Project description:Background: Attention-deficit/hyperactivity disorder (ADHD) is presumed to involve mental effort application difficulties. To test this assumption, we manipulated task difficulty and measured behavioral, as well as subjective and psychophysiological indices of effort. Methods: Fifteen adolescent ADHD boys and 16 controls performed two tasks. First, subjective estimates and behavioral and pupillary measures of effort were recorded across five levels of N-back task difficulties. Second, effort discounting was assessed. In the latter, participants made repeated choices between performing a difficult N-back task for a high reward versus an easier N-back task for a smaller reward. Results: Increasing task difficulty led to similar deteriorations in performance for both groups - although ADHD participants performed more poorly at all difficulty levels than controls. While ADHD and control participants rated the tasks equally difficult and discounted effort similarly, those with ADHD displayed slightly different pupil dilation patterns with increasing task difficulty. Conclusion: The behavioral results did not provide evidence for mental effort problems in adolescent boys with ADHD. The subtle physiological effects, however, suggest that adolescents with ADHD may allocate effort in a different way than controls.
Project description:Frontotemporal dementia (FTD), a neurodegenerative disease broadly characterized by socioemotional impairments, includes three clinical subtypes: behavioral variant FTD (bvFTD), semantic variant primary progressive aphasia (svPPA) and non-fluent variant primary progressive aphasia (nfvPPA). Emerging evidence has shown emotional reactivity impairments in bvFTD and svPPA, whereas emotional reactivity in nfvPPA is far less studied. In 105 patients with FTD (49 bvFTD, 31 svPPA and 25 nfvPPA) and 27 healthy controls, we examined three aspects of emotional reactivity (physiology, facial behavior and subjective experience) in response to a sad film. In a subset of the sample, we also examined the neural correlates of diminished aspects of reactivity using voxel-based morphometry. Results indicated that all three subtypes of FTD showed diminished physiological responding in respiration rate and diastolic blood pressure; patients with bvFTD and svPPA also showed diminished subjective experience, and no subtypes showed diminished facial behavior. Moreover, there were differences among the clinical subtypes in brain regions where smaller volumes were associated with diminished sadness reactivity. These results show that emotion impairments extend to sadness reactivity in FTD and underscore the importance of considering different aspects of sadness reactivity in multiple clinical subtypes for characterizing emotional deficits and associated neurodegeneration in FTD.
Project description:The emotional properties of words, such as valence and arousal, influence the way we perceive and process verbal stimuli. Recently, subjective significance was found to be an additional factor describing the activational aspect of emotional reactions, which is vital for the cognitive consequences of emotional stimuli processing. Subjective significance represents the form of mental activation specific to reflective mind processing. The Lexical Decision Task (LDT) is a paradigm allowing the investigation of the involuntary processing of meaning and differentiating this processing from the formal processing of the perceptual features of words. In this study, we wanted to search for the consequences of valence, arousal, and subjective significance for the involuntary processing of verbal stimuli meaning indexed by both behavioral measures (reaction latencies) and electrophysiological measures (Event-Related Potentials: ERPs). We expected subjective significance, as the reflective form of activation, to shorten response latencies in LDT. We also expected subjective significance to modulate the amplitude of the ERP FN400 component, reducing the negative-going deflection of the potential. We expected valence to shape the LPC component amplitude, differentiating between negative and positive valences, since the LPC indexes the meaning processing. Indeed, the results confirmed our expectations and showed that subjective significance is a factor independent from the arousal and valence that shapes the involuntary processing of verbal stimuli, especially the detection of a link between stimulus and meaning indexed by the FN400. Moreover, we found that the LPC amplitude was differentiated by valence level.
