopamine function, but due to small sample sizes and heterogeneous data analysis methods in previous studies their specific and joint contributions remain unresolved. Methods: In this cross-sectional register-based study we investigated how age, sex, body mass index (BMI), as well as cerebral hemisphere and regional volume influence striatal type 2 dopamine receptor (D2R) availability in the human brain. We analyzed a large historical dataset (n=156, 120 males and 36 females) of [11C]raclopride PET scans performed between 2004 and 2018. Results: Striatal D2R availability decreased through age for both sexes (2-5 % in striatal ROIs per 10 years) and was higher in females versus males throughout age (7-8% in putamen). BMI and striatal D2R availability were weakly associated. There was no consistent lateralization of striatal D2R. The observed effects were independent of regional volumes. These results were validated using two different spatial normalization methods, and the age and sex effects also replicated in an independent sample (n=135). Conclusions: D2R availability is dependent on age and sex, which may contribute to the vulnerability of neurological and psychiatric conditions involving altering D2R expression. - Attending to and neglecting people
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2016-05-05) Hari, Riitta; Sams, Mikko; Nummenmaa, LauriHuman behaviour is context-dependent—based on predictions and influenced by the environment and other people. We live in a dynamic world where both the social stimuli and their context are constantly changing. Similar dynamic, natural stimuli should, in the future, be increasingly used to study social brain functions, with parallel development of appropriate signal-analysis methods. Understanding dynamic neural processes also requires accurate time-sensitive characterization of the behaviour. To go beyond the traditional stimulus–response approaches, brain activity should be recorded simultaneously from two interacting subjects to reveal why human social interaction is critically different from just reacting to each other. This theme issue on Attending to and neglecting people contains original work and review papers on person perception and social interaction. The articles cover research from neuroscience, psychology, robotics, animal interaction research and microsociology. Some of the papers are co-authored by scientists who presented their own, independent views in the recent Attention and Performance XXVI conference but were brave enough to join forces with a colleague having a different background and views. In the future, information needs to converge across disciplines to provide us a more holistic view of human behaviour, its interactive nature, as well as the temporal dynamics of our social world. - Autism spectrum traits predict the neural response to eye gaze in typical individuals
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2012) Nummenmaa, Lauri; Engell, Andrew D.; von dem Hagen, Elisabeth; Henson, Richard N.A; Calder, Andrew J.Autism Spectrum Disorders (ASD) are neurodevelopmental disorders characterised by impaired social interaction and communication, restricted interests and repetitive behaviours. The severity of these characteristics are posited to lie on a continuum extending into the typical population, and typical adults' performance on behavioural tasks that are impaired in ASD is correlated with the extent to which they display autistic traits (as measured by Autism Spectrum Quotient, AQ). Individuals with ASD also show structural and functional differences in brain regions involved in social perception. Here we show that variation in AQ in typically developing individuals is associated with altered brain activity in the neural circuit for social attention perception while viewing others' eye gaze. In an fMRI experiment, participants viewed faces looking at variable or constant directions. In control conditions, only the eye region was presented or the heads were shown with eyes closed but oriented at variable or constant directions. The response to faces with variable vs. constant eye gaze direction was associated with AQ scores in a number of regions (posterior superior temporal sulcus, intraparietal sulcus, temporoparietal junction, amygdala, and MT/V5) of the brain network for social attention perception. No such effect was observed for heads with eyes closed or when only the eyes were presented. The results demonstrate a relationship between neurophysiology and autism spectrum traits in the typical (non-ASD) population and suggest that changes in the functioning of the neural circuit for social attention perception is associated with an extended autism spectrum in the typical population. - Behavioural activation system sensitivity is associated with cerebral μ-opioid receptor availability
