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  • 101.
    Åhs, Fredrik
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Startle potentiation is modulated by the medial temporal lobes in aversive anticipation but not in aversive sensitization2007Inngår i: Biol. Psychiatry 61, 28S-28S, 2007Konferansepaper (Fagfellevurdert)
  • 102.
    Åhs, Fredrik
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Bjurström, A
    Fredriksson, Mats
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Furmark, Tomas
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Pissiota, A
    Linnman, Clas
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Michelgård, A
    Appel, L
    Bani, M
    Merlo Pich, E
    Zancan, S
    Långström, B
    Gustavsson, M
    Connectivity analyses of regional cerebral blood flow during public speaking in individuals with social anxiety disorder2005Konferansepaper (Annet (populærvitenskap, debatt, mm))
  • 103.
    Åhs, Fredrik
    et al.
    Duke University, Durham, USA.
    Davis, Caroline F
    Duke University, Durham, USA.
    Gorka, Adam X
    Duke University, Durham, USA.
    Hariri, Ahmad R
    Duke University, Durham, USA.
    Feature-based representations of emotional facial expressions in the human amygdala.2014Inngår i: Social Cognitive & Affective Neuroscience, ISSN 1749-5016, E-ISSN 1749-5024, Vol. 9, nr 9, s. 1372-1378Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The amygdala plays a central role in processing facial affect, responding to diverse expressions and features shared between expressions. Although speculation exists regarding the nature of relationships between expression- and feature-specific amygdala reactivity, this matter has not been fully explored. We used functional magnetic resonance imaging and principal component analysis (PCA) in a sample of 300 young adults, to investigate patterns related to expression- and feature-specific amygdala reactivity to faces displaying neutral, fearful, angry or surprised expressions. The PCA revealed a two-dimensional correlation structure that distinguished emotional categories. The first principal component separated neutral and surprised from fearful and angry expressions, whereas the second principal component separated neutral and angry from fearful and surprised expressions. This two-dimensional correlation structure of amygdala reactivity may represent specific feature-based cues conserved across discrete expressions. To delineate which feature-based cues characterized this pattern, face stimuli were averaged and then subtracted according to their principal component loadings. The first principal component corresponded to displacement of the eyebrows, whereas the second principal component corresponded to increased exposure of eye whites together with movement of the brow. Our results suggest a convergent representation of facial affect in the amygdala reflecting feature-based processing of discrete expressions.

    Fulltekst (pdf)
    fulltext
  • 104.
    Åhs, Fredrik
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Dunsmoor, Joseph E.
    Zielinski, David
    LaBar, Kevin S.
    Spatial proximity amplifies valence in emotional memory and defensive approach-avoidance2015Inngår i: Neuropsychologia, ISSN 0028-3932, E-ISSN 1873-3514, Vol. 70, s. 476-485Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In urban areas, people often have to stand or move in close proximity to others. The egocentric distance to stimuli is a powerful determinant of defensive behavior in animals. Yet, little is known about how spatial proximity to others alters defensive responses in humans. We hypothesized that the valence of social cues scales with egocentric distance, such that proximal social stimuli have more positive or negative valence than distal stimuli. This would predict enhanced defensive responses to proximal threat and reduced defensive responses to proximal reward. We tested this hypothesis across four experiments using 3-D virtual reality simulations. Results from Experiment 1 confirmed that proximal social stimuli facilitate defensive responses, as indexed by fear-potentiated startle, relative to distal stimuli. Experiment 2 revealed that interpersonal defensive boundaries flexibly increase with aversive learning. Experiment 3 examined whether spatial proximity enhances memory for aversive experiences. Fear memories for social threats encroaching on the body were more persistent than those acquired at greater interpersonal distances, as indexed by startle. Lastly, Experiment 4 examined how egocentric distance influenced startle responses to social threats during defensive approach and avoidance. Whereas fear-potentiated startle increased with proximity when participants actively avoided receiving shocks, startle decreased with proximity when participants tolerated shocks to receive monetary rewards, implicating opposing gradients of distance on threat versus reward. Thus, proximity in egocentric space amplifies the valence of social stimuli that, in turn, facilitates emotional memory and approach-avoidance responses. These findings have implications for understanding the consequences of increased urbanization on affective interpersonal behavior.

