Hippocampal and amygdala volumes in adults with posttraumatic stress disorder secondary to childhood abuse or maltreatment: A systematic review

Sex differences in trauma exposure and PTSD symptomatology among refugees, internally displaced people, and asylum seekers: A systematic literature review

This systematic review aimed to explore sex differences in exposure to traumatic events and posttraumatic stress disorder (PTSD) symptomatology among refugees, internally displaced persons (IDPs), and asylum seekers. A comprehensive search was conducted across three databases (PubMed, PsychInfo, and Embase), which yielded 2,255 studies. A total of 15 studies were included for trauma exposure assessment, and 8 studies for PTSD symptomatology assessment. The review revealed significant sex differences in trauma exposure, with women experiencing higher rates of sexual violence, while men faced greater risks of imprisonment and torture. In terms of PTSD symptomatology, our findings showed that women tend to exhibit greater symptoms of arousal and specific symptoms of avoidance such as loss of interest and avoidance of activities reminding of trauma, while men were more likely to experience estrangement and detachment. Findings regarding symptoms of reexperiencing were not entirely consistent. This review emphasizes the importance of considering sex-specific symptoms in trauma assessment among displaced populations and advocates for further research into targeted interventions, especially regarding sexual violence.

Relationships between serotonin 1A receptor DNA methylation, self-reported history of childhood abuse and gray matter volume in major depression

BACKGROUND

Early life adversity is a risk factor for psychopathology and is associated with epigenetic alterations in the 5-HT1A receptor gene promoter. The 5-HT1A receptor mediates neurotrophic effects, which could affect brain structure and function. We examined relationships between self-reported early childhood abuse, 5-HT1A receptor promoter DNA methylation, and gray matter volume (GMV) in Major Depressive Disorder (MDD).

METHODS

Peripheral DNA methylation of 5-HT1A receptor promoter CpG sites -681 and -1007 was assayed in 50 individuals with MDD, including 18 with a history of childhood abuse. T1-weighted structural magnetic resonance imaging (MRI) was performed. Voxel-based morphometry (VBM) was quantified in amygdala, hippocampus, insula, occipital lobe, orbitofrontal cortex, temporal lobe, parietal lobe, and at the voxel level.

RESULTS

No relationship was observed between DNA methylation and history of childhood abuse. We observed regional heterogeneity comparing -681 CpG site methylation and GMV (p = 0.014), with a positive relationship to GMV in orbitofrontal cortex (p = 0.035). Childhood abuse history was associated with higher GMV considering all ROIs simultaneously (p < 0.01). In whole-brain analyses, childhood abuse history was positively correlated with GMV in multiple clusters, including insula and orbitofrontal cortex (pFWE = 0.005), and negatively in intracalcarine cortex (pFWE = 0.001).

LIMITATIONS

Small sample size, childhood trauma assessment instrument used, and assay of peripheral, rather than CNS, methylation.

CONCLUSIONS

These cross-sectional findings support hypotheses of 5-HT1A receptor-related neurotrophic effects, and of increased regional GMV as a potential regulatory mechanism in the setting of childhood abuse. Orbitofrontal cortex was uniquely associated with both childhood abuse history and 5-HT1A receptor methylation.

Frontal cortical volume deficits as enduring evidence of childhood abuse in community adults with AUD and HIV infection comorbidity

Background

Childhood abuse is an underappreciated source of stress, associated with adverse mental and physical health consequences. Childhood abuse has been directly associated with risky behavior thereby increasing the likelihood of alcohol misuse and risk of HIV infection, conditions associated with brain structural and functional deficits. Here, we examined the neural and behavioral correlates of childhood trauma history in alcohol use disorder (AUD), HIV infection (HIV), and their comorbidity (AUD+HIV).

Methods

Occurrence of childhood trauma was evaluated by retrospective interview. Cortical (frontal, temporal, parietal, and occipital), subcortical (hippocampus, amygdala), and regional frontal volumes were derived from structural MRI, adjusted for intracranial volume and age. Test scores of executive functioning, attention/working memory, verbal/visual learning, verbal/visual memory, and motor speed functional domains were standardized on age and education of a laboratory control group.

Results

History of childhood abuse was associated with smaller frontal lobe volumes regardless of diagnosis. For frontal subregional volumes, history of childhood abuse was selectively associated with smaller orbitofrontal and supplementary motor volumes. In participants with a child abuse history, poorer verbal/visual memory performance was associated with smaller orbitofrontal and frontal middle volumes, whereas in those without childhood abuse, poorer verbal/visual memory performance was associated with smaller orbitofrontal, frontal superior, and supplemental motor volumes.

Conclusions

Taken together, these results comport with and extend the findings that childhood abuse is associated with brain and behavioral sequelae in AUD, HIV, and AUD+HIV comorbidity. Further, these findings suggest that sequelae of abuse in childhood may be best conceptualized as a spectrum disorder as significant deficits may be present in those who may not meet criteria for a formal trauma-related diagnosis yet may be suffering enduring stress effects on brain structural and functional health.

Childhood adversity severity modulates the associations between adaptive psychological changes and amygdala volumetric changes in response to behavioral interventions

Background

Adverse Childhood Experience (ACE) has been shown to have detrimental impact on amygdala structure. Prior research found that adaptive psychological changes after Mindfulness-Based Interventions (MBI) were associated with amygdala volumetric changes. The present study aims to further investigate whether such effects also occur among ACE survivors and whether the effects are unique to MBI.

Methods

A total of 64 young adult childhood adversity survivors were randomized to an eight-week MBI or Stress Management Education (SME) as an active control condition. Anatomical MRI and questionnaires on mindfulness, stress and psychological health were collected at baseline and post-intervention. Due to subject dropout, the final sample included 39 subjects (MBI:20, SME:19).

Results

Both groups showed increased mindfulness levels, reduced stress, and improved psychological symptoms (depression, anxiety, and somatization), with no significant group by time interaction effect. There was no significant group difference on amygdala volumetric changes. Within the MBI group, childhood maltreatment severity was a significant mediator between changes of mindfulness levels and right amygdala volumetric changes. Across pooled sample of both groups, childhood maltreatment was a significant moderator for the effect of trait anxiety level changes on left amygdala volumetric changes.