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2016-04-06) Karjalainen, Tomi; Tuominen, Lauri; Manninen, Sandra; Kalliokoski, Kari K.; Nuutila, Pirjo; Jääskeläinen, Iiro; Hari, Riitta; Sams, Mikko; Nummenmaa, LauriThe reinforcement-sensitivity theory proposes that behavioural activation and inhibition systems (BAS and BIS, respectively) guide approach and avoidance behaviour in potentially rewarding and punishing situations. Their baseline activity presumably explains individual differences in behavioural dispositions when a person encounters signals of reward and harm. Yet, neurochemical bases of BAS and BIS have remained poorly understood. Here we used in vivo positron emission tomography with a μ-opioid receptor (MOR) specific ligand [11C]carfentanil to test whether individual differences in MOR availability would be associated with BAS or BIS. We scanned 49 healthy subjects and measured their BAS and BIS sensitivities using the BIS/BAS scales. BAS but not BIS sensitivity was positively associated with MOR availability in frontal cortex, amygdala, ventral striatum, brainstem, cingulate cortex and insula. Strongest associations were observed for the BAS subscale ‘Fun Seeking’. Our results suggest that endogenous opioid system underlies BAS, and that differences in MOR availability could explain inter-individual differences in reward seeking behaviour. - Bodily feelings and aesthetic experience of art
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2023) Nummenmaa, Lauri; Hari, RiittaHumans all around the world are drawn to creating and consuming art due to its capability to evoke emotions, but the mechanisms underlying art-evoked feelings remain poorly characterised. Here we show how embodiement contributes to emotions evoked by a large database of visual art pieces (n = 336). In four experiments, we mapped the subjective feeling space of art-evoked emotions (n = 244), quantified “bodily fingerprints” of these emotions (n = 615), and recorded the subjects’ interest annotations (n = 306) and eye movements (n = 21) while viewing the art. We show that art evokes a wide spectrum of feelings, and that the bodily fingerprints triggered by art are central to these feelings, especially in artworks where human figures are salient. Altogether these results support the model that bodily sensations are central to the aesthetic experience. - Bodily maps of emotions are culturally universal
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2020-10) Volynets, Sofia; Glerean, Enrico; Hietanen, Jari K; Hari, Riitta; Nummenmaa, LauriEmotions are often felt in the body, and interoceptive feedback is an important component of conscious emotional experiences. Here, we provide support for the cultural universality of bodily sensations associated with 13 emotions in a large international sample (3,954 individuals from 101 countries; age range = 18-90). Participants were presented with 2 silhouettes of bodies alongside emotional words and asked to color the bodily regions whose activity they felt increasing or decreasing while they experienced each given emotion. We tested the effects of various background factors (i.e., age, sex, education, body mass index, nationality, civilization, and language) on the bodily sensation maps. Bodily sensations associated with emotions were concordant across the tested cultures (rs > 0.82) and across the sexes (r > 0.80). Bodily sensations weakened during aging (M rs = 0.11 across emotions). We conclude that universality in experiencing emotions in the body is stronger than the differences due to culture or sex. - Bodily maps of musical sensations across cultures
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2024-01-25) Putkinen, Vesa; Zhou, Xinqi; Gan, Xianyang; Yang, Linyu; Becker, Benjamin; Sams, Mikko; Nummenmaa, LauriEmotions, bodily sensations and movement are integral parts of musical experiences. Yet, it remains unknown i) whether emotional connotations and structural features of music elicit discrete bodily sensations and ii) whether these sensations are culturally consistent. We addressed these questions in a cross-cultural study with Western (European and North American, n = 903) and East Asian (Chinese, n = 1035). We precented participants with silhouettes of human bodies and asked them to indicate the bodily regions whose activity they felt changing while listening to Western and Asian musical pieces with varying emotional and acoustic qualities. The resulting bodily sensation maps (BSMs) varied as a function of the emotional qualities of the songs, particularly in the limb, chest, and head regions. Music-induced emotions and corresponding BSMs were replicable across Western and East Asian subjects. The BSMs clustered similarly across cultures, and cluster structures were similar for BSMs and self-reports of emotional experience. The acoustic and structural features of music were consistently associated with the emotion ratings and music-induced bodily sensations across cultures. These results highlight the importance of subjective bodily experience in music-induced emotions and demonstrate consistent associations between musical features, music-induced emotions, and bodily sensations across distant cultures. - Bodily Maps of Symptoms and Emotions in Parkinson's Disease