Project description:ObjectivesThe aim of this preliminary study was to evaluate if Sleep Restriction Therapy for insomnia is associated with modifications to physiological arousal, indexed through overnight measures of plasma cortisol concentrations and core body temperature.MethodsIn a pre-to-post open label study design, eleven patients with chronic and severe Psychophysiological Insomnia underwent 5 weeks of Sleep Restriction Therapy.ResultsEight (73%) patients out of 11 consented completed therapy and showed a decrease in insomnia severity pre-to-post treatment (mean (SD): 18.1 (2.8) versus 8.4 (4.8); p = .001). Six patients were analyzed with pre-to-post overnight measures of temperature and cortisol. Contrary to our hypothesis, significantly higher levels of plasma cortisol concentrations were found during the early morning at post-treatment compared to baseline (p < .01), while no change was observed in the pre-sleep phase or early part of the night. Core body temperature during sleep was however reduced significantly (overall mean [95% CI]: 36.54 (°C) [36.3, 36.8] versus 36.45 [36.2, 36.7]; p < .05).ConclusionsSleep Restriction Therapy therefore was associated with increased early morning cortisol concentrations and decreased core body temperature, supporting the premise of physiological changes in functioning after effective therapy. Future work should evaluate change in physiological variables associated with clinical treatment response.Trial registrationAustralian New Zealand Clinical Trials Registry ANZCTR 12612000049875.
Project description:Mental imagery is known to play a key role in the development and maintenance of depression and anxiety. Prisoners commonly experience psychological distress, but interventions to address this are currently lacking. We aimed to examine the link between prospective mental imagery and anxiety and depression among prisoners. One hundred twenty-three male prisoners from a Category C prison in southwest England participated in the study. They completed the Centre for Epidemiologic Studies Depression Scale (CES-D) and the General Anxiety Disorder Scale (GAD-7) to measure whether they experience depression and/or anxiety symptoms. Furthermore, they completed additional questionnaires to evaluate their prospective mental imagery. Results showed that 67.5% of prisoners presented with more depression symptoms and 27.7% with more anxiety symptoms. Supporting earlier findings, our data revealed that some dimensions of prospective mental imagery were significantly related with increased anxiety and depression symptoms in prisoners. Namely, intrusive negative personally relevant imagery was a positive predictor and likelihood of positive events a negative predictor of both anxiety and depression symptoms. The perceived likelihood of negative events was a positive predictor of depression. Intrusive verbal thought was a positive predictor of anxiety. The obtained results suggest the need to develop interventions not only targeting the reduction of prospective negative imagery but also the enhancement of positive mental imagery.
Project description:Vigilance usually deteriorates over prolonged driving at non-optimal times of day. Exposure to blue-enriched light has shown to enhance arousal, leading to behavioral benefits in some cognitive tasks. However, the cognitive effects of long-wavelength light have been less studied and its effects on driving performance remained to be addressed. We tested the effects of a blue-enriched white light (BWL) and a long-wavelength orange light (OL) vs. a control condition of dim light on subjective, physiological and behavioral measures at 21:45 h. Neurobehavioral tests included the Karolinska Sleepiness Scale and subjective mood scale, recording of distal-proximal temperature gradient (DPG, as index of physiological arousal), accuracy in simulated driving and reaction time in the auditory psychomotor vigilance task. The results showed that BWL decreased the DPG (reflecting enhanced arousal), while it did not improve reaction time or driving performance. Instead, blue light produced larger driving errors than OL, while performance in OL was stable along time on task. These data suggest that physiological arousal induced by light does not necessarily imply cognitive improvement. Indeed, excessive arousal might deteriorate accuracy in complex tasks requiring precision, such as driving.
