ABSTRACT
BACKGROUND: Childhood maltreatment (CM) is associated with neurobiological aberrations and atypical social cognition. Few studies have examined the neural effects of another common early-life interpersonal stressor, namely peer victimisation (PV). This study examines the associations between tract aberrations and childhood interpersonal stress from caregivers (CM) and peers (PV), and explores how the observed tract alterations are in turn related to affective theory of mind (ToM). METHODS: Data from 107 age-and gender-matched youths (34 CM [age = 19.9 ± 1.68; 36%male], 35 PV [age = 19.9 ± 1.65; 43%male], 38 comparison subjects [age = 20.0 ± 1.66; 42%male] were analysed using tractography and whole-brain tract-based spatial statistics (TBSS). RESULTS: At the whole-brain level using TBSS, the CM group had higher fractional anisotropy (FA) than the PV and comparison groups in a cluster of predominantly limbic and corpus callosal pathways. Segmented tractography indicated the CM group had higher FA in right uncinate fasciculus compared to both groups. They also had smaller right anterior thalamic radiation (ATR) tract volume than the comparison group and higher left ATR FA than the PV group, with these metrics associated with higher emotional abuse and enhanced affective ToM within the CM group, respectively. The PV group had lower inferior fronto-occipital fasciculus FA than the other two groups, which was related to lower affective ToM within the PV group. CONCLUSION: Findings suggest that exposure to early-life stress from caregivers and peers are differentially associated with alterations of neural pathways connecting the frontal, temporal and occipital cortices involved in cognitive and affective control, with possible links to their atypical social cognition.
Subject(s)
Child Abuse , White Matter , Adolescent , Humans , Male , Young Adult , Adult , Child , Social Cognition , Diffusion Tensor Imaging , Brain/diagnostic imaging , White Matter/diagnostic imaging , AnisotropyABSTRACT
BACKGROUND: Early-life interpersonal stress, particularly childhood maltreatment, is associated with neurobiological abnormalities. However, few studies have investigated the neural effects of peer victimisation. AIMS: This study examines common and specific associations between childhood maltreatment, peer victimisation and brain structural alterations in youths. METHOD: Grey matter volume (GMV) and cortical thickness data were collected from 105 age- and gender-matched youths (age range: 17-21 years). Region-of-interest and whole-brain analyses were conducted. RESULTS: For the region-of-interest analyses, the childhood maltreatment group had smaller GMV than controls in left inferior frontal gyrus, bilateral anterior insula, postcentral and lingual regions, which were associated with greater emotional abuse, along with smaller insular GMV than the peer victimisation group, who had smaller left lingual and postcentral GMV than controls. At the whole-brain level, both childhood maltreatment and peer victimisation groups had smaller GMV than controls in a cluster comprising left post/precentral, inferior frontal gyrus, insula, superior parietal and supramarginal gyri. The peer victimisation group alone had increased cortical thickness in a cluster comprising left superior frontal, anterior cingulate and medial orbitofrontal gyri, which was related to greater cyberbullying. CONCLUSIONS: Early-life interpersonal stress is associated with common structural alterations of the inferior frontal-limbic, sensory and lingual regions involved in cognitive control, emotion and sensory processing. The findings of childhood-maltreatment-related reduced anterior insular GMV and peer-victimisation-related increased cortical thickness in the left medial prefrontal-anterior cingulate cluster underscore the distinctive negative effects of childhood maltreatment and peer victimisation, and suggest that peer victimisation, particularly cyberbullying, could be as detrimental as childhood maltreatment.
ABSTRACT
We conducted the first meta-analysis of whole-brain voxel-based DTI studies in childhood maltreatment to elucidate regions of white matter (WM) microstructure abnormality relative to non-maltreated controls. Fourteen DTI datasets were included, comprising 386 individuals with childhood maltreatment and 612 non-maltreated controls. Anisotropic effect-size signed differential mapping, a voxel-based meta-analytic method, was used to examine regions of altered fractional anisotropy (FA) in maltreated individuals relative to controls. Maltreated individuals had significantly reduced FA in the left anterior thalamic radiation and bilateral fornix, optic radiations, inferior longitudinal fasciculus, and inferior frontal-occipital fasciculus, along with the anterior portions of the corpus callosum. There were no regions with increased FA. Decreased FA in the callosal genu and body remained in subgroup analyses of unmedicated and drug-free participants. Findings suggest that childhood maltreatment is associated with widespread WM microstructural abnormalities particularly evident in the fornix, corpus callosum and optic radiations, where the neural pathways linking fronto-limbic and occipital visual cortices presumably involved in conveying and processing the (aversive) experience may be compromised in this population.