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2024-06) Niemi, Kalle J.; Huovinen, Annu; Jaakkola, Elina; Glerean, Enrico; Nummenmaa, Lauri; Joutsa, JuhoBackground: Emotions are reflected in bodily sensations, and these reflections are abnormal in psychiatric conditions. However, emotion-related bodily sensations have not been studied in neurological disorders. Objective: The aim of this study was to investigate whether Parkinson's disease (PD) is associated with altered bodily representations of emotions. Methods: Symptoms and emotion-related sensations were investigated in 380 patients with PD and 79 control subjects, using a topographical self-report method, termed body sensation mapping. The bodily mapping data were analyzed with pixelwise generalized linear models and principal component analyses. Results: Bodily maps of symptoms showed characteristic patterns of PD motor symptom distributions. Compared with control subjects, PD patients showed decreased parasternal sensation of anger, and longer PD symptom duration was associated with increased abdominal sensation of anger (PFWE < 0.05). The PD-related sensation patterns were abnormal across all basic emotions (P < 0.05). Conclusions: The results demonstrate altered bodily maps of emotions in PD, providing novel insight into the nonmotor effects of PD. - Brain Basis of Complex Emotions: An fMRI Study
Perustieteiden korkeakoulu | Master's thesis(2014-08-19) Ejtehadian, FarzanehIn the past, several studies have been conducted in order to examine the psychological and neural bases of emotions. These studies have mostly concentrated on a narrow range of often negative basic emotions, thus neglecting psychologically complex emotions. Only in recent years neuroimaging studies have begun to describe the neuroanatomy of more complex emotions. In this study, functional magnetic resonance imaging (fMRI) is used to investigate the brain activation for basic and complex emotions in 25 healthy participants. 15 different emotions are induced using a series of short emotional stories. The brain activation is analysed by categorical and parametric designs, as well as using the behavioural ratings of dimensions of complex emotion stimuli. The objective is to examine if specific brain regions are associated with activation in different emotions, and whether these regions are common for multiple emotions. In addition, the difference in activation for basic and complex emotions is discussed. Furthermore, the brain activation pattern underlying the dimensions of valence and arousal is investigated. The findings point to the involvement of a network of structures in the midbrain regions and the somatosensory and motor cortices for a group of emotions. Also, several brain areas, including the middle and inferior occipital cortex, cerebellum, precuneus and cuneus, are found to underlie the dimensions of negative valence and positive arousal. - Brain mechanisms of sensory and vicarious pain
Sähkötekniikan korkeakoulu | Master's thesis(2015-02-09) Karjalainen, TomiThe aim of the Thesis was to study the brain circuits representing sensory and vicarious pain. Experiments with functional magnetic resonance imaging were conducted to study neural activity patterns evoked by both stimulus modalities. Sensory pain was induced to subjects by applying noxious heat to right foot, while pictures of painful feet were used to arouse vicarious pain. Sensory pain was modeled in three different ways within the framework of the general linear model: The event-like model assumes that brain’s pain-circuits are activated only during noxious stimulus, while the two other models that used long and intermediate blocks additionally assume, to different degrees, that also expectation of pain activates the same circuits. Both sensory and vicarious pain triggered robust neural activity increase in partly overlapping but mostly neighboring clusters in an area extending bilaterally from midcingulate cortex to supplementary motor area. The self-related pain cluster located slightly posterior to the other- related cluster. Stimulus-modality-specific brain regions exhibiting increased activation included somatosensory cortex and bilateral anterior insula for sensory pain and occipital cortex for vicarious pain. Among the tested models of pain perception, the event-like model yielded results that most closely match previously reported findings. Overall, the results of the Thesis accord with prior literature, and thus confirm the suitability of the selected stimuli and experimental design for studying brain circuits representing pain. Help- promotion is suggested to account for the partly shared neural representations of sensory and vicarious pain. The results and the model’s straightforward interpretability strongly support the use of the event-like model in future studies investigating brain activity reflecting sensory pain. - Brain structural alterations in autism and criminal psychopathy