  • 105.
    Åhs, Fredrik
    et al.
    Center for Cognitive Neuroscience, Department of Psychology and Neuroscience, Duke University, USA; Department of Psychology, Uppsala University, Uppsala, Sweden.
    Dunsmoor, Joseph E
    Center for Cognitive Neuroscience, Department of Psychology and Neuroscience, Duke University, USA; Department of Psychology, New York University, New York, USA.
    Zielinski, David
    Pratt School of Engineering, Duke University, Durham, USA.
    LaBar, Kevin S
    Center for Cognitive Neuroscience, Department of Psychology and Neuroscience, Duke University, USA.
    Spatial proximity amplifies valence in emotional memory and defensive approach-avoidance2015Inngår i: Neuropsychologia, ISSN 0028-3932, E-ISSN 1873-3514, Vol. 70, s. 476-85, artikkel-id S0028-3932(14)00478-3Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In urban areas, people often have to stand or move in close proximity to others. The egocentric distance to stimuli is a powerful determinant of defensive behavior in animals. Yet, little is known about how spatial proximity to others alters defensive responses in humans. We hypothesized that the valence of social cues scales with egocentric distance, such that proximal social stimuli have more positive or negative valence than distal stimuli. This would predict enhanced defensive responses to proximal threat and reduced defensive responses to proximal reward. We tested this hypothesis across four experiments using 3-D virtual reality simulations. Results from Experiment 1 confirmed that proximal social stimuli facilitate defensive responses, as indexed by fear-potentiated startle, relative to distal stimuli. Experiment 2 revealed that interpersonal defensive boundaries flexibly increase with aversive learning. Experiment 3 examined whether spatial proximity enhances memory for aversive experiences. Fear memories for social threats encroaching on the body were more persistent than those acquired at greater interpersonal distances, as indexed by startle. Lastly, Experiment 4 examined how egocentric distance influenced startle responses to social threats during defensive approach and avoidance. Whereas fear-potentiated startle increased with proximity when participants actively avoided receiving shocks, startle decreased with proximity when participants tolerated shocks to receive monetary rewards, implicating opposing gradients of distance on threat versus reward. Thus, proximity in egocentric space amplifies the valence of social stimuli that, in turn, facilitates emotional memory and approach-avoidance responses. These findings have implications for understanding the consequences of increased urbanization on affective interpersonal behavior.

  • 106.
    Åhs, Fredrik
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Engman, Jonas
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Persson, Jonas
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Larsson, Elna-Marie
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för radiologi.
    Wikström, Johan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för radiologi.
    Kumlien, Eva
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Neurologi.
    Fredrikson, Mats
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Medial temporal lobe resection attenuates superior temporal sulcus response to faces2014Inngår i: Neuropsychologia, ISSN 0028-3932, E-ISSN 1873-3514, Vol. 61, s. 291-298Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Face perception depends on activation of a core face processing network including the fusiform face area, the occipital face area and the superior temporal sulcus (STS). The medial temporal lobe (MTL) is also involved in decoding facial expression and damage to the anterior MTL, including the amygdala, generally interferes with emotion recognition. The impairment in emotion recognition following anterior MTL injury can be a direct result from injured MTL circuitry, as well as an indirect result from decreased MTL modulation of areas in the core face network. To test whether the MTL modulates activity in the core face network, we used functional magnetic resonance imaging to investigate activation in the core face processing network in patients with right or left anterior temporal lobe resections (ATR) due to intractable epilepsy. We found reductions of face-related activation in the right STS after both right and left ATR together with impaired recognition of facial expressions. Reduced activity in the fusiform and the occipital face areas was also observed in patients after right ATR suggesting widespread effects on activity in the core face network in this group. The reduction in face-related STS activity after both right and left ATR suggests that MTL modulation of the STS may facilitate recognition of facial expression.

  • 107.
    Åhs, Fredrik
    et al.
    Uppsala Universitet.
    Engman, Jonas
    Uppsala Universitet.
    Persson, Jonas
    Uppsala Universitet.
    Larsson, Elna-Marie
    Uppsala Universitet.
    Wikström, Johan
    Uppsala Universitet.
    Kumlien, Eva
    Uppsala Universitet.
    Fredrikson, Mats
    Uppsala Universitet.
    Medial temporal lobe resection attenuates superior temporal sulcus response to faces2014Inngår i: Neuropsychologia, ISSN 0028-3932, E-ISSN 1873-3514, Vol. 61, s. 291-298Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Face perception depends on activation of a core face processing network including the fusiform face area, the occipital face area and the superior temporal sulcus (STS). The medial temporal lobe (MTL) is also involved in decoding facial expression and damage to the anterior MTL, including the amygdala, generally interferes with emotion recognition. The impairment in emotion recognition following anterior MTL injury can be a direct result from injured MTL circuitry, as well as an indirect result from decreased MTL modulation of areas in the core face network. To test whether the MTL modulates activity in the core face network, we used functional magnetic resonance imaging to investigate activation in the core face processing network in patients with right or left anterior temporal lobe resections (ATR) due to intractable epilepsy. We found reductions of face-related activation in the right STS after both right and left ATR together with impaired recognition of facial expressions. Reduced activity in the fusiform and the occipital face areas was also observed in patients after right ATR suggesting widespread effects on activity in the core face network in this group. The reduction in face-related STS activity after both right and left ATR suggests that MTL modulation of the STS may facilitate recognition of facial expression.