Subject(s)
Diffusion Tensor Imaging , White Matter , Anisotropy , Brain/diagnostic imaging , Humans , Neural Pathways/diagnostic imaging , White Matter/diagnostic imagingABSTRACT
Background: Childhood abuse is associated with structural brain abnormalities. Few studies have investigated white matter tract abnormalities in medication-naive, drug-free individuals who experienced childhood abuse. We examined the association between childhood abuse and abnormalities in white matter tracts in that population, controlling for psychiatric comorbidities. Methods: We collected diffusion tensor imaging data for age- and sex-matched youth with childhood abuse, psychiatric controls (matched for psychiatric diagnoses) and healthy controls. Tract-specific analysis was conducted using tractography. Tract-based spatial statistics (TBSS) was used to assess group differences in fractional anisotropy (FA) at the whole-brain level. Results: We included 20 youth who experienced childhood abuse, 18 psychiatric controls and 25 healthy controls in our analysis. Tractography analysis showed abuse-specific reduced tract volume in the inferior longitudinal fasciculus (ILF) and inferior frontal-occipital fasciculus (IFoF) in the abuse group relative to both healthy and psychiatric controls. Furthermore, abnormalities in the left IFoF were associated with greater abuse severity. The TBSS analysis showed significantly reduced FA in a left-hemispheric cluster comprising the ILF, IFoF and corpus callosum splenium in the abuse group relative to healthy and psychiatric controls. Limitations: It is unclear to what extent pubertal development, malnutrition and prenatal drug exposure may have influenced the findings. Conclusion: Childhood abuse is associated with altered structure of neural pathways connecting the frontal, temporal and occipital cortices that are known to mediate affect and cognitive control. The abuse-specific deficits in the ILF and IFoF suggest that fibre tracts presumably involved in conveying and processing the adverse abusive experience are specifically compromised in this population.
Subject(s)
Cerebral Cortex/pathology , Child Abuse , Diffusion Tensor Imaging/methods , Nerve Net/pathology , White Matter/pathology , Adolescent , Cerebral Cortex/diagnostic imaging , Child , Female , Humans , Male , Nerve Net/diagnostic imaging , Neural Pathways/diagnostic imaging , Neural Pathways/pathology , White Matter/diagnostic imagingABSTRACT
AIM: To determine patient/carer expectations of continuous glucose monitoring (CGM) and short-term satisfaction, to assess the efficacy of CGM in improving: fear of hypoglycaemia and glycaemic control (HbA1c , ketosis, hypoglycaemia) and to determine time requirements of diabetes clinic staff in commencing and administering CGM. METHODS: We assessed CGM-naïve patients starting on CGM at a Sydney Diabetes Centre following the introduction of a nationwide government subsidy for CGM. A standardised questionnaire was administered collecting demographic and glycaemic information in addition to Likert scale assessment of expectations and satisfaction. Clinic staff reported time dedicated to CGM education, commencement and follow-up. RESULTS: A total of 55 patients or parents/carers completed baseline questionnaires, with 37 completing a 3-month follow-up questionnaire. There were high expectations of CGM prior to commencement and high satisfaction ratings on follow-up. CGM improved fear of hypoglycaemia, and total daily insulin dose increased after commencement of CGM. There was a trend towards lower HbA1c that was not statistically significant and no statistically significant reduction in ketosis or hypoglycaemia. Comments were mostly positive, with some concern raised regarding technical issues and a lack of subsidy after 21 years of age. Staff time requirements were substantial, with an estimated average of 7.7 h per patient per year. CONCLUSIONS: Patients and families have high expectations of CGM, and satisfaction levels are high in the short term. Total insulin delivery increased after CGM commencement. Time requirements by staff are substantial but are worthwhile if families' overall satisfaction levels are high.