Limitations

Modest sample size, relatively low retention rates, suboptimal monitoring of home practice.

Conclusions

MBI did not demonstrate overall better clinical effects than SME. Psychological-change-dependent amygdala volumetric change was not specific to MBI. Childhood maltreatment severity modulated the relationships between adaptive psychological changes and amygdala volumetric changes.

[Relation between adverse childhood experiences and problematic alcohol consumption in adulthood]

Alcohol use disorder and its consequences are a major public health problem not only worldwide, but in Hungary as well. The problem is aggravated by the low rate of admission to treatment, and by the high dropout rate of the treatment prior to its completion date. The relapse rate is also high, up to more than half of the patients are not able to maintain their abstinence following the first few months after their treatment. Although most patients enrolling in the addiction care system are over the age of 35, the causes of alcohol use disorder often stem from early childhood experiences. Long-term traumas in early childhood are significantly associated with somatic and mental health problems later in life such as substance use, including alcohol dependence. The article begins with reviewing the prevalence of alcohol dependence and defining childhood maltreatment and adverse childhood experiences, then discusses the effects and mechanisms of adverse childhood experiences in light of the development of alcohol use disorders in adults and their low treatment rates. The article also aims to raise awareness of the importance of trauma-focused thinking and trauma-informed approaches in the healthcare system and in planning addiction interventions and services. Orv Hetil. 2023; 164(41): 1628-1636.

Childhood trauma and cortical thickness in healthy women, women with post-traumatic stress disorder, and women with borderline personality disorder

BACKGROUND

Structural brain changes have been associated with childhood trauma (CT) and several trauma-associated mental disorders. It is not known whether specific brain alterations are rather associated with CT as such or with disorders that are common sequelae of CT. In this study, we characterized cortical thickness in three distinct groups with CT: healthy women (HC/CT), women with posttraumatic stress disorder (PTSD/CT) and women with borderline personality disorder (BPD/CT). These three CT-exposed groups were compared with healthy controls not exposed to CT (HC).

METHODS

We recruited 129 women (n = 70 HC, n = 25 HC/CT, n = 14 PTSD/CT, and n = 20 BPD/CT) and acquired T1-weighted anatomical images. FreeSurfer was used for conducting whole-brain cortical thickness between-group comparisons, applying separate generalized linear models to compare cortical thickness of each CT-exposed group with HC.

RESULTS

The HC/CT group had lower cortical thickness in occipital lobe areas (right lingual gyrus, left lateral occipital lobe) than the HC group. The BPD/CT group showed a broader pattern of reduced cortical thickness compared to the HC group, including the bilateral superior frontal gyrus, and bilateral isthmus, the right posterior, and left caudal anterior of the cingulate cortex as well as the right lingual gyrus of the occipital lobe. We found no differences between PTSD/CT and HC.

CONCLUSIONS

Cortical thickness reduction in the right lingual gyrus of the occipital lobe seem to be related to CT but is also present in BPD patients even after adjusting for severity of CT. Possibly, reduced cortical thickness in the lingual gyrus presents a CT-related vulnerability factor for CT-related adult psychopathologies such as BPD. Reduced cortical thickness in the frontal and cingulate cortex may represent unique neuroanatomical markers of BPD possibly related to difficulties in emotion regulation.

Regional superficial amygdala resting-state functional connectivity in adults infers childhood maltreatment severity

Background

Childhood maltreatment (CM) is a potential risk factor for some neuropsychiatric disorders in adulthood (e.g. depression and anxiety) and alters trajectories of brain development. Accumulating evidence suggests that functional connectivity of the limbic system, especially the amygdala, is highly associated with childhood maltreatment, although not all studies have found this. These inconsistent results may be due to differential alterations of amygdala resting-state functional connectivity (rsFC) following childhood maltreatment.

Objective

Our aim was to investigate the relationship between the rsFC of amygdala subregions and CM severity, as well as to develop a stable rsFC-based model for inferring the severity of CM.

Methods

In this study, we employed the Childhood Trauma Questionnaire (CTQ) to assess CM severity in each individual. We explored the relationship between the rsFC of amygdala subregions (i.e. centromedial -CMA, basolateral -BLA, superficial-SFA amygdala) and CM experience in a discovery dataset of n = 110 healthy Chinese participants by linear multiple regression analysis. Subsequent dimensional and categorical approach were performed to elucidate the relationship between rsFCs and CM severity and CM subtypes, respectively. A support vector regression model was then conducted to validate the associations between rsFCs and total CTQ scores. Moreover, we also verified the model into another independent replication dataset (n = 38).

Results

Our findings suggested that childhood maltreatment was negatively associated with rsFC between the right superficial amygdala and perigenual anterior cingulate cortex (pgACC)/postcentral gyrus (PCG) but not the other two amygdala subregions. Moreover, SFA-pgACC coupling was more associated with physical neglect whereas the SFA-PCG was more related to emotional neglect. In addition, supervised machine learning confirmed that using these two rsFCs as predictors could stably estimate continuous maltreatment severity in both discovery and replication datasets.

Conclusion

The current study supports that the rsFCs of superficial amygdala are related to childhood maltreatment and which may be a potential biomarker for the effects of childhood maltreatment-related psychiatric disorders (i.e. depression and anxiety).

The effects of sexual abuse on female adolescent brain structures

Objective

Sexual abuse (SA) is known for its effects on brain structures in adolescents. We aimed to explore if SA has any effect on limbic and prefrontal cortex (PFC) structures. We hypothesized that children with SA would have a thinner PFC with larger amygdala and hippocampus that lead to aberrations in threat detection, orientation and response circuit; that would be highly adaptive in a dangerous environment in the short term.

Method

We included 57 SA and 33 healthy control (HC) female participants. In addition to psychiatric evaluation, we acquired 3 T MR images from all participants. We compared prefrontal cortical thicknesses, hippocampus and amygdala volumes between groups.

