Acute anxiety and autonomic arousal induced by CO 2 inhalation impairs prefrontal executive functions in healthy humans

Funder: The Wallitt Foundation; Eton College; and NIHR Cambridge Biodmedical Centre (BRC) Mental Health theme.Funder: Cambridge Vice-Chanchellor's Award and Fitzwilliam College scholarshipFunder: Medical Research Council (G1000183)Abstract: Acute anxiety impacts cognitive performance. Inhalation of air enriched with carbon dioxide (CO2) in healthy humans provides a novel experimental model of generalised anxiety, but has not previously been used to assess cognition. We used inhalation of 7.5% CO2 to induce acute anxiety and autonomic arousal in healthy volunteers during neuropsychological tasks of cognitive flexibility, emotional processing and spatial working memory in a single-blind, placebo-controlled, randomized, crossover, within-subjects study. In Experiment 1 (n = 44), participants made significantly more extra-dimensional shift errors on the Cambridge Neuropsychological Test Automated Battery (CANTAB) Intra-Extra Dimensional Set Shift task under CO2 inhalation compared with ‘normal’ air. Participants also had slower latencies when responding to positive words and made significantly more omission errors for negative words on the CANTAB Affective Go/No-go task. In Experiment 2 (n = 28), participants made significantly more total errors and had poorer heuristic search strategy on the CANTAB Spatial Working Memory task. In both experiments, CO2 inhalation significantly increased negative affect; state anxiety and fear; symptoms of panic; and systolic blood pressure/heart rate. Overall, CO2 inhalation produced robust anxiogenic effects and impaired fronto-executive functions of cognitive flexibility and working memory. Effects on emotional processing suggested a mood-congruent slowing in processing speed in the absence of a negative attentional bias. State-dependent effects of anxiety on cognitive-emotional interactions in the prefrontal cortex warrant further investigation

Acute anxiety and autonomic arousal induced by CO2 inhalation impairs prefrontal executive functions in healthy humans.

Acute anxiety impacts cognitive performance. Inhalation of air enriched with carbon dioxide (CO2) in healthy humans provides a novel experimental model of generalised anxiety, but has not previously been used to assess cognition. We used inhalation of 7.5% CO2 to induce acute anxiety and autonomic arousal in healthy volunteers during neuropsychological tasks of cognitive flexibility, emotional processing and spatial working memory in a single-blind, placebo-controlled, randomized, crossover, within-subjects study. In Experiment 1 (n = 44), participants made significantly more extra-dimensional shift errors on the Cambridge Neuropsychological Test Automated Battery (CANTAB) Intra-Extra Dimensional Set Shift task under CO2 inhalation compared with 'normal' air. Participants also had slower latencies when responding to positive words and made significantly more omission errors for negative words on the CANTAB Affective Go/No-go task. In Experiment 2 (n = 28), participants made significantly more total errors and had poorer heuristic search strategy on the CANTAB Spatial Working Memory task. In both experiments, CO2 inhalation significantly increased negative affect; state anxiety and fear; symptoms of panic; and systolic blood pressure/heart rate. Overall, CO2 inhalation produced robust anxiogenic effects and impaired fronto-executive functions of cognitive flexibility and working memory. Effects on emotional processing suggested a mood-congruent slowing in processing speed in the absence of a negative attentional bias. State-dependent effects of anxiety on cognitive-emotional interactions in the prefrontal cortex warrant further investigation

Systematic Review of Mental Health Problems and Violent Extremism

This systematic review assesses the impact of mental health problems upon attitudes, intentions and behaviours in the context of radicalisation and terrorism. We identified 25 studies that measured rates of mental health problems across 28 samples. The prevalence rates are heterogenous and range from 0% to 57%. If we pool the results of those samples (n = 19) purely focused upon confirmed diagnoses where sample sizes are known (n = 1705 subjects), the results suggest arate of 14.4% with aconfirmed diagnosis. Where studies relied upon wholly, or in some form, upon privileged access to police or judicial data, diagnoses occurred 16.96% of the time (n = 283 subjects). Where studies were purely focused upon open sources (n = 1089 subjects), diagnoses were present 9.82% of the time. We then explore (a) the types and rates of mental health disorders identified (b) comparison/control group studies (c) studies that explore causal roles of mental health problems and (d) other complex needs.This work was supported by Public Safety Canada [8000-18884], the Department of Home Affairs (Australia), and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No 758834)