Subject(s)
Blood Glucose Self-Monitoring , Diabetes Mellitus, Type 1 , Government Programs , Adolescent , Ambulatory Care , Child , Fear , Female , Humans , Hypoglycemia/psychology , Insulin Infusion Systems , Male , New South Wales , Patient Satisfaction , Surveys and Questionnaires , Young AdultABSTRACT
Childhood maltreatment is associated with error hypersensitivity. We examined the effect of childhood abuse and abuse-by-gene (5-HTTLPR, MAOA) interaction on functional brain connectivity during error processing in medication/drug-free adolescents. Functional connectivity was compared, using generalized psychophysiological interaction (gPPI) analysis of functional magnetic resonance imaging (fMRI) data, between 22 age- and gender-matched medication-naïve and substance abuse-free adolescents exposed to severe childhood abuse and 27 healthy controls, while they performed an individually adjusted tracking stop-signal task, designed to elicit 50% inhibition failures. During inhibition failures, abused participants relative to healthy controls exhibited reduced connectivity between right and left putamen, bilateral caudate and anterior cingulate cortex (ACC), and between right supplementary motor area (SMA) and right inferior and dorsolateral prefrontal cortex. Abuse-related connectivity abnormalities were associated with longer abuse duration. No group differences in connectivity were observed for successful inhibition. The findings suggest that childhood abuse is associated with decreased functional connectivity in fronto-cingulo-striatal networks during error processing. Furthermore that the severity of connectivity abnormalities increases with abuse duration. Reduced connectivity of error detection networks in maltreated individuals may be linked to constant monitoring of errors in order to avoid mistakes which, in abusive contexts, are often associated with harsh punishment.
ABSTRACT
Childhood maltreatment is associated with attention deficits. We examined the effect of childhood abuse and abuse-by-gene (5-HTTLPR, MAOA, FKBP5) interaction on functional brain connectivity during sustained attention in medication/drug-free adolescents. Functional connectivity was compared, using generalised psychophysiological interaction (gPPI) analysis of functional magnetic resonance imaging (fMRI) data, between 21 age-and gender-matched adolescents exposed to severe childhood abuse and 27 healthy controls, while they performed a parametrically modulated vigilance task requiring target detection with a progressively increasing load of sustained attention. Behaviourally, participants exposed to childhood abuse had increased omission errors compared to healthy controls. During the most challenging attention condition abused participants relative to controls exhibited reduced connectivity, with a left-hemispheric bias, in typical fronto-parietal attention networks, including dorsolateral, rostromedial and inferior prefrontal and inferior parietal regions. Abuse-related connectivity abnormalities were exacerbated in individuals homozygous for the risky C-allele of the single nucleotide polymorphism rs3800373 of the FK506 Binding Protein 5 (FKBP5) gene. Findings suggest that childhood abuse is associated with decreased functional connectivity in fronto-parietal attention networks and that the FKBP5 genotype moderates neurobiological vulnerability to abuse. These findings represent a first step towards the delineation of abuse-related neurofunctional connectivity abnormalities, which hopefully will facilitate the development of specific treatment strategies for victims of childhood maltreatment.
Subject(s)
Brain Mapping , Child Abuse , Parietal Lobe/physiopathology , Adolescent , Adult , Case-Control Studies , Child , Female , Humans , Magnetic Resonance Imaging , Male , Polymorphism, Single Nucleotide , Young AdultABSTRACT
Childhood maltreatment is associated with adverse affective and cognitive consequences including impaired emotion processing, inhibition and attention. However, the majority of functional magnetic resonance imaging (fMRI) studies in childhood maltreatment have examined emotion processing, while very few studies have tested the neurofunctional substrates of cognitive functions and none of attention. This study investigated the association between severe childhood abuse and fMRI brain activation during a parametric sustained attention task with a progressively increasing load of sustained attention in 21 medication-naïve, drug-free young people with a history of childhood abuse controlling for psychiatric comorbidities by including 19 psychiatric controls matched for psychiatric diagnoses, and 27 healthy controls. Behaviorally, the participants exposed to childhood abuse showed increased omission errors in the task which correlated positively trend-wise with the duration of their abuse. Neurofunctionally, the participants with a history of childhood abuse, but not the psychiatric controls, displayed significantly reduced activation relative to the healthy controls during the most challenging attention condition only in typical attention regions including left inferior and dorsolateral prefrontal cortex, insula and temporal areas. We therefore show for the first time that severe childhood abuse is associated with neurofunctional abnormalities in key ventral frontal-temporal sustained attention regions. The findings represent a first step towards the delineation of abuse-related neurofunctional abnormalities in sustained attention, which may help in the development of effective treatments for victims of childhood abuse.