Results

The age and education levels of study groups were matched, however, IQ scores and socioeconomic status (SES) scores of the SA group were lower than the controls. Total CTQ scores of the SA group were higher than the HC. Nevertheless, the mean value of sexual abuse scores was above the cut-off scores only for the SA participants. SA participants had larger right and left hippocampus and right amygdala volumes than the controls. SA group had reduced inferior frontal gyrus cortical thickness (T=3.5, p<0.01, cluster size=694 mm2, x=51 y=-30 z=6) than HC group. None of the structural findings were correlated with total or sexual abuse CTQ scores.

Conclusion

Children with SA history has structural abnormalities in threat detection, orientation and response circuit. SA victims with no psychiatric diagnosis have a high probability of psychiatric problems with a possible contribution of these aberrations. SA cases that do not have a diagnosis must not be overlooked as they may have structural changes in emotion related brain regions. Careful follow-up is needed for all of all SA cases.

Psychosocial factors and hippocampal subfields: The Medea-7T study

Specific subfields within the hippocampus have shown vulnerability to chronic stress, highlighting the importance of looking regionally within the hippocampus to understand the role of psychosocial factors in the development of neurodegenerative diseases. A systematic review on psychosocial factors and hippocampal subfield volumes was performed and showed inconsistent results, highlighting the need for future studies to explore this relationship. The current study aimed to explore the association of psychosocial factors with hippocampal (subfield) volumes, using high-field 7T MRI. Data were from the Memory Depression and Aging (Medea)-7T study, which included 333 participants without dementia. Hippocampal subfields were automatically segmented from T2-weighted images using ASHS software. Generalized linear models accounting for correlated outcomes were used to assess the association between subfields (i.e., entorhinal cortex, subiculum, Cornu Ammonis [CA]1, CA2, CA3, dentate gyrus, and tail) and each psychosocial factor (i.e., depressive symptoms, anxiety symptoms, childhood maltreatment, recent stressful life events, and social support), adjusted for age, sex, and intracranial volume. Neither depression nor anxiety was associated with specific hippocampal (subfield) volumes. A trend for lower total hippocampal volume was found in those reporting childhood maltreatment, and a trend for higher total hippocampal volume was found in those who experienced a recent stressful life event. Among subfields, low social support was associated with lower volume in the CA3 (B = -0.43, 95% CI: -0.72; -0.15). This study suggests possible differential effects among hippocampal (subfield) volumes and psychosocial factors.

Deep brain stimulation of the subgenual cingulum and uncinate fasciculus for the treatment of posttraumatic stress disorder

Deep brain stimulation (DBS) has been investigated for neuropsychiatric disorders. In this phase 1 trial, we treated four posttraumatic stress disorder (PTSD) patients with DBS delivered to the subgenual cingulum and the uncinate fasciculus. In addition to validated clinical scales, patients underwent neuroimaging studies and psychophysiological assessments of fear conditioning, extinction, and recall. We show that the procedure is safe and potentially effective (55% reduction in Clinical Administered PTSD Scale scores). Posttreatment imaging data revealed metabolic activity changes in PTSD neurocircuits. During psychophysiological assessments, patients with PTSD had higher skin conductance responses when tested for recall compared to healthy controls. After DBS, this objectively measured variable was significantly reduced. Last, we found that a ratio between recall of extinguished and nonextinguished conditioned responses had a strong correlation with clinical outcome. As this variable was recorded at baseline, it may comprise a potential biomarker of treatment response.

Physical Functional Impairment and the Risk of Incident Mild Cognitive Impairment in an Observational Study of World Trade Center Responders

Background and Objectives

Posttraumatic stress disorder (PTSD) has been linked to increased risk of cognitive dysfunction and physical functional impairment (PFI). The objective of this prospective cohort study was to examine whether PFI was associated with increased risk of incident mild cognitive impairment (MCI) among World Trade Center (WTC) responders with PTSD. We hypothesized that responders with PTSD would have an elevated risk of incident MCI and that PFI would mediate this increase.

Methods

We examined responder participants in the WTC Aging Study whose baseline physical assessments were completed by May 2016-April 2017 and were followed up at least once before December 2019. Those without complete demographic, medical, or behavioral data were excluded. PFI was assessed using measures of upper body strength (maximal handgrip strength [HGS]) and lower extremity physical functioning (Short Physical Performance Battery). PTSD was rated using a diagnostic interview and symptom checklist; MCI and dementia were assessed using the Montreal Cognitive Assessment and diagnosed using the National Institute on Aging-Alzheimer's Association criteria. Group differences and longitudinal comparisons were examined. Cox proportional hazards models were evaluated from time to incident MCI and conversion to dementia. A mediation analysis examined whether PFI mediated associations between PTSD and MCI.

Results

Within the sample of 2,687 WTC responders, 324 (12.06%, 95% CI = [10.83-13.29]) had lower extremity PFI. Responders with lower extremity PFI were older, had lower education and higher body mass, and were at a higher risk of pulmonary embolisms and PTSD. Responders with lower extremity PFI demonstrated lower baseline cognition and had increased hazards of MCI (multivariable-adjusted hazards ratio [aHR] = 1.55 [95% CI 1.21-1.98]); those with MCI converted to dementia more rapidly than those without PFI (2.73 [1.38-5.39] p = 0.004). In addition, each standard deviation decrease in HGS was associated with increased hazards of developing MCI (aHR = 1.35 [95% CI 1.10-1.66]). A mediation model suggested PFI played an intermediary role in the relationship between PTSD and MCI.

Discussion

WTC responders with PFI demonstrated worse cognitive and behavioral outcomes, and PFI played an intermediary role in the relationship between PTSD and incident MCI, suggesting that PFI may be an early indicator of MCI in responders with PTSD. Regular monitoring of PFI should be considered among PTSD populations.

Systems consolidation and fear memory generalisation as a potential target for trauma-related disorders

Fear memory generalisation is a central hallmark in the broad range of anxiety and trauma-related disorders. Recent findings suggest that fear generalisation is closely related to hippocampal dependency during retrieval. In this review, we describe the current understanding about memory generalisation and its potential influence in fear attenuation through pharmacological and behavioural interventions. In light of systems consolidation framework, we propose that keeping memory precision could be a key step to enhance therapeutic outcomes.