  • 108.
    Åhs, Fredrik
    et al.
    Uppsala Universitet.
    Frans, Örjan
    Uppsala Universitet.
    Tibblin, Bodil
    Uppsala University Hospital.
    Kumlien, Eva
    Uppsala University Hospital.
    Fredrikson, Mats
    Uppsala Universitet.
    The effects of medial temporal lobe resections on verbal threat and fear conditioning2010Inngår i: Biological Psychology, ISSN 0301-0511, E-ISSN 1873-6246, Vol. 83, nr 1, s. 41-46Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A left hemisphere advantage in the processing of verbal threat has previously been reported, whereas both hemispheres seem equally important in fear conditioning. Here, we compared the effects of unilateral medial temporal lobe (MTL) resections on verbal threat as well as delay and trace fear conditioning. During verbal threat, right and left MTL-resections attenuated fear potentiated startle in comparison with controls. In contrast to previous studies, MTL-resections did not attenuate delay conditioning of skin conductance responses. Left and right resectioned patients did not differ in psychophysiological responses to verbal threat or delay fear conditioning. Trace conditioning was not observed in any group. Results suggest a bilateral MTL hemispheric involvement in the processing of verbal threat, whereas one intact hemisphere seems sufficient for delay conditioning.

  • 109.
    Åhs, Fredrik
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Frick, Andreas
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Furmark, Tomas
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Fredrikson, Mats
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Human serotonin transporter availability predicts fear conditioning2015Inngår i: International Journal of Psychophysiology, ISSN 0167-8760, E-ISSN 1872-7697, Vol. 98, nr 3, s. 515-519Artikkel i tidsskrift (Fagfellevurdert)
  • 110.
    Åhs, Fredrik
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Furmark, Tomas
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Michelgård, Åsa
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Långström, B.
    Appel, L.
    Wolff, O. T.
    Kirschbaum, C.
    Fredriksson, Mats
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Hypothalamic blood flow correlates positively with stress-induced cortisol levels in subjects with social anxiety disorder2006Inngår i: Psychosomatic Medicine, ISSN 0033-3174, E-ISSN 1534-7796, Vol. 68, nr 6, s. 859-862Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Objective: The adrenal excretion of cortisol in animals is dependent on the production of corticotropin-releasing factor in the paraventricular nucleus of the hypothalamus. The a priori hypothesis of this study was that hypothalamic regional cerebral blood flow (rCBF) would correlate positively with salivary cortisol levels in patients with social anxiety disorder (SAD) during anxiety provocation. Another objective was to evaluate whether salivary cortisol levels correlated with rCBF in other brain areas. Method: Regional CBF was measured with oxygen-15-labeled water and positron emission tomography during a public speaking task before and after placebo treatment in 12 subjects with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-defined SAD. Cortisol concentrations in saliva were measured 15 minutes after the task. The a priori hypothesis of a salivary cortisol-dependent activation of the hypothalamus was studied with region-of-interest analysis. In addition, the covariation between rCBF and salivary cortisol was studied in the whole brain using the general linear model. Results: The region-of-interest analysis revealed a positive correlation between salivary cortisol and hypothalamic rCBF. In the whole brain analysis, a positive covariation between rCBF and salivary cortisol levels was found in a midbrain cluster encompassing the hypothalamus with its statistical maximum in the mamillary bodies. Negative covariations were observed in the medial prefrontal cortex as well as in the motor and premotor cortices. Conclusion: Like in animals, stress-induced cortisol excretion in humans may be inhibited by activity in the medial prefrontal cortex and enhanced by activity in the hypothalamus.