Subject(s)
Attention/physiology , Brain/physiology , Child Abuse , Adolescent , Adult , Brain/physiopathology , Brain Mapping , Child Abuse/psychology , Female , Humans , Magnetic Resonance Imaging , Male , Mental Disorders/physiopathology , Mental Disorders/psychology , Task Performance and Analysis , Young AdultABSTRACT
OBJECTIVE: Childhood maltreatment is associated with various cognitive deficits, including inhibitory deficits and hypersensitivity to negative feedback. The authors used a stop-signal task to investigate the association between severe childhood abuse and inhibitory and error processing brain activation in medication-naive, drug-free young people with and without severe childhood abuse, controlling for psychiatric comorbidities by including a psychiatric control group. METHOD: Using functional MRI, the authors compared brain activation in 22 age- and gender-matched young people exposed to severe childhood abuse, 17 psychiatric comparison subjects matched for psychiatric diagnoses with the abused group, and 27 healthy comparison subjects during an individually adjusted tracking stop-signal task designed to elicit 50% inhibition failures. RESULTS: During failed inhibition, the childhood abuse group showed increased brain activation relative to the healthy comparison group in typical error processing regions of the dorsomedial frontal cortex, including the left and right presupplementary and supplementary motor area and anterior cingulate cortex. The increased activation in a smaller cluster in the supplementary motor area survived comparison with the psychiatric comparison group. No group differences in activation were observed for successful inhibition. CONCLUSIONS: The findings suggest that severe childhood abuse is associated with abnormally increased activation in classical dorsomedial frontal error-processing regions; furthermore, the increased activation in the supplementary motor area was abuse specific. However, childhood abuse was not associated with inhibitory dysfunction. Increased sensitivity of error-detection networks in participants in the childhood abuse group may be due to the constant need to monitor their own actions in order to avoid painful mistakes, which are often associated with harsh punishment in abusive settings.
Subject(s)
Adult Survivors of Child Abuse , Brain/physiopathology , Child Abuse , Adolescent , Case-Control Studies , Child Abuse/psychology , Female , Functional Neuroimaging , Humans , Inhibition, Psychological , Magnetic Resonance Imaging , Male , Psychomotor Performance/physiology , Reaction Time/physiology , Young AdultABSTRACT
OBJECTIVE: Childhood maltreatment acts as a severe stressor that produces a cascade of physiological and neurobiological changes that lead to enduring alterations in brain structure. However, structural neuroimaging findings have been inconsistent. The authors conducted a meta-analysis of published whole-brain voxel-based morphometry studies in childhood maltreatment to elucidate the most robust volumetric gray matter abnormalities relative to comparison subjects to date. METHOD: Twelve data sets were included, comprising 331 individuals (56 children/adolescents and 275 adults) with a history of childhood maltreatment and 362 comparison subjects (56 children/adolescents and 306 adults). Anisotropic effect size-signed differential mapping, a voxel-based meta-analytic method, was used to examine regions of smaller and larger gray matter volumes in maltreated individuals relative to comparison subjects. RESULTS: Relative to comparison subjects, individuals exposed to childhood maltreatment exhibited significantly smaller gray matter volumes in the right orbitofrontal/superior temporal gyrus extending to the amygdala, insula, and parahippocampal and middle temporal gyri and in the left inferior frontal and postcentral gyri. They had larger gray matter volumes in the right superior frontal and left middle occipital gyri. Deficits in the right orbitofrontal-temporal-limbic and left inferior frontal regions remained in a subgroup analysis of unmedicated participants. Abnormalities in the left postcentral and middle occipital gyri were found only in older maltreated individuals relative to age-matched comparison subjects. CONCLUSIONS: The findings demonstrate that the most consistent gray matter abnormalities in individuals exposed to childhood maltreatment are in relatively late-developing ventrolateral prefrontal-limbic-temporal regions that are known to mediate late-developing functions of affect and cognitive control, which are typically compromised in this population.