Intergenerational transmission of psychological trauma: A structural neuroimaging study

Traumatic events have an important effect in human life and may lead to psychopathological disturbances by affecting the personal and social lives of individuals. Recently, various studies have been reported in the literature showing that the traumatic experiences may be associated with intergenerational psychopathologies. However, there is limited data regarding the neuroimaging studies investigating changes in brain structures in children of traumatized mothers. In this study, we aimed to investigate the potential changes in the hippocampus and amygdala volumes in the children of mothers exposed to mass trauma. The traumatic event experienced by the mothers was the two devastating earthquakes they experienced when they were teenagers. Hippocampus and amygdala volumes were evaluated in magnetic resonance imaging of 40 children whose mothers were exposed to earthquakes and 27 children in control group. Bilateral amygdala volumes were significantly smaller in the children of mothers exposed to earthquake compared to the control group. In addition, right amygdala and hippocampus volumes were smaller in children of mothers exposed to earthquakes than left. This is one of the pioneering neuroimaging studies on the intergenerational transmission of trauma. Our study shows that there may be a potential relationship between intergenerational trauma and various brain structures.

The relationship between chronic PTSD, cortical volumetry and white matter microstructure among Australian combat veterans

BACKGROUND

Posttraumatic stress disorder (PTSD) has been associated with volumetric and white matter microstructural changes among general and veteran populations. However, regions implicated have greatly varied and often conflict between studies, potentially due to confounding comorbidities within samples. This study compared grey matter volume and white matter microstructure among Australian combat veterans with and without a lifetime diagnosis of PTSD, in a homogenous sample assessed for known confounding comorbidities.

METHODS

Sixty-eight male trauma-exposed veterans (16 PTSD-diagnosed; mean age 69 years) completed a battery of psychometric assessments and underwent magnetic resonance and diffusion tensor imaging. Analyses included tract-based spatial statistics, voxel-wise analyses, diffusion connectome-based group-wise analysis, and volumetric analysis.

RESULTS

Significantly smaller grey matter volumes were observed in the left prefrontal cortex (P = 0.026), bilateral middle frontal gyrus (P = 0.021), and left anterior insula (P = 0.048) in the PTSD group compared to controls. Significant negative correlations were found between PTSD symptom severity and fractional anisotropy values in the left corticospinal tract (R² = 0.34, P = 0.024) and left inferior cerebellar peduncle (R² = 0.62, P = 0.016). No connectome-based differences in white matter properties were observed.

CONCLUSIONS

Findings from this study reinforce reports of white matter alterations, as indicated by reduced fractional anisotropy values, in relation to PTSD symptom severity, as well as patterns of reduced volume in the prefrontal cortex. These results contribute to the developing profile of neuroanatomical differences uniquely attributable to veterans who suffer from chronic PTSD.

Inflammation-driven brain and gut barrier dysfunction in stress and mood disorders

Regulation of emotions is generally associated exclusively with the brain. However, there is evidence that peripheral systems are also involved in mood, stress vulnerability vs. resilience, and emotion-related memory encoding. Prevalence of stress and mood disorders such as major depression, bipolar disorder, and post-traumatic stress disorder is increasing in our modern societies. Unfortunately, 30%-50% of individuals respond poorly to currently available treatments highlighting the need to further investigate emotion-related biology to gain mechanistic insights that could lead to innovative therapies. Here, we provide an overview of inflammation-related mechanisms involved in mood regulation and stress responses discovered using animal models. If clinical studies are available, we discuss translational value of these findings including limitations. Neuroimmune mechanisms of depression and maladaptive stress responses have been receiving increasing attention, and thus, the first part is centered on inflammation and dysregulation of brain and circulating cytokines in stress and mood disorders. Next, recent studies supporting a role for inflammation-driven leakiness of the blood-brain and gut barriers in emotion regulation and mood are highlighted. Stress-induced exacerbated inflammation fragilizes these barriers which become hyperpermeable through loss of integrity and altered biology. At the gut level, this could be associated with dysbiosis, an imbalance in microbial communities, and alteration of the gut-brain axis which is central to production of mood-related neurotransmitter serotonin. Novel therapeutic approaches such as anti-inflammatory drugs, the fast-acting antidepressant ketamine, and probiotics could directly act on the mechanisms described here improving mood disorder-associated symptomatology. Discovery of biomarkers has been a challenging quest in psychiatry, and we end by listing promising targets worth further investigation.

Neurobiology of early life adversity: A systematic review of meta-analyses towards an integrative account of its neurobiological trajectories to mental disorders

Adverse childhood experiences (ACEs) may leave long-lasting neurobiological scars, increasing the risk of developing mental disorders in later life. However, no review has comprehensively integrated existing evidence across the fields: hypothalamic-pituitary-adrenal axis, immune/inflammatory system, neuroimaging, and genetics/epigenetics. We thus systematically reviewed previous meta-analyses towards an integrative account of ACE-related neurobiological alterations. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline, a total of 27 meta-analyses until October 2021 were identified. This review found that individuals with ACEs possess blunted cortisol response to psychosocial stressors, low-grade inflammation evinced by increased C-reactive protein levels, exaggerated amygdalar response to emotionally negative information, and diminished hippocampal gray matter volume. Importantly, these alterations were consistently observed in those with and without psychiatric diagnosis. These findings were integrated and discussed in a schematic model of ACE-related neurobiological alterations. Future longitudinal research based on multidisciplinary approach is imperative for ACE-related mental disorders' prevention and treatment.