  • 111.
    Åhs, Fredrik
    et al.
    Departments of Psychology, Uppsala university, Uppsala, Sweden.
    Furmark, Tomas
    Departments of Psychology, Uppsala university, Uppsala, Sweden.
    Michelgård, Åsa
    Neuroscience, Uppsala university, Uppsala, Sweden.
    Långström, Bengt
    Uppsala Imanet AB, Uppsala, Sweden.
    Appel, Lieuwe
    Uppsala Imanet AB, Uppsala, Sweden.
    Wolf, Oliver T
    Department of Psychology, University of Bielefeld, Bielefeld, Germany.
    Kirschbaum, Clemens
    Biopsychology, Technical University of Dresden, Dresden, Germany..
    Fredrikson, Mats
    Departments of Psychology, Uppsala university, Uppsala, Sweden.
    Hypothalamic blood flow correlates positively with stress-induced cortisol levels in subjects with social anxiety disorder2006Inngår i: Psychosomatic Medicine, ISSN 0033-3174, E-ISSN 1534-7796, Vol. 68, nr 6, s. 859-62Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    OBJECTIVE: The adrenal excretion of cortisol in animals is dependent on the production of corticotropin-releasing factor in the paraventricular nucleus of the hypothalamus. The a priori hypothesis of this study was that hypothalamic regional cerebral blood flow (rCBF) would correlate positively with salivary cortisol levels in patients with social anxiety disorder (SAD) during anxiety provocation. Another objective was to evaluate whether salivary cortisol levels correlated with rCBF in other brain areas.

    METHOD: Regional CBF was measured with oxygen-15-labeled water and positron emission tomography during a public speaking task before and after placebo treatment in 12 subjects with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-defined SAD. Cortisol concentrations in saliva were measured 15 minutes after the task. The a priori hypothesis of a salivary cortisol-dependent activation of the hypothalamus was studied with region-of-interest analysis. In addition, the covariation between rCBF and salivary cortisol was studied in the whole brain using the general linear model.

    RESULTS: The region-of-interest analysis revealed a positive correlation between salivary cortisol and hypothalamic rCBF. In the whole brain analysis, a positive covariation between rCBF and salivary cortisol levels was found in a midbrain cluster encompassing the hypothalamus with its statistical maximum in the mamillary bodies. Negative covariations were observed in the medial prefrontal cortex as well as in the motor and premotor cortices.

    CONCLUSION: Like in animals, stress-induced cortisol excretion in humans may be inhibited by activity in the medial prefrontal cortex and enhanced by activity in the hypothalamus.

  • 112.
    Åhs, Fredrik
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi. Karolinska Inst, Dept Clin Neurosci, Stockholm, Sweden..
    Gingnell, Malin
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kvinnors och barns hälsa, Obstetrik & gynekologi.
    Furmark, Tomas
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Fredrikson, Mats
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi. Karolinska Inst, Dept Clin Neurosci, Stockholm, Sweden..
    Within-session effect of repeated stress exposure on extinction circuitry function in social anxiety disorder2017Inngår i: Psychiatry Research: Neuroimaging, ISSN 0925-4927, E-ISSN 1872-7506, Vol. 261, s. 85-90Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Anxiety reduction following repeated exposure to stressful experiences is generally held to depend on neural processes involved in extinction of conditioned fear. We predicted that repeated exposure to stressful experiences would change activity throughout the circuitry serving extinction, including ventromedial prefrontal cortex (vmPFC), the hippocampus and the amygdala. To test this prediction, 36 participants diagnosed with SAD performed two successive speeches in front of an observing audience while regional cerebral blood flow (rCBF) was recorded using positron emission tomography. To control for non-anxiolytic effects of repeated exposure, rCBF was also measured during repeated presentations of neutral and angry facial expressions. Results showed that anxiety ratings and heart rate decreased from the first to the second speech, indicating an anxiolytic effect of repeated exposure. Exposure attenuated rCBF in the amygdala whereas no change in rCBF was observed in the vmPFC or hippocampus. The rCBF-reductions in the amygdala were greater following repetition of the speech task than repetition of face exposure indicating that they were specific to anxiety attenuation and not due to a reduced novelty. Our findings suggest that amygdala-related attenuation processes are key to understanding the working mechanisms of exposure therapy.