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2022) Noppari, Tuomo; Sun, Lihua; Lukkarinen, Lasse; Putkinen, Vesa; Tani, Pekka; Lindberg, Nina; Saure, Emma; Lauerma, Hannu; Tiihonen, Jari; Venetjoki, Niina; Salomaa, Marja; Rautio, Päivi; Hirvonen, Jussi; Salmi, Juha; Nummenmaa, LauriThe goal of this study was to elucidate the anatomical brain basis of social cognition through two disorders with distinctively different phenotypes of social interaction. We compared structural MR images of 20 individuals with autism spectrum disorder (ASD), 19 violent offenders with high psychopathic traits, and 19 control participants using voxel-based morphometry (VBM). Our earlier study showed lower grey matter volume (GMV) values in the insula, frontal cortex, and sensorimotor cortex of the offender group compared to controls. In the present study, the images of the ASD group revealed lower GMV in the left precuneus, right cerebellum, and right precentral gyrus in comparison with controls. The comparison between the offender and ASD groups showed lower GMV values for the right temporal pole and left inferior frontal gyrus in the offender group. There was also an overlap of both disorders in the right pre-central cortex, showing lower GMV compared to controls. Our findings suggest structural differences between violent offenders with high psychopathy traits and ASD individuals in the frontotemporal social brain network areas, previously associated with empathy. We also provide evidence of similar abnormal structures in the motor cortex for both of these disorders, possibly related to uniting issues of social cognition. - Brain-to-brain hyperclassification reveals action-specific motor mapping of observed actions in humans
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2017-12-11) Smirnov, Dmitry; Lachat, Fanny; Peltola, Tomi; Lahnakoski, Juha; Koistinen, Olli-Pekka; Glerean, Enrico; Vehtari, Aki; Hari, Riitta; Sams, Mikko; Nummenmaa, LauriSeeing an action may activate the corresponding action motor code in the observer. It remains unresolved whether seeing and performing an action activates similar action-specific motor codes in the observer and the actor. We used novel hyperclassification approach to reveal shared brain activation signatures of action execution and observation in interacting human subjects. In the first experiment, two "actors" performed four types of hand actions while their haemodynamic brain activations were measured with 3-T functional magnetic resonance imaging (fMRI). The actions were videotaped and shown to 15 "observers" during a second fMRI experiment. Eleven observers saw the videos of one actor, and the remaining four observers saw the videos of the other actor. In a control fMRI experiment, one of the actors performed actions with closed eyes, and five new observers viewed these actions. Bayesian canonical correlation analysis was applied to functionally realign observers' and actors' fMRI data. Hyperclassification of the seen actions was performed with Bayesian logistic regression trained on actors' data and tested with observers' data. Without the functional realignment, between-subjects accuracy was at chance level. With the realignment, the accuracy increased on average by 15 percentage points, exceeding both the chance level and the accuracy without functional realignment. The highest accuracies were observed in occipital, parietal and premotor cortices. Hyperclassification exceeded chance level also when the actor did not see her own actions. We conclude that the functional brain activation signatures underlying action execution and observation are partly shared, yet these activation signatures may be anatomically misaligned across individuals. - The brains of high functioning autistic individuals do not synchronize with those of others
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2013) Salmi, Juha; Roine, Ulrika; Glerean, Enrico; Lahnakoski, Juha; Nieminen-von Wendt, Taina; Tani, P; Leppämäki, S; Nummenmaa, Lauri; Jääskeläinen, Iiro P.; Carlson, Synnöve; Rintahaka, P; Sams, MikkoMultifaceted and idiosyncratic aberrancies in social cognition characterize autism spectrum disorders (ASDs). To advance understanding of underlying neural mechanisms, we measured brain hemodynamic activity with functional magnetic resonance imaging (fMRI) in individuals with ASD and matched-pair neurotypical (NT) controls while they were viewing a feature film portraying social interactions. Pearson's correlation coefficient was used as a measure of voxelwise similarity of brain activity (InterSubject Correlations—ISCs). Individuals with ASD showed lower ISC than NT controls in brain regions implicated in processing social information including the insula, posterior and anterior cingulate cortex, caudate nucleus, precuneus, lateral occipital cortex, and supramarginal gyrus. Curiously, also within NT group, autism-quotient scores predicted ISC in overlapping areas, including, e.g., supramarginal gyrus and precuneus. In ASD participants, functional connectivity was decreased between the frontal pole and the superior frontal gyrus, angular gyrus, superior parietal lobule, precentral gyrus, precuneus, and anterior/posterior cingulate gyrus. Taken together these results suggest that ISC and functional connectivity measure distinct features of atypical brain function in high-functioning autistic individuals during free viewing of acted social interactions. Our ISC results suggest that the minds of ASD individuals do not ‘tick together’ with others while perceiving identical dynamic social interactions. - Classification of emotion categories based on functional connectivity patterns of the human brain