Differential volume reductions in the subcortical, limbic, and brainstem structures associated with behavior in Prader-Willi syndrome

Individuals with Prader-Willi syndrome (PWS) exhibit complex behavioral characteristics, including hyperphagia, autistic features, and subsequent age-related maladaptive behaviors. While this suggests functional involvements of subcortical, limbic, and brainstem areas, developmental abnormalities in such structures remain to be investigated systematically. Twenty-one Japanese individuals with PWS and 32 healthy controls with typical development were included. T₁-weighted three-dimensional structural magnetic resonance images were analyzed for subcortical, limbic, and brainstem structural volumes, with age as a covariate, using a model-based automatic segmentation tool. Correlations were determined between each volume measurement and behavioral characteristics as indexed by questionnaires and block test scores for hyperphagia (HQ), autistic and obsessional traits, non-verbal intelligence (IQ), and maladaptive behavior (VABS_mal). Compared with the control group, the PWS group showed significantly reduced relative volume ratios per total intracranial volume (TIV) in thalamus, amygdala, and brainstem structures, along with TIV and native volumes in all substructures. While the brainstem volume ratio was significantly lower in all age ranges, amygdala volume ratios were significantly lower during early adulthood and negatively correlated to HQ and VABS_mal but positively correlated to Kohs IQ. Thus, limbic and brainstem volume alterations and differential volume trajectories may contribute to the developmental and behavioral pathophysiology of PWS.

Neuronal Circuits Associated with Fear Memory: Potential Therapeutic Targets for Posttraumatic Stress Disorder

Posttraumatic stress disorder (PTSD) is a psychiatric disorder that is associated with long-lasting memories of traumatic experiences. Extinction and discrimination of fear memory have become therapeutic targets for PTSD. Newly developed optogenetics and advanced in vivo imaging techniques have provided unprecedented spatiotemporal tools to characterize the activity, connectivity, and functionality of specific cell types in complicated neuronal circuits. The use of such tools has offered mechanistic insights into the exquisite organization of the circuitry underlying the extinction and discrimination of fear memory. This review focuses on the acquisition of more detailed, comprehensive, and integrated neural circuits to understand how the brain regulates the extinction and discrimination of fear memory. A future challenge is to translate these researches into effective therapeutic treatment for PTSD from the perspective of precise regulation of the neural circuits associated with the extinction and discrimination of fear memories.

Topography of hippocampal connectivity with sensorimotor cortex revealed by optimizing smoothing kernel and voxel size

Studies of the hippocampus use smaller voxel sizes and smoothing kernels than cortical activation studies, typically using a multivoxel seed with specified radius for connectivity analysis. This study identified optimal processing parameters for evaluating hippocampal connectivity with sensorimotor cortex (SMC), comparing effectiveness by varying parameters during both activation and connectivity analysis. Using both 3mm and 4mm isovoxels, smoothing kernels of 0-10mm were evaluated on the amplitude and extent of motor activation and hippocampal connectivity with SMC. Psychophysiological interactions (PPI) identified hippocampal connectivity with SMC during volitional movements, and connectivity effects from multivoxel seeds were compared with alternate methods; a structural seed represented the mean connectivity map from all voxels within a region, whereas a functional seed represented the regional voxel with maximal SMC connectivity. With few exceptions, the same parameters were optimal for activation and connectivity. Larger isovoxels showed larger activation volumes in both SMC and the hippocampus; connectivity volumes from structural seeds were also larger, except from the posterior hippocampus. Regardless of voxel size, the 10mm smoothing kernel generated larger activation and connectivity volumes from structural seeds, as well as larger beta estimates at connectivity maxima; structural seeds also produced larger connectivity volumes than multivoxel seeds. Functional seeds showed lesser effects from voxel size and smoothing kernels. Optimal parameters revealed topography in structural seed connectivity along both the longitudinal axis and mediolateral axis of the hippocampus. These results indicate larger voxels and smoothing kernels can improve sensitivity for detecting both cortical activation and hippocampal connectivity.

Mechanism of Chronic Stress-Induced Glutamatergic Neuronal Damage in the Basolateral Amygdaloid Nucleus

Stress is a ubiquitous part of our life, while appropriate stress levels can help improve the body's adaptability to the environment. However, sustained and excessive levels of stress can lead to the occurrence of multiple devastating diseases. As an emotional center, the amygdala plays a key role in the regulation of stress-induced psycho-behavioral disorders. The structural changes in the amygdala have been shown to affect its functional characteristics. The amygdala-related neurotransmitter imbalance is closely related to psychobehavioral abnormalities. However, the mechanism of structural and functional changes of glutamatergic neurons in the amygdala induced by stress has not been fully elucidated. Here, we identified that chronic stress could lead to the degeneration and death of glutamatergic neurons in the lateral amygdaloid nucleus, resulting in neuroendocrine and psychobehavioral disorders. Therefore, our studies further suggest that the Protein Kinase R-like ER Kinase (PERK) pathway may be therapeutically targeted as one of the key mechanisms of stress-induced glutamatergic neuronal degeneration and death in the amygdala.

"Can mental health nurses working in acute mental health units really be trauma-informed?" An integrative review of the literature

WHAT IS KNOWN ON THE SUBJECT?: The lifetime prevalence of trauma for consumers of mental health services is high. Both nurses and consumers of mental health services experience trauma and re-traumatization in mental health units. TIC is a model of care or approach increasingly used in mental health units to guide nursing actions to minimize trauma and re-traumatization for those working and accessing mental health services. WHAT THE PAPER ADDS TO EXISTING KNOWLEDGE?: Overall, there is poor quality of studies exploring TIC in acute mental health units from the perspective of the MHN. Acute mental health units have competing organizational demands that can often be a source of conflict for nurses providing TIC. To be trauma-informed, a critical examination of the dynamic and unique system-related processes in mental health units is required. TIC literature reveals that nurses are seeking to develop the basic skills expected to be gained in earlier preparatory education to respond therapeutically to consumers. Not all MHNs agree that TIC is necessarily a new or useful model to inform their practice. Trauma and re-traumatization experienced by MHNs can be a source of conflict for TIC in the mental health unit environment. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: The broader environmental and organizational demands placed on nurses can create professional and moral conflict for providing TIC. TIC should acknowledge trauma and re-traumatization experienced by MHNs in the acute mental health units.

ABSTRACT

INTRODUCTION: Trauma-informed care (TIC) is an approach that mental health inpatient units are increasingly adopting, with mental health nurses (MHNs) being the largest occupational group working this area.

AIM

To critically examine the literature on TIC in mental health inpatient units from a MHN perspective.

METHODS

Primary studies examining TIC in mental health inpatient units from a MHN perspective were examined in CINAHL, Medline and PsycINFO database including the reference lists of primary sources. A total of n = 10 studies met the inclusion criteria with four themes identified.