    Fulltekst (pdf)
    fulltext
  • 113.
    Åhs, Fredrik
    et al.
    Uppsala Universitet; Karolinska Institutet.
    Gingnell, Malin
    Uppsala Universitet.
    Furmark, Tomas
    Uppsala Universitet.
    Fredrikson, Mats
    Uppsala Universitet; Karolinska Institutet.
    Within-session effect of repeated stress exposure on extinction circuitry function in social anxiety disorder2017Inngår i: Psychiatry Research: Neuroimaging, ISSN 0925-4927, E-ISSN 1872-7506, Vol. 261, s. 85-90Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Anxiety reduction following repeated exposure to stressful experiences is generally held to depend on neural processes involved in extinction of conditioned fear. We predicted that repeated exposure to stressful experiences would change activity throughout the circuitry serving extinction, including ventromedial prefrontal cortex (vmPFC), the hippocampus and the amygdala. To test this prediction, 36 participants diagnosed with SAD performed two successive speeches in front of an observing audience while regional cerebral blood flow (rCBF) was recorded using positron emission tomography. To control for non-anxiolytic effects of repeated exposure, rCBF was also measured during repeated presentations of neutral and angry facial expressions. Results showed that anxiety ratings and heart rate decreased from the first to the second speech, indicating an anxiolytic effect of repeated exposure. Exposure attenuated rCBF in the amygdala whereas no change in rCBF was observed in the vmPFC or hippocampus. The rCBF-reductions in the amygdala were greater following repetition of the speech task than repetition of face exposure indicating that they were specific to anxiety attenuation and not due to a reduced novelty. Our findings suggest that amygdala-related attenuation processes are key to understanding the working mechanisms of exposure therapy.

    Fulltekst (pdf)
    fulltext
  • 114.
    Åhs, Fredrik
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi. Duke Univ, Ctr Cognit Neurosci, Durham, NC 27708 USA.;Karolinska Inst, Dept Clin Neurosci, Stockholm, Sweden..
    Kragel, Philip A.
    Duke Univ, Ctr Cognit Neurosci, Durham, NC 27708 USA..
    Zielinski, David J.
    Duke Univ, Pratt Sch Engn, Durham, NC 27708 USA..
    Brady, Rachael
    Duke Univ, Pratt Sch Engn, Durham, NC 27708 USA..
    LaBar, Kevin S.
    Duke Univ, Ctr Cognit Neurosci, Durham, NC 27708 USA..
    Medial prefrontal pathways for the contextual regulation of extinguished fear in humans2015Inngår i: NeuroImage, ISSN 1053-8119, E-ISSN 1095-9572, Vol. 122, s. 262-271Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The maintenance of anxiety disorders is thought to depend, in part, on deficits in extinction memory, possibly due to reduced contextual control of extinction that leads to fear renewal. Animal studies suggest that the neural circuitry responsible fear renewal includes the hippocampus, amygdala, and dorsomedial (dmPFC) and ventromedial (vmPFC) prefrontal cortex. However, the neural mechanisms of context-dependent fear renewal in humans remain poorly understood. We used functional magnetic resonance imaging (fMRI), combined with psychophysiology and immersive virtual reality, to elucidate how the hippocampus, amygdala, and dmPFC and vmPFC interact to drive the context-dependent renewal of extinguished fear. Healthy human participants encountered dynamic fear-relevant conditioned stimuli (CSs) while navigating through 3-D virtual reality environments in the MRI scanner. Conditioning and extinction were performed in two different virtual contexts. Twenty-four hours later, participants were exposed to the CSs without reinforcement while navigating through both contexts in the MRI scanner. Participants showed enhanced skin conductance responses (SCRs) to the previously-reinforced CS + in the acquisition context on Day 2, consistent with fear renewal, and sustained responses in the dmPFC. In contrast, participants showed low SCRs to the CSs in the extinction context on Day 2, consistent with extinction recall, and enhanced vmPFC activation to the non-reinforced CS -. Structural equation modeling revealed that the dmPFC fully mediated the effect of the hippocampus on right amygdala activity during fear renewal, whereas the vmPFC partially mediated the effect of the hippocampus on right amygdala activity during extinction recall. These results indicate dissociable contextual influences of the hippocampus on prefrontal pathways, which, in turn, determine the level of reactivation of fear associations.