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2022-02-15) Saarimäki, Heini; Glerean, Enrico; Smirnov, Dmitry; Mynttinen, Henri; Jääskeläinen, Iiro P.; Sams, Mikko; Nummenmaa, LauriNeurophysiological and psychological models posit that emotions depend on connections across wide-spread corticolimbic circuits. While previous studies using pattern recognition on neuroimaging data have shown differences between various discrete emotions in brain activity patterns, less is known about the differences in functional connectivity. Thus, we employed multivariate pattern analysis on functional magnetic resonance imaging data (i) to develop a pipeline for applying pattern recognition in functional connectivity data, and (ii) to test whether connectivity patterns differ across emotion categories. Six emotions (anger, fear, disgust, happiness, sadness, and surprise) and a neutral state were induced in 16 participants using one-minute-long emotional narratives with natural prosody while brain activity was measured with functional magnetic resonance imaging (fMRI). We computed emotion-wise connectivity matrices both for whole-brain connections and for 10 previously defined functionally connected brain subnetworks and trained an across-participant classifier to categorize the emotional states based on whole-brain data and for each subnetwork separately. The whole-brain classifier performed above chance level with all emotions except sadness, suggesting that different emotions are characterized by differences in large-scale connectivity patterns. When focusing on the connectivity within the 10 subnetworks, classification was successful within the default mode system and for all emotions. We thus show preliminary evidence for consistently different sustained functional connectivity patterns for instances of emotion categories particularly within the default mode system. - Classification of emotions from functional connectivity graphs
Sähkötekniikan korkeakoulu | Master's thesis(2016-10-31) Mynttinen, HenriFunctional neuroimaging has proven to be a valuable tool in mapping local brain activation patterns corresponding to different perceptual and behavioral tasks. In functional magnetic resonance imaging the task-related changes in blood oxygenation level are inspected and inference about the involvement of brain locations is made based on statistical modelling and testing. The statistical models have traditionally been univariate allowing for inference on individual parts of the brain (voxels) and requiring correction for multiple comparisons. Recent applications of machine learning in neuroscience extended the univariate approach to multivariate methods that consider the simultaneous involvement of multiple voxels in modelling the brain activation. Particularly, classification algorithms have enabled brain state decoding in which the current task is predicted from the local activation pattern. However, the generalizability of the method in studies concerning emotional states has been poor due to the distributed nature of emotional information. In this thesis, connectivity patterns were used to discriminate between different emotional states. Based on functional connectivity between pairs of brain areas (nodes), the classifier was able to determine the corresponding emotional state by an accuracy significantly above the chance level. The classification was performed using three different sets of nodes and it was demonstrated that the choice of nodes does impact the classification accuracy. The results show that similarities exist among the connectivity patterns of multiple individuals and that discrimination between brain states is possible based on these patterns. The results also demonstrate that machine learning applications are powerful enough to extract underlying connectivity structure from the data even with moderately few samples. Further studies are required to investigate if increasing the sample size allows using more detailed node structures. - Cortical Circuit for Binding Object Identity and Location During Multiple-Object Tracking
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2016-12-01) Nummenmaa, Lauri; Oksama, Lauri; Glerean, Enrico; Hyönä, JukkaSustained multifocal attention for moving targets requires binding object identities with their locations. The brain mechanisms of identity-location binding during attentive tracking have remained unresolved. In 2 functional magnetic resonance imaging experiments, we measured participants’ hemodynamic activity during attentive tracking of multiple objects with equivalent (multiple-object tracking) versus distinct (multiple identity tracking, MIT) identities. Task load was manipulated parametrically. Both tasks activated large frontoparietal circuits. MIT led to significantly increased activity in frontoparietal and temporal systems subserving object recognition and working memory. These effects were replicated when eye movements were prohibited. MIT was associated with significantly increased functional connectivity between lateral temporal and frontal and parietal regions. We propose that coordinated activity of this network subserves identity-location binding during attentive tracking. - Cross-cultural similarity in relationship-specific social touching