DISCUSSION

There is a paucity of quality research available on TIC to guide MHNs employed in mental health inpatient units. The review has highlighted that MHN practice is influenced by the medical model ideology and competing organizational demands that can at least partially negate the effective provision of TIC.

IMPLICATIONS FOR PRACTICE

For purposeful application of TIC, the parallel and often unconscious organizational processes that exist for MHNs working in mental health units must too be examined.

RELEVANCE STATEMENT

The review invites an opportunity for important reflections by MHNs employed in mental health units. TIC may help restore MHN practice to the interpersonal tenants the profession is best distinguished by.

Early-life stress does not alter spatial memory performance, hippocampal neurogenesis, neuroinflammation, or telomere length in 20-month-old male mice

Early-life stress (ES) increases the risk for psychopathology and cognitive decline later in life. Because the neurobiological substrates affected by ES (i.e., cognition, neuroplasticity, and neuroinflammation) are also altered in aging, we set out to investigate if and how ES in the first week of life affects these domains at an advanced age, and how ES modulates the aging trajectory per se. We subjected C57BL/6j mice to an established ES mouse model from postnatal days 2–9. Mice underwent behavioral testing at 19 months of age and were sacrificed at 20 months to investigate their physiology, hippocampal neuroplasticity, neuroinflammation, and telomere length. ES mice, as a group, did not perform differently from controls in the open field or Morris water maze (MWM). Hippocampal neurogenesis and synaptic marker gene expression were not different in ES mice at this age. While we find aging-associated alterations to neuroinflammatory gene expression and telomere length, these were unaffected by ES. When integrating the current data with those from our previously reported 4- and 10-month-old cohorts, we conclude that ES leads to a ‘premature’ shift in the aging trajectory, consisting of early changes that do not further worsen at the advanced age of 20 months. This could be explained e.g. by a ‘floor’ effect in ES-induced impairments, and/or age-induced impairments in control mice. Future studies should help understand how exactly ES affects the overall aging trajectory.

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Early-life stress (ES) exposure does not worsen water maze learning in aged male mice.

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ES does not affect brain plasticity markers at 20 months of age.

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Hippocampal telomere length is reduced by aging but unaffected by ES.

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ES leads to a premature aging trajectory that does not worsen with aging.

Stability of hippocampal subfield volumes after trauma and relationship to development of PTSD symptoms

BACKGROUND

The hippocampus plays a central role in post-traumatic stress disorder (PTSD) pathogenesis, and the majority of neuroimaging research on PTSD has studied the hippocampus in its entirety. Although extensive literature demonstrates changes in hippocampal volume are associated with PTSD, fewer studies have probed the relationship between symptoms and the hippocampus' functionally and structurally distinct subfields. We utilized data from a longitudinal study examining post-trauma outcomes to determine whether hippocampal subfield volumes change post-trauma and whether specific subfields are significantly associated with, or prospectively related to, PTSD symptom severity. As a secondary aim, we leveraged our unique study design sample to also investigate reliability of hippocampal subfield volumes using both cross-sectional and longitudinal pipelines available in FreeSurfer v6.0.

METHODS

Two-hundred and fifteen traumatically injured individuals were recruited from an urban Emergency Department. Two-weeks post-injury, participants underwent two consecutive days of neuroimaging (time 1: T1, and time 2: T2) with magnetic resonance imaging (MRI) and completed self-report assessments. Six-months later (time 3: T3), participants underwent an additional scan and were administered a structured interview assessing PTSD symptoms. First, we calculated reliability of hippocampal measurements at T1 and T2 (automatically segmented with FreeSurfer v6.0). We then examined the prospective (T1 subfields) and cross-sectional (T3 subfields) relationship between volumes and PTSD. Finally, we tested whether change in subfield volumes between T1 and T3 explained PTSD symptom variability.

RESULTS

After controlling for sex, age, and total brain volume, none of the subfield volumes (T1) were prospectively related to T3 PTSD symptoms nor were subfield volumes (T3) associated with current PTSD symptoms (T3). Tl - T2 reliability of all hippocampal subfields ranged from good to excellent (intraclass correlation coefficient (ICC) values > 0.83), with poorer reliability in the hippocampal fissure.

CONCLUSION

Our study was a novel examination of the prospective relationship between hippocampal subfield volumes in relation to PTSD in a large trauma-exposed urban sample. There was no significant relationship between subfield volumes and PTSD symptoms, however, we confirmed FreeSurfer v6.0 hippocampal subfield segmentation is reliable when applied to a traumatically-injured sample, using both cross-sectional and longitudinal analysis pipelines. Although hippocampal subfield volumes may be an important marker of individual variability in PTSD, findings are likely conditional on the timing of the measurements (e.g. acute or chronic post-trauma periods) and analysis strategy (e.g. cross-sectional or prospective).

Subcortical gray matter volumes in asthma: associations with asthma duration, control, and anxiety

Asthma as a chronic inflammatory disease can be expected to affect central nervous system structures but little is known about subcortical structures in asthma and their potential association with illness-specific outcomes and anxiety. A total of 40 young adults (20 with asthma and 20 gender- and age-matched controls) underwent high-resolution T1-weighted MRI scan, viewed short distressing film clips, and filled in questionnaires about anxious and depressed mood, as well as asthma history, control, and catastrophizing thoughts about asthma, for those with asthma. The structural scans were processed in FSL's FIRST program to delineate subcortical structures of interest: amygdala, hippocampus, putamen, pallidum, caudate nucleus, nucleus accumbens, and thalamus. Findings showed no general reduction in subcortical gray matter volumes in asthma compared to controls. Asthma duration, asthma control, and catastrophizing of asthma and asthma attacks were negatively associated with volumes of putamen and pallidum, and to a weaker extent thalamus and amygdala, while controlling for gender, age, and corticosteroid inhaler use. In addition, stronger anxiety in response to distressing films was associated with lower volume of the pallidum, whereas general anxious and depressed mood was unrelated to subcortical structures. Thus, although there are no subcortical structural differences between young adults with asthma and healthy controls, longer asthma history, suboptimal management, and illness-related anxiety are reflected in lower gray matter volumes of subcortical structures, further emphasizing the importance of maintaining optimal asthma control.