Subject(s)
Adult Survivors of Child Abuse , Child Abuse , Nerve Fibers, Unmyelinated/pathology , Adolescent , Adult , Adult Survivors of Child Abuse/psychology , Anisotropy , Brain/pathology , Case-Control Studies , Child , Child Abuse/psychology , Female , Humans , Male , Neuroimaging , Young AdultABSTRACT
Functional inhibitory neural networks mature progressively with age. However, nothing is known about the impact of gender on their development. This study employed functional magnetic resonance imaging (fMRI) to investigate the effects of age, sex, and sex by age interactions on the brain activation of 63 healthy males and females, between 13 and 38 years, performing a Stop task. Increasing age was associated with progressively increased activation in typical response inhibition areas of right inferior and dorsolateral prefrontal and temporo-parietal regions. Females showed significantly enhanced activation in left inferior and superior frontal and striatal regions relative to males, while males showed increased activation relative to females in right inferior and superior parietal areas. Importantly, left frontal and striatal areas that showed increased activation in females, also showed significantly increased functional maturation in females relative to males, while the right inferior parietal activation that was increased in males showed significantly increased functional maturation relative to females. The findings demonstrate for the first time that sex-dimorphic activation patterns of enhanced left fronto-striatal activation in females and enhanced right parietal activation in males during motor inhibition appear to be the result of underlying gender differences in the functional maturation of these brain regions.
Subject(s)
Brain/physiology , Inhibition, Psychological , Sex Characteristics , Adolescent , Adolescent Development , Adult , Age Factors , Brain Mapping , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Young AdultABSTRACT
OBJECTIVE: Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder, but diagnosed by subjective clinical and rating measures. The study's aim was to apply Gaussian process classification (GPC) to grey matter (GM) volumetric data, to assess whether individual ADHD adolescents can be accurately differentiated from healthy controls based on objective, brain structure measures and whether this is disorder-specific relative to autism spectrum disorder (ASD). METHOD: Twenty-nine adolescent ADHD boys and 29 age-matched healthy and 19 boys with ASD were scanned. GPC was applied to make disorder-specific predictions of ADHD diagnostic status based on individual brain structure patterns. In addition, voxel-based morphometry (VBM) analysis tested for traditional univariate group level differences in GM. RESULTS: The pattern of GM correctly classified 75.9% of patients and 82.8% of controls, achieving an overall classification accuracy of 79.3%. Furthermore, classification was disorder-specific relative to ASD. The discriminating GM patterns showed higher classification weights for ADHD in earlier developing ventrolateral/premotor fronto-temporo-limbic and stronger classification weights for healthy controls in later developing dorsolateral fronto-striato-parieto-cerebellar networks. Several regions were also decreased in GM in ADHD relative to healthy controls in the univariate VBM analysis, suggesting they are GM deficit areas. CONCLUSIONS: The study provides evidence that pattern recognition analysis can provide significant individual diagnostic classification of ADHD patients and healthy controls based on distributed GM patterns with 79.3% accuracy and that this is disorder-specific relative to ASD. Findings are a promising first step towards finding an objective differential diagnostic tool based on brain imaging measures to aid with the subjective clinical diagnosis of ADHD.
Subject(s)
Attention Deficit Disorder with Hyperactivity/diagnosis , Autistic Disorder/diagnosis , Magnetic Resonance Imaging/methods , Adolescent , Brain Mapping , Case-Control Studies , Female , Humans , Male , Pattern Recognition, Physiological/physiologyABSTRACT
Studies of the psychological well-being of elderly living alone have yielded inconsistent results. Few investigators have distinguished living alone from loneliness in the same study. Thus, the present study examined the independent and interactive effects of living alone and loneliness on depressive symptoms (GDS score) and quality of life (SF-12 MCS score) in a prospective 2-year follow-up cohort study of 2808 community-dwelling older adults (aged ≥55 years) in Singapore, controlling for baseline covariates. In cross-sectional analysis, loneliness was a more robust predictor of GDS score than living arrangements; living alone, when controlled for loneliness, was not associated with GDS score. GDS score associated with living alone was worse for those who felt lonely than for those who did not feel lonely. Similar patterns of association were found in longitudinal analyses and for SF-12 MCS score, although not all were significant. Thus, though living alone predicted lower psychological well-being, its predictive ability was reduced when loneliness was taken into account and loneliness, a stronger predictor, worsened the psychological effects of living alone.