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2019-04-17) Suvilehto, Juulia T.; Nummenmaa, Lauri; Harada, Tokiko; Dunbar, Robin IM; Hari, Riitta; Turner, Robin; Sadato, Norihiro; Kitada, RyoMany species use touching for reinforcing social structures, and particularly, non-human primates use social grooming for managing their social networks. However, it is still unclear how social touch contributes to the maintenance and reinforcement of human social networks. Human studies in Western cultures suggest that the body locations where touch is allowed are associated with the strength of the emotional bond between the person touched and the toucher. However, it is unknown to what extent this relationship is culturally universal and generalizes to non-Western cultures. Here, we compared relationship-specific, bodily touch allowance maps across one Western (N = 386, UK) and one East Asian (N = 255, Japan) country. In both cultures, the strength of the emotional bond was linearly associated with permissible touch area. However, Western participants experienced social touching as more pleasurable than Asian participants. These results indicate a similarity of emotional bonding via social touch between East Asian and Western cultures. - Decoding brain basis of laughter and crying in natural scenes
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2023-06) Nummenmaa, Lauri; Malèn, Tuulia; Nazari-Farsani, Sanaz; Seppälä, Kerttu; Sun, Lihua; Santavirta, Severi; Karlsson, Henry K.; Hudson, Matthew; Hirvonen, Jussi; Sams, Mikko; Scott, Sophie; Putkinen, VesaLaughter and crying are universal signals of prosociality and distress, respectively. Here we investigated the functional brain basis of perceiving laughter and crying using naturalistic functional magnetic resonance imaging (fMRI) approach. We measured haemodynamic brain activity evoked by laughter and crying in three experiments with 100 subjects in each. The subjects i) viewed a 20-minute medley of short video clips, and ii) 30 min of a full-length feature film, and iii) listened to 13.5 min of a radio play that all contained bursts of laughter and crying. Intensity of laughing and crying in the videos and radio play was annotated by independent observes, and the resulting time series were used to predict hemodynamic activity to laughter and crying episodes. Multivariate pattern analysis (MVPA) was used to test for regional selectivity in laughter and crying evoked activations. Laughter induced widespread activity in ventral visual cortex and superior and middle temporal and motor cortices. Crying activated thalamus, cingulate cortex along the anterior-posterior axis, insula and orbitofrontal cortex. Both laughter and crying could be decoded accurately (66–77% depending on the experiment) from the BOLD signal, and the voxels contributing most significantly to classification were in superior temporal cortex. These results suggest that perceiving laughter and crying engage distinct neural networks, whose activity suppresses each other to manage appropriate behavioral responses to others’ bonding and distress signals. - Developing game for brain research
Sähkötekniikan korkeakoulu | Master's thesis(2015-03-30) Simonen, Taru - Dissociable neural systems for unconditioned acute and sustained fear
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2020-08-01) Hudson, Matthew; Seppälä, Kerttu; Putkinen, Vesa; Sun, Lihua; Glerean, Enrico; Karjalainen, Tomi; Karlsson, Henry K.; Hirvonen, Jussi; Nummenmaa, LauriFear protects organisms by increasing vigilance and preparedness, and by coordinating survival responses during life-threatening encounters. The fear circuit must thus operate on multiple timescales ranging from preparatory sustained alertness to acute fight-or-flight responses. Here we studied the brain basis of sustained and acute fear using naturalistic functional magnetic resonance imaging (fMRI) enabling analysis of different time-scales of fear responses. Subjects (N = 37) watched feature-length horror movies while their hemodynamic brain activity was measured with fMRI. Time-variable intersubject correlation (ISC) was used to quantify the reliability of brain activity across participants, and seed-based phase synchronization was used for characterizing dynamic connectivity. Subjective ratings of fear were used to assess how synchronization and functional connectivity varied with emotional intensity. These data suggest that acute and sustained fear are supported by distinct neural pathways, with sustained fear amplifying mainly sensory responses, and acute fear increasing activity in brainstem, thalamus, amygdala and cingulate cortices. Sustained fear increased ISC in regions associated with acute fear, and also amplified functional connectivity within this network. The results were replicated in an independent experiment with a different subject sample and stimulus movie. The functional interplay between cortical networks involved in sustained anticipation of, and acute response to, threat involves a complex and dynamic interaction that depends on the proximity of threat, and the need to employ threat appraisals and vigilance for decision making and response selection.
- «
- 1 (current)
- 2
- 3
- »