Association between childhood trauma and brain anatomy in women with post-traumatic stress disorder, women with borderline personality disorder, and healthy women

BACKGROUND

Childhood trauma (CT) is associated with altered brain anatomy. These neuroanatomical changes might be more pronounced in individuals with a psychiatric disorder. Post-traumatic stress disorder (PTSD) and borderline personality disorder (BPD) are more prevalent in individuals with a history of CT.

OBJECTIVE

In this study, we examined limbic and total brain volumes in healthy women with and without a history of CT and in females with PTSD or BPD and a history of CT to see whether neuroanatomical changes are a function of psychopathology or CT.

METHOD

In total, 128 women (N = 70 healthy controls without CT, N = 25 healthy controls with CT, N = 14 individuals with PTSD, and N = 19 individuals with BPD) were recruited. A T1-weighted anatomical MRI was acquired from all participants for Freesurfer-based assessment of total brain, hippocampus, and amygdala volumes. Severity of CT was assessed with a clinical interview and the Childhood Trauma Questionnaire. Group differences in hippocampal and amygdala volumes (adjusted for total brain volume) and total brain volume (adjusted for height) were characterized by analysis of covariance.

RESULTS

Volume of the total brain, hippocampus, and amygdala did not differ between the four groups (p > .05). CT severity correlated negatively with total brain volume across groups (r = -0.20; p = .029).

CONCLUSIONS

CT was associated with reduced brain volume but PTSD or BPD was not. The association between CT and reduced brain volume as a global measure of brain integrity suggests a common origin for vulnerability to psychiatric disorders later in life.

Traces of Trauma: A Multivariate Pattern Analysis of Childhood Trauma, Brain Structure, and Clinical Phenotypes

BACKGROUND

Childhood trauma (CT) is a major yet elusive psychiatric risk factor, whose multidimensional conceptualization and heterogeneous effects on brain morphology might demand advanced mathematical modeling. Therefore, we present an unsupervised machine learning approach to characterize the clinical and neuroanatomical complexity of CT in a larger, transdiagnostic context.

METHODS

We used a multicenter European cohort of 1076 female and male individuals (discovery: n = 649; replication: n = 427) comprising young, minimally medicated patients with clinical high-risk states for psychosis; patients with recent-onset depression or psychosis; and healthy volunteers. We employed multivariate sparse partial least squares analysis to detect parsimonious associations between combinations of items from the Childhood Trauma Questionnaire and gray matter volume and tested their generalizability via nested cross-validation as well as via external validation. We investigated the associations of these CT signatures with state (functioning, depressivity, quality of life), trait (personality), and sociodemographic levels.

RESULTS

We discovered signatures of age-dependent sexual abuse and sex-dependent physical and sexual abuse, as well as emotional trauma, which projected onto gray matter volume patterns in prefronto-cerebellar, limbic, and sensory networks. These signatures were associated with predominantly impaired clinical state- and trait-level phenotypes, while pointing toward an interaction between sexual abuse, age, urbanicity, and education. We validated the clinical profiles for all three CT signatures in the replication sample.

CONCLUSIONS

Our results suggest distinct multilayered associations between partially age- and sex-dependent patterns of CT, distributed neuroanatomical networks, and clinical profiles. Hence, our study highlights how machine learning approaches can shape future, more fine-grained CT research.

Common and distinct patterns of gray matter alterations in borderline personality disorder and posttraumatic stress disorder: A dual meta-analysis

BACKGROUND

Borderline personality disorder (BPD) and posttraumatic stress disorder (PTSD) are severe psychiatric disorders and often co-occur, either of the two will seriously threaten to public health. However, we lack ample evidences to understand the potential pathophysiologic mechanisms of gray matter (GM) alterations in the two disorders.

METHODS

We performed a meta-analysis in both BPD (15 datasets including 442 BPD subjects versus 441 healthy controls) and PTSD (11 datasets including 214 PTSD subjects versus 258 healthy controls) applying anisotropic effect-size-based algorithms (AES-SDM) method.

RESULTS

Conjunction analysis found relative GM volume reductions in both disorders in the orbitofrontal gyrus and anterior cingulate cortex, contrarily, differences were predominantly observed that GM volume increased in the posterior cingulate gyrus and precuneus in BPD subjects, and GM volume decreased in the amygdala-hippocampal fear circuit, fusiform gyrus in PTSD subjects.

CONCLUSIONS

Group comparisons and conjunction analyses in BPD and PTSD identified same regions of GM volume reductions in the orbitofrontal gyrus and anterior cingulate cortex, which may provide clues for the neurobiological mechanisms and clinical diagnosis underpinning two disorders.

A Systematic Review of Reviews of the Outcome of Noninstitutional Child Maltreatment

The aim of the systematic review described in this article was to synthesize available high-quality evidence on the outcomes of noninstitutional child maltreatment across the life span. A systematic review of previous systematic reviews and meta-analyses was conducted. Ten databases were searched. One hundred eleven papers which met stringent inclusion and exclusion criteria were selected for review. Papers were included if they reported systematic reviews and meta-analyses of longitudinal or cross-sectional controlled studies, or single-group cohort primary studies of the outcomes of child maltreatment in the domains of physical and mental health and psychosocial adjustment of individuals who were children lived mainly with their families. Using AMSTAR criteria, selected systematic reviews and meta-analyses were found to be of moderate or high quality. Searches, study selection, data extraction, and study quality assessments were independently conducted by two researchers, with a high degree of interrater reliability. The 111 systematic reviews and meta-analyses reviewed in this article covered 2,534 independent primary studies involving 30,375,962 participants, of whom more than 518,022 had been maltreated. The magnitude and quality of this evidence base allow considerable confidence to be placed in obtained results. Significant associations were found between a history of child maltreatment and adjustment in the domains of physical health, mental health, and psychosocial adjustment in a very wide range of areas. The many adverse outcomes associated with child maltreatment documented in this review highlight the importance of implementing evidence-based child protection policies and practices to prevent maltreatment and treat child abuse survivors.

