TY - JOUR A1 - Wiebking, Christine A1 - de Greck, Moritz A1 - Duncan, Niall W. A1 - Tempelmann, Claus A1 - Bajbouj, Malek A1 - Northoff, Georg T1 - Interoception in insula subregions as a possible state marker for depression BT - an exploratory fMRI study investigating healthy, depressed and remitted participants JF - Frontiers in behavioral neuroscience N2 - Background: Interoceptive awareness (iA), the awareness of stimuli originating inside the body, plays an important role in human emotions and psychopathology. The insula is particularly involved in neural processes underlying iA. However, iA-related neural activity in the insula during the acute state of major depressive disorder (MDD) and in remission from depression has not been explored. Methods: A well-established fMRI paradigm for studying (iA; heartbeat counting) and exteroceptive awareness (eA; tone counting) was used. Study participants formed three independent groups: patients suffering from MDD, patients in remission from MDD or healthy controls. Task-induced neural activity in three functional subdivisions of the insula was compared between these groups. Results: Depressed participants showed neural hypo-responses during iA in anterior insula regions, as compared to both healthy and remitted participants. The right dorsal anterior insula showed the strongest response to iA across all participant groups. In depressed participants there was no differentiation between different stimuli types in this region (i.e., between iA, eA and noTask). Healthy and remitted participants in contrast showed clear activity differences. Conclusions: This is the first study comparing iA and eA-related activity in the insula in depressed participants to that in healthy and remitted individuals. The preliminary results suggest that these groups differ in there being hypo-responses across insula regions in the depressed participants, whilst non-psychiatric participants and patients in remission from MDD show the same neural activity during iA in insula subregions implying a possible state marker for MDD. The lack of activity differences between different stimulus types in the depressed group may account for their symptoms of altered external and internal focus. KW - major depressive disorder KW - interoceptive awareness KW - insula KW - remission KW - neuroimaging KW - fMRI KW - hopelessness KW - interoception Y1 - 2015 U6 - https://doi.org/10.3389/fnbeh.2015.00082 SN - 1662-5153 IS - 9 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Wiebking, Christine A1 - de Greck, Moritz A1 - Duncan, Niall W. A1 - Tempelmann, Claus A1 - Bajbouj, Malek A1 - Northoff, Georg T1 - Interoception in insula subregions as a possible state marker for depression - an exploratory fMRI study investigating healthy, depressed and remitted participants JF - Frontiers in behavioral neuroscience N2 - Background: Interoceptive awareness, the awareness of stimuli originating inside the body, plays an important role in human emotions and psychopathology. The insula is particularly involved in neural processes underlying iA. However, iA-related neural activity in the insula during the acute state of major depressive disorder (MDD) and in remission from depression has not been explored. Methods: A well-established fMRI paradigm for studying interoceptive awareness (iA; heartbeat counting) and exteroceptive awareness (eA; tone counting) was used. Study participants formed three independent groups: patients suffering from MDD, patients in remission from MDD or healthy controls. Task-induced neural activity in three functional subdivisions of the insula was compared between these groups. Results: Depressed participants showed neural hypo-responses during iA in anterior insula regions, as compared to both healthy and remitted participants. The right dorsal anterior insula showed the strongest response to iA across all participant groups. In depressed participants there was no differentiation between different stimuli types in this region (i.e., between iA, eA and noTask). Healthy and remitted participants in contrast showed clear activity differences. Conclusions: This is the first study comparing iA and eA-related activity in the insula in depressed participants to that in healthy and remitted individuals. The preliminary results suggest that these groups differ in there being hypo-responses across insula regions in the depressed participants, whilst healthy participants and patients in remission from MDD show the same neural activity during iA in insula subregions implying a possible state marker for MDD. The lack of activity differences between different stimulus types in the depressed group may account for their symptoms of altered external and internal focus. KW - major depressive disorder KW - interoceptive awareness KW - insula KW - remission KW - neuroimaging KW - fMRI Y1 - 2015 U6 - https://doi.org/10.3389/fnbeh.2015.00082 SN - 1662-5153 VL - 9 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Wiebking, Christine A1 - Northoff, Georg T1 - Neural activity during interoceptive awareness and its associations with alexithymia BT - An fMRI study in major depressive disorder and non-psychiatric controls JF - Frontiers in psychology N2 - Objective: Alexithymia relates to difficulties recognizing and describing emotions. It has been linked to subjectively increased interoceptive awareness (IA) and to psychiatric illnesses such as major depressive disorder (MDD) and somatization. MDD in turn is characterized by aberrant emotion processing and IA on the subjective as well as on the neural level. However, a link between neural activity in response to IA and alexithymic traits in health and depression remains unclear. Methods: A well-established fMRI task was used to investigate neural activity during IA (heartbeat counting) and exteroceptive awareness (tone counting) in non-psychiatric controls (NC) and MDD. Firstly, comparing MDD and NC, a linear relationship between IA-related activity and scores of the Toronto Alexithymia Scale (TAS) was investigated through whole-brain regression. Secondly, NC were divided by median-split of TAS scores into groups showing low (NC-low) or high (NC-high) alexithymia. MDD and NC-high showed equally high TAS scores. Subsequently, IA-related neural activity was compared on a whole-brain level between the three independent samples (MDD, NC-low, NC-high). Results: Whole-brain regressions between MDD and NC revealed neural differences during IA as a function of TAS-DD (subscale difficulty describing feelings) in the supragenual anterior cingulate cortex (sACC; BA 24/32), which were due to negative associations between TAS-DD and IA-related activity in NC. Contrasting NC subgroups after median-split on a whole-brain level, high TAS scores were associated with decreased neural activity during IA in the sACC and increased insula activity. Though having equally high alexithymia scores, NC-high showed increased insula activity during IA compared to MDD, whilst both groups showed decreased activity in the sACC. Conclusions: Within the context of decreased sACC activity during IA in alexithymia (NC-high and MDD), increased insula activity might mirror a compensatory mechanism in NC-high, which is disrupted in MDD. KW - major depressive disorder KW - alexithymia KW - interoceptive awareness KW - insula KW - sACC KW - fMRI KW - neuroimaging Y1 - 2015 U6 - https://doi.org/10.3389/fpsyg.2015.00589 SN - 1664-1078 VL - 6 IS - 589 PB - Frontiers Research Foundation ER - TY - JOUR A1 - Wiebking, Christine A1 - Northoff, Georg T1 - Neural activity during interoceptive awareness and its associations with alexithymia-An fMRI study in major depressive disorder and non-psychiatric controls JF - Frontiers in psychology N2 - Objective: Alexithymia relates to difficulties recognizing and describing emotions. It has been linked to subjectively increased interoceptive awareness (IA) and to psychiatric illnesses such as major depressive disorder (MDD) and somatization. MDD in turn is characterized by aberrant emotion processing and IA on the subjective as well as on the neural level. However, a link between neural activity in response to IA and alexithymic traits in health and depression remains unclear. Methods: A well-established fMRI task was used to investigate neural activity during IA (heartbeat counting) and exteroceptive awareness (tone counting) in non-psychiatric controls (NC) and MDD. Firstly, comparing MDD and NC, a linear relationship between IA-related activity and scores of the Toronto Alexithymia Scale (TAS) was investigated through whole-brain regression. Secondly, NC were divided by median-split of TAS scores into groups showing low (NC-low) or high (NC-high) alexithymia. MDD and NC-high showed equally high TAS scores. Subsequently, IA-related neural activity was compared on a whole-brain level between the three independent samples (MDD, NC-low, NC-high). Results: Whole-brain regressions between MDD and NC revealed neural differences during IA as a function of TAS-DD (subscale difficulty describing feelings) in the supragenual anterior cingulate cortex (sACC; BA 24/32), which were due to negative associations between TAS-DD and IA-related activity in NC. Contrasting NC subgroups after median-split on a whole-brain level, high TAS scores were associated with decreased neural activity during IA in the sACC and increased insula activity. Though having equally high alexithymia scores, NC-high showed increased insula activity during IA compared to MDD, whilst both groups showed decreased activity in the sACC. Conclusions: Within the context of decreased sACC activity during IA in alexithymia (NC-high and MDD), increased insula activity might mirror a compensatory mechanism in NC-high, which is disrupted in MDD. KW - major depressive disorder KW - alexithymia KW - interoceptive awareness KW - insula KW - sACC KW - interoception KW - fMRI KW - neuroimaging Y1 - 2015 U6 - https://doi.org/10.3389/fpsyg.2015.00589 SN - 1664-1078 VL - 6 PB - Frontiers Research Foundation CY - Lausanne ER -