  • 115.
    Åhs, Fredrik
    et al.
    Uppsala Universitet.
    Kumlien, Eva
    Uppsala University Hospital.
    Fredrikson, Mats
    Uppsala Universitet.
    Arousal enhanced memory retention is eliminated following temporal lobe resection2010Inngår i: Brain and Cognition, ISSN 0278-2626, E-ISSN 1090-2147, Vol. 73, nr 3, s. 176-179Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The amygdala, situated in the anterior medial temporal lobe (MTL), is involved in the emotional enhancement of memory. The present study evaluated whether anterior MTL-resections attenuated arousal induced memory enhancement for pictures. Also, the effect of MTL-resections on response latencies at retrieval was assessed. Thirty-one patients with unilateral MTL-resections (17 left, 14 right) together with 16 controls participated in a forced choice memory task with pictorial stimuli varying in arousal. Response latencies increased with stimulus arousal in controls but not in patients. This was paralleled by attenuated recognition memory for moderately and highly arousing pictures in MTL-resectioned patients as compared to healthy controls. However, patients and controls did not differ in memory performance for non-arousing pictures. These results suggest that the MTL is necessary for arousal induced memory enhancement.

  • 116.
    Åhs, Fredrik
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Michelgård, Åsa
    Fredrikson, Mats
    Wolf, O.T.
    Kirschbaum, C.
    Appel, Lieuwe
    Furmark, Tomas
    Central neural correlates of salivary cortisol during stress in subjects with social phobia2004Inngår i: Biological Psychiatry, 55, Suppl. 8, 2004, s. 211S-Konferansepaper (Fagfellevurdert)
  • 117.
    Åhs, Fredrik
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Michelgård, Åsa
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Fredrikson, Mats
    Wolf, O.T.
    Kirschbaum, C.
    Appel, Lieuwe
    Furmark, Tomas
    Central neural correlates of salivary cortisol in social phobics performing a speech2003Inngår i: Psychophysiology, 40, Suppl. 1, 2003, s. S21-Konferansepaper (Fagfellevurdert)
  • 118.
    Åhs, Fredrik
    et al.
    Center for Cognitive Neuroscience, Duke University, United States.
    Miller, Stacie S
    Monell Chemical Senses Center, Philadelphia, United States.
    Gordon, Amy R
    Monell Chemical Senses Center, Philadelphia, United States; Dept. of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden.
    Lundström, Johan N
    Monell Chemical Senses Center, Philadelphia, United States; Dept. of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden; Dept. of Psychology, University of Pennsylvania, Philadelphia, United States.
    Aversive learning increases sensory detection sensitivity2013Inngår i: Biological Psychology, ISSN 0301-0511, E-ISSN 1873-6246, Vol. 92, nr 2, s. 135-41, artikkel-id S0301-0511(12)00249-9Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Increased sensitivity to specific cues in the environment is common in anxiety disorders. This increase in sensory processing can emerge through attention processes that enhance discrimination of a cue from other cues as well as through augmented senses that reduce the absolute intensity of sensory stimulation needed for detection. Whereas it has been established that aversive conditioning can enhance odor quality discrimination, it is not known whether it also changes the absolute threshold at which an odor can be detected. In two separate experiments, we paired one odor of an indistinguishable odor pair with an aversive outcome using a classical conditioning paradigm. Ability to discriminate and to detect the paired odor was assessed before and after conditioning. The results demonstrate that aversive conditioning increases absolute sensory sensitivity to a predictive odor cue in an odor-specific manner, rendering the conditioned odor detectable at a significantly lower (20%) absolute concentration. As animal research has found long-lasting change in behavior and neural signaling resulting from conditioning, absolute threshold was also tested eight weeks later. Detection threshold had returned to baseline level at the eight week follow-up session suggesting that the change in detection threshold was mediated by a transient reorganization. Taken together, we can for the first time demonstrate that increasing the biological salience of a stimulus augments the individual's absolute sensitivity in a stimulus-specific manner outside conscious awareness. These findings provide a unique framework for understanding sensory mechanisms in anxiety disorders as well as further our understanding of mechanisms underlying classical conditioning.

  • 119.
    Åhs, Fredrik
    et al.
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för psykologi och socialt arbete.
    Mozelius, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för data- och systemvetenskap.
    Dobslaw, Felix
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för data- och systemvetenskap.
    Artificial Intelligence Supported Cognitive Behavioral Therapy for Treatment of Speech Anxiety in Virtual Reality Environments2020Inngår i: Proceedings of the European Conference on the Impact of Artificial Intelligence and Robotics / [ed] Florinda Matos, Reading, UK: Academic Conferences and Publishing International Limited, 2020, Vol. 2Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Cognitive behavioral therapy (CBT) has become a successful treatment to improve management of stress and anxiety in social situations. One of the most widespread social anxiety disorders is speech anxiety, and there are also studies reporting that speech anxiety is increasing among younger adults. An emerging trend in CBT treatment is virtual reality (VR), a technology that today also could involve the use of artificial intelligence. The aim of this position paper is to present and discuss the idea of using explainable artificial intelligence to improve CBT treatment of speech anxiety in virtual reality environments.  