Reduced gray matter volume in the left prefrontal, occipital, and temporal regions as predictors for posttraumatic stress disorder: a voxel-based morphometric study

The concept of acute stress disorder (ASD) was introduced as a diagnostic entity to improve the identification of traumatized people who are likely to develop posttraumatic stress disorder (PTSD). Neuroanatomical models suggest that changes in the prefrontal cortex, amygdala, and hippocampus play a role in the development of PTSD. Using voxel-based morphometry, this study aimed to investigate the predictive power of gray matter volume (GMV) alterations for developing PTSD. The GMVs of ASD patients (n = 21) were compared to those of PTSD patients (n = 17) and healthy controls (n = 18) in whole-brain and region-of-interest analyses. The GMV alterations seen in ASD patients shortly after the traumatic event (T1) were also correlated with PTSD symptom severity and symptom clusters 4 weeks later (T2). Compared with healthy controls, the ASD patients had significantly reduced GMV in the left visual cortex shortly after the traumatic event (T1) and in the left occipital and prefrontal regions 4 weeks later (T2); no significant differences in GMV were seen between the ASD and PTSD patients. Furthermore, a significant negative association was found between the GMV reduction in the left lateral temporal regions seen after the traumatic event (T1) and PTSD hyperarousal symptoms 4 weeks later (T2). Neither amygdala nor hippocampus alterations were predictive for the development of PTSD. These data suggest that gray matter deficiencies in the left hemispheric occipital and temporal regions in ASD patients may predict a liability for developing PTSD.

Amygdala Nuclei Volumes Are Selectively Associated With Social Network Size in Homeless and Precariously Housed Persons

Objective: The amygdala is a brain region comprised of a group of functionally distinct nuclei that play a central role in social behavior. In homeless and precariously housed individuals, high rates of multimorbidity, and structural aspects of the environment may dysregulate social functioning. This study examined the neurobiological substrates of social connection in homeless and precariously housed persons by examining associations between amygdala nuclei volumes and social network size. Methods: Sixty participants (mean age 43.6 years; 73.3% male) were enrolled from an ongoing study of homeless and precariously housed adults in Vancouver, Canada. Social network size was assessed using the Arizona Social Support Interview Schedule. Amygdala nuclei volumes were extracted from anatomic T1-weighted MRI data. The central and basolateral amygdala nuclei were selected as they are implicated in anxiety-related and social behaviors. The hippocampus was included as a control brain region. Multivariable regression analysis investigated the relationship between amygdala nuclei volumes and social network size. Results: After controlling for age, sex, and total brain volume, individuals with the larger amygdala and central nucleus volumes had a larger network size. This association was not observed for the basolateral amygdala complex, though subsequent analysis found the basal and accessory basal nuclei of the basolateral amygdala were significantly associated with social network size. No association was found for the lateral amygdala nucleus or hippocampus. Conclusions: These findings suggest that select amygdala nuclei may be differentially involved in the social connections of persons with multimorbid illness and social marginalization.

Effect of Combat Exposure and Posttraumatic Stress Disorder on Telomere Length and Amygdala Volume

BACKGROUND

Traumatic stress can adversely affect physical and mental health through neurobiological stress response systems. We examined the effects of trauma exposure and posttraumatic stress disorder (PTSD) on telomere length, a biomarker of cellular aging, and volume of the amygdala, a key structure of stress regulation, in combat-exposed veterans. In addition, the relationships of psychopathological symptoms and autonomic function with telomere length and amygdala volume were examined.

METHODS

Male combat veterans were categorized as having PTSD diagnosis (n = 102) or no lifetime PTSD diagnosis (n = 111) based on the Clinician-Administered PTSD Scale. Subjects were assessed for stress-related psychopathology, trauma severity, autonomic function, and amygdala volumes by magnetic resonance imaging.

RESULTS

A significant interaction was found between trauma severity and PTSD status for telomere length and amygdala volume after adjusting for multiple confounders. Subjects with PTSD showed shorter telomere length and larger amygdala volume than those without PTSD among veterans exposed to high trauma, while there was no significant group difference in these parameters among those exposed to low trauma. Among veterans exposed to high trauma, greater telomere shortening was significantly correlated with greater norepinephrine, and larger amygdala volume was correlated with more severe psychological symptoms and higher heart rates.

CONCLUSIONS

These data suggest that the intensity of the index trauma event plays an important role in interacting with PTSD symptomatology and autonomic activity in predicting telomere length and amygdala volume. These results highlight the importance of trauma severity and PTSD status in predicting certain biological outcomes.

Adverse childhood experiences and cognitive function among adults with excess adiposity

BACKGROUND

Adverse childhood experiences (ACEs) and obesity are independently associated with brain/neurocognitive health. Despite a growing emphasis on the importance of early life adversity on health, the relationship between ACEs and neurocognition in adults with overweight/obesity is unclear. The objective was to examine associations between self-reported ACEs and measured neurocognitive domains in a sample of adults with overweight/obesity.

METHODS

Participants were 95 predominantly white, highly educated adult women (76% female, 81% Caucasian, and 75% ≥ bachelor's degree) with excess adiposity enrolled in the Cognitive and Self-regulatory Mechanisms of Obesity Study. ACEs and fluid/crystallized neurocognitive domains were measured at baseline using the Adverse Childhood Experiences Scale and the NIH Toolbox Cognition Battery and Automated Neuropsychological Assessment Metric, respectively.

RESULTS

Higher ACEs scores were negatively correlated with fluid cognition (r = -.34, P < .001) but not crystallized cognition (r = .01, ns). Individuals with 3 and 4+ ACEs displayed significantly lower fluid cognition scores than those with fewer ACEs F 4,89 = 3.24, P < .05. After accounting for body mass index (BMI), age, sex, race, and education, higher ACEs scores were still associated with poorer performance on overall fluid cognition (β = -.36, P < .01), along with the following subtests: Stroop Colour/Word test (β = -.23, P < .05), Go/No-Go omissions (β = .29, P < .01), and Picture Sequence Memory task (β = -.30, P < .01).

CONCLUSIONS

The role of ACEs in health may be related to their associations with executive function and episodic neurocognitive domains essential