Acute anxiety and autonomic arousal induced by CO2 inhalation impairs prefrontal executive functions in healthy humans

Acute anxiety impacts cognitive performance. Inhalation of air enriched with carbon dioxide (CO2) in healthy humans provides a novel experimental model of generalised anxiety, but has not previously been used to assess cognition. We used inhalation of 7.5% CO2 to induce acute anxiety and autonomic arousal in healthy volunteers during neuropsychological tasks of cognitive flexibility, emotional processing and spatial working memory in a single-blind, placebo-controlled, randomized, crossover, within-subjects study. In Experiment 1 (n = 44), participants made significantly more extra-dimensional shift errors on the Cambridge Neuropsychological Test Automated Battery (CANTAB) Intra-Extra Dimensional Set Shift task under CO2 inhalation compared with 'normal' air. Participants also had slower latencies when responding to positive words and made significantly more omission errors for negative words on the CANTAB Affective Go/No-go task. In Experiment 2 (n = 28), participants made significantly more total errors and had poorer heuristic search strategy on the CANTAB Spatial Working Memory task. In both experiments, CO2 inhalation significantly increased negative affect; state anxiety and fear; symptoms of panic; and systolic blood pressure/heart rate. Overall, CO2 inhalation produced robust anxiogenic effects and impaired fronto-executive functions of cognitive flexibility and working memory. Effects on emotional processing suggested a mood-congruent slowing in processing speed in the absence of a negative attentional bias. State-dependent effects of anxiety on cognitive-emotional interactions in the prefrontal cortex warrant further investigation

Reviewing the links between violent extremism and personality, personality disorders, and psychopathy

Many early published analyses of the terrorist placed psychopathy as the core explanatory variable for terrorist behaviour. This speculative opinion was derived mainly from popular culture, and the desire to attribute mental disorders to those committing such violent acts. Poor research designs and a lack of empiricism ultimately undermined these arguments in favour of terrorism being rooted in disorders of personality. Multiple studies supporting psychopathic and personality-level explanations were conducted in the absence of rigorous clinical diagnostic procedures. Despite the methodological issues, concluding remarks from this research continues to hold instinctive appeal across the research field. This incentivises a need for a rigorous synthesis of the evidence base. The objective of this systematic review is to assess the impact of personality upon attitudes, intentions, and behaviours in the context of radicalisation and terrorism. This paper follows the same systematic process as the Gill et al. paper in this special issue. However, we use the model to interrogate the existing empirical literature on personality and terrorism in terms of its coverage, common themes, methodological strengths and weaknesses and implications. The search strategy for the systematic review is based on the Campbell Collaboration method. Results and their implications are discussed

Reviewing the links between violent extremism and personality, personality disorders, and psychopathy

Many early published analyses of the terrorist placed psychopathy as the core explanatory variable for terrorist behaviour. This speculative opinion was derived mainly from popular culture, and the desire to attribute mental disorders to those committing such violent acts. Poor research designs and a lack of empiricism ultimately undermined these arguments in favour of terrorism being rooted in disorders of personality. Multiple studies supporting psychopathic and personality-level explanations were conducted in the absence of rigorous clinical diagnostic procedures. Despite the methodological issues, concluding remarks from this research continues to hold instinctive appeal across the research field. This incentivises a need for a rigorous synthesis of the evidence base. The objective of this systematic review is to assess the impact of personality upon attitudes, intentions, and behaviours in the context of radicalisation and terrorism. This paper follows the same systematic process as the Gill et al. paper in this special issue. However, we use the model to interrogate the existing empirical literature on personality and terrorism in terms of its coverage, common themes, methodological strengths and weaknesses and implications. The search strategy for the systematic review is based on the Campbell Collaboration method. Results and their implications are discussed