    The proposed CBT and VR concept builds upon identification of individuals for whom a scientifically grounded treatment can be predicted to have a larger effect than the average. The identification of these individuals should be conducted with the use of Explainable artificial intelligence (XAI). However, the effect of providing XAI-based information on actual treatment outcome has not been fully investigated and established. To better understand how AI-based information can strengthen CBT, it would be valuable to investigate how much confidence individuals undergoing treatment can have in information that is derived from XAI applications. If XAI-derived information is trusted to the same extent as traditional information coming from psychologists, this could open up for CBT design.

    Furthermore, the VR-treatment should be grounded in learning theory and cognitive psychology with an emphasis on promotion of inhibitory learning.  A commercial application should be used for stimuli presentation in the VR-head-set based on various scenarios that simulates real-world situations. The main objective of the VR-treatment is to promote inhibitory learning by disproving catastrophic beliefs through exposure to distressful speech situations. Outcomes of the treatment should primarily be measured by the Public Speaking Anxiety Scale, but also involve an assessment of social anxiety with the use of Liebowitz’s Social Anxiety Scale.

    Fulltekst (pdf)
    fulltext
  • 120.
    Åhs, Fredrik
    et al.
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för psykologi och socialt arbete.
    Mozelius, Peter
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för data- och systemvetenskap.
    Espvall, Majen
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för psykologi och socialt arbete.
    Preparing Psychologists and Social Workers for the Daily Use of AI2022Inngår i: Proceedings of European Conference on the Impact of AI and Robotics, Academic Conferences and Publishing International Limited, 2022, Vol. 4, s. 1-5Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A daily use of Artificial Intelligence (AI) is becoming a fact in many fields today, and two of them are psychology and social work. At the same time as AI systems are used for predicting psychological treatments and for decisions in social welfare, the university has no AI courses for these professions. Moreover, there are several examples in these fields where AI can make unethical decisions that need to be corrected by humans. To better understand the possibilities and challenges of AI in psychology and social work, professional users of AI services need a tailored education on how the underlying technology works. The aim of this paper is to present a project concept for the design and evaluation of a novel course in AI for professional development in psychology and social work. For the design and development of the course the guiding research question should be: What are the strengths and challenges with contemporary AI techniques regarding prediction, adaptivity and decision systems? The suggested AI course should be given as a technology enhanced online training to enable the idea of anytime and anywhere for full-time working participants. Course content and activities are divided into the four separate sections of: 1) An introduction of the AI history is structured around the so called 'Three waves of AI', and with o focus on the current third wave. 2) A section with a focus on AI techniques for prediction and adaptivity. Underlying techniques such as machine learning, neural networks, and deep learning will be conceptually described and discussed, but not on a detailed level. 3) An elaborated discussion on the relevance, usefulness and trust, and the at the difference between AI-based decision systems and AI-based decision support systems. 4) Finally, the fourth section should comprise the ethical aspects of AI, and discuss transparency and Explainable AI. An innovative approach of the project is to use a neuroscientific assessment of the education to understand how the education changes brain function relevant to evaluate AI based decision. This should be complemented with a qualitative evaluation based on semi-structured interviews.

  • 121.
    Åhs, Fredrik
    et al.
    Department of Psychology, Uppsala University, Uppsala, Sweden.
    Pissiota, Anna
    Unit for Transcultural Psychiatry, Uppsala University, Uppsala, Sweden.
    Michelgård, Åsa
    Department of Clinical Neuroscience, Uppsala University, Uppsala, Sweden.
    Frans, Örjan
    Department of Psychology, Uppsala University, Uppsala, Sweden.
    Furmark, Tomas
    Department of Psychology, Uppsala University, Uppsala, Sweden.
    Appel, Lieuwe
    Uppsala Imanet, GE Healthcare, Uppsala, Sweden.
    Fredrikson, Mats
    Department of Psychology, Uppsala University, Uppsala, Sweden.
    Disentangling the web of fear: amygdala reactivity and functional connectivity in spider and snake phobia2009Inngår i: Psychiatry Research, ISSN 0165-1781, E-ISSN 1872-7123, Vol. 172, nr 2, s. 103-108Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The objective was to study effects of fear on brain activity, functional connectivity and brain-behavior relationships during symptom provocation in subjects with specific phobia. Positron emission tomography (PET) and (15)O water was used to measure regional cerebral blood flow (rCBF) in 16 women phobic of either snakes or spiders but not both. Subjects watched pictures of snakes and spiders serving either as phobic or fear-relevant, but non-phobic, control stimuli depending on phobia type. Presentation of phobic as compared with non-phobic cues was associated with increased activation of the right amygdala and cerebellum as well as the left visual cortex and circumscribed frontal areas. Activity decreased in the prefrontal, orbitofrontal and ventromedial cortices as well as in the primary somatosensory cortex and auditory cortices. Furthermore, amygdala activation correlated positively with the subjective experience of distress. Connectivity analyses of activity in the phobic state revealed increased functional couplings between voxels in the right amygdala and the periamygdaloid area, fusiform gyrus and motor cortex. During non-phobic stimulation, prefrontal activity correlated negatively with amygdala rCBF, suggesting a phobia-related functional decoupling. These results suggest that visually elicited phobic reactions activate object recognition areas and deactivate prefrontal areas involved in cognitive control over emotion-triggering areas like the amygdala, resulting in motor readiness to support fight or flight.