ABSTRACT
The author first examined the underlying factor structure of the defensive pessimism construct and its relations with achievement motives. The author used a sample of 542 Singaporean undergraduate students and found that defensive pessimism is a 2-factor construct that comprises (a) negative expectation, in which individuals worry about possible pitfalls, and (b) reflectivity, in which individuals put forth efforts to prevent possible pitfalls. Then, the author used a sample of 160 Singaporean undergraduate students for Study 2, which supported the proposed model in which mastery predicted the reflectivity factor of defensive pessimism, competition predicted the negative-expectation factor of defensive pessimism indirectly through the mediation of fear of shame, and negative-expectation factor predicted the reflectivity factor of defensive pessimism because, for the defensive pessimists, the act of worrying helps them to respond to their anxiety by initiating the planning process to direct efforts to prevent potential disasters.
Subject(s)
Achievement , Defense Mechanisms , Motivation , Personality Inventory/statistics & numerical data , Set, Psychology , Adolescent , Factor Analysis, Statistical , Female , Humans , Male , Psychometrics/statistics & numerical data , Sex Factors , Singapore , Students/psychology , Young AdultABSTRACT
Youth violence involvement has always been the focus of significant research attention. However, as most of the studies on youth violence have been conducted in Western cultures, little is known about the antecedents of violence in the Asian context. Researchers have suggested that collectivism might be the reason for the lower violent crime rates in Asia. Nevertheless, the present study proposes an alternative approach to the collectivistic orientation and violence relationship: The possibility that allocentrism (collectivist tendency at the individual difference level) might shape the meaning of and the attitudes towards violence; thus not all aspects of a collectivist culture serve as deterrents for violence. Instead of viewing it as a random individual act, violence in a collective cultural context could be seen, under certain circumstances, as a social obligation to one's in-group (especially when one's in-group is supportive of violence) and as an internalization of the norms and values of the culture. Thus, the present study investigates the relationship between allocentrism and its relation to violence in a highly collectivist Asian culture, Singapore. We further hypothesized that collective self-esteem might serve as the mediator between allocentrism and the values of violence. Using a sample of 149 incarcerated Singaporean male adolescents, results support the proposed theoretical model whereby collective self-esteem was found to mediate between allocentrism and the culture's norms and attitudes of violence, which eventually lead to physical violence behaviours.
Subject(s)
Cross-Cultural Comparison , Individuality , Self Concept , Social Identification , Social Values , Violence/psychology , Adolescent , Attitude , Humans , Internal-External Control , Juvenile Delinquency/psychology , Male , Prisoners/psychology , Psychometrics , Singapore , Social Justice , Surveys and Questionnaires , Young AdultABSTRACT
The collectivist preference for nonconfrontational conflict styles is usually attributed to the influences of the Confucian value of harmony, which promotes tolerance of interpersonal transgression. Harmony has two distinct motives in collectivistic Asian societies (Leung, 1997 ): harmony enhancement is affective in nature and represents a genuine concern for relationship harmony, while disintegration avoidance is instrumental in nature and sees harmony maintenance as a means to other ends. Hence, as predicted, harmony enhancement is positively related to the use of integrating and compromising, while disintegration avoidance is positively related to the use of avoiding and obliging and is negatively related to the use of integrating during a conflict with a peer in a collectivistic society, Singapore. Besides examining this from a motivational perspective, the study also examines the role of implicit beliefs of personality on one's choice of conflict styles. The two implicit theories of personality refer to the two different assumptions the lay person has about the mutability of personal attributes; an entity theorist believes that personal attributes are fixed and nonmalleable qualities, while an incremental theorist sees personal attributes as qualities that can be developed and changed. Results reveal that incrementalist implicit beliefs also significantly predicted the use of integrating. Harmony enhancement represents a genuine concern for relationship harmony and involves feelings of closeness, unity, and trust. The finding that integrating is predicted by a harmony enhancement motivation suggests the importance of fostering collectivist values of interdependence and feelings of unity and trust so as to encourage the use of integrating to discuss the opposing views openly and constructively. The present study also underscores the benefit of learning an incremental theory to be open to the positive changes in others and work toward improving the relationship and the situation during a conflict.