Project description:Gender differences in adolescents' mental health problems have been extensively reported. Yet, there is limited research in exploring longitudinal trends in mental health and wellbeing between boys and girls. This study investigated any emerging developmental trends of gender differences in mental health problems and subjective wellbeing for young people from early to mid-adolescence in England. A longitudinal group of 8612 young people's mental health and subjective wellbeing trajectories were investigated between the period of ages 11/12 and 13/14. Mental health difficulties and subjective wellbeing were measured using the child self-report Strengths and Difficulties Questionnaire (SDQ) and Short Warwick and Edinburgh Wellbeing Scale (SWEMWBS), respectively. Any gender difference in the change of adolescents' mental health and subjective wellbeing over 3 year period were estimated using multi-level regression while accounting for various socio-demographic and resilience factors. Young people are at increased risk of mental health problems between the ages of 11 and 14, particularly girls. The overall difficulty levels reported by girls were significantly higher than boys across a range of mental health problems and subjective wellbeing. These developmental trends persisted after controlling for a broad range of potential confounders. Young people has shown clear signs of mental distress as they get older. This escalation was particularly evident among girls. Distress can come at the time of significant physical, emotional, and social changes in an adolescents' life, and can be heightened during secondary school transition. This evidence highlights the importance of early intervention to reduce risk of distress.
Project description:Previous studies have shed light on the importance of affect in risk perception and the role of mental imagery in generating affect. In the current study, we explore the causal relationship between mental imagery, affect, and risk perception by systematically varying the level of mental imagery in three levels (i.e., enhanced, spontaneous, or prevented). In light of the increasing environmental risk of adverse events caused by climate change, we operationalize risk as participants' perceived risk of climate change. One-thousand-fifty-five participants were recruited online and randomized to one of three levels of mental imagery. As predicted, we found a causal link between the level of mental imagery, affective experience, and perceived risk of climate change, in that enhanced mental imagery caused a larger decrease in positive affective valence and a larger increase in perceived risk of climate change. We argue that mental imagery enhances the negative affect associated with the risk event by creating a perceptual experience that mimics seeing the environmental risk events.
Project description:Research on emotional perception and learning indicates appetitive cues engage nucleus accumbens (NAc) and medial prefrontal cortex (mPFC), whereas amygdala activity is modulated by the emotional intensity of appetitive and aversive cues. This study sought to determine patterns of functional activation and connectivity among these regions during narrative emotional imagery. Using event-related fMRI, we investigate activation of these structures when participants vividly imagine pleasant, neutral, and unpleasant scenes. Results indicate that pleasant imagery selectively activates NAc and mPFC, whereas amygdala activation was enhanced during both pleasant and unpleasant imagery. NAc and mPFC activity were each correlated with the rated pleasure of the imagined scenes, while amygdala activity was correlated with rated emotional arousal. Functional connectivity of NAc and mPFC was evident throughout imagery, regardless of hedonic content, while correlated activation of the amygdala with NAc and mPFC was specific to imagining pleasant scenes. These findings provide strong evidence that pleasurable text-driven imagery engages a core appetitive circuit, including NAc, mPFC, and the amygdala.
Project description:Making the inevitability of mortality salient makes people more defensive about their self-esteem and worldviews. Theoretical arguments and empirical evidence point to a mediating role of arousal in this defensive process, but evidence from physiological measurement studies is scarce and inconclusive. The present study seeks to draw a comprehensive picture of how physiological arousal develops over time in the mortality salience (MS) paradigm, and whether contemplating one's mortality actually elicits more physiological arousal than reflecting on a death-unrelated aversive control topic. In a between-subjects design, participants were asked two open questions about their mortality or about dental pain. Cardiac, respiratory, and electrodermal indicators of arousal were measured both as participants provided written answers to the questions, and during a series of resting intervals surrounding the questions. A Bayes factor analysis indicated support for the hypothesis that the MS paradigm increases physiological arousal, both while answering the two open-ended questions and afterward. Regarding the MS versus dental pain comparison, the null hypothesis of no difference was supported for most analysis segments and signals. The results indicate that the arousal elicited by MS is not different from that elicited by dental pain salience. This speaks against the idea that worldview defense following MS occurs because MS produces higher physiological arousal. Of course, this finding does not rule the importance of other forms of arousal (i.e., subjective arousal) for MS effects.