  • 122.
    Åhs, Fredrik
    et al.
    Department of Psychology, Uppsala University, Uppsala, Sweden; Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    Rosén, Jörgen
    Department of Psychology, Uppsala University, Uppsala, Sweden.
    Kastrati, Granit
    Department of Psychology, Uppsala University, Uppsala, Sweden; Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    Fredrikson, Mats
    Department of Psychology, Uppsala University, Uppsala, Sweden; Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    Agren, Thomas
    Department of Psychology, Uppsala University, Uppsala, Sweden.
    Lundström, Johan N
    Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden; Monell Chemical Senses Center, Philadelphia, PA, United States; Department of Psychology, University of Pennsylvania, Philadelphia, United States.
    Biological preparedness and resistance to extinction of skin conductance responses conditioned to fear relevant animal pictures: A systematic review2018Inngår i: Neuroscience and Biobehavioral Reviews, ISSN 0149-7634, E-ISSN 1873-7528, Vol. 95, s. 430-437, artikkel-id S0149-7634(18)30456-1Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Preparedness theory is one of the most influential ideas in explaining the origin of specific phobias. The theory proposes that fear conditioning is selective to animals that have posed a threat to survival throughout human evolution, and that acquired fear memories to such threats are resistant to extinction. We reviewed fear conditioning studies testing whether autonomic responses conditioned to pictures of snakes and spiders show greater resistance to extinction than neutral cues. We identified 32 fear conditioning experiments published in 23 studies including 1887 participants. Increased resistance to extinction of conditioned responses to snake and spider pictures was found in 10 (31%) of the experiments, whereas 22 (69%) experiments did not support the hypothesis. Thus, the body of evidence suggests that preparedness theory does not explain the origin of specific phobias.

  • 123.
    Åhs, Fredrik
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi. Karolinska Inst, Dept Clin Neurosci, Stockholm, Sweden.
    Rosén, Jörgen
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Kastrati, Granit
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi. Karolinska Inst, Dept Clin Neurosci, Stockholm, Sweden.
    Fredrikson, Mats
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi. Karolinska Inst, Dept Clin Neurosci, Stockholm, Sweden.
    Ågren, Thomas
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Lundstrom, Johan N.
    Karolinska Inst, Dept Clin Neurosci, Stockholm, Sweden;Monell Chem Senses Ctr, 3500 Market St, Philadelphia, PA 19104 USA;Univ Penn, Dept Psychol, 3815 Walnut St, Philadelphia, PA 19104 USA.
    Biological preparedness and resistance to extinction of skin conductance responses conditioned to fear relevant animal pictures: A systematic review2018Inngår i: Neuroscience and Biobehavioral Reviews, ISSN 0149-7634, E-ISSN 1873-7528, Vol. 95, s. 430-437Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Preparedness theory is one of the most influential ideas in explaining the origin of specific phobias. The theory proposes that fear conditioning is selective to animals that have posed a threat to survival throughout human evolution, and that acquired fear memories to such threats are resistant to extinction. We reviewed fear conditioning studies testing whether autonomic responses conditioned to pictures of snakes and spiders show greater resistance to extinction than neutral cues. We identified 32 fear conditioning experiments published in 23 studies including 1887 participants. Increased resistance to extinction of conditioned responses to snake and spider pictures was found in 10 (31%) of the experiments, whereas 22 (69%) experiments did not support the hypothesis. Thus, the body of evidence suggests that preparedness theory does not explain the origin of specific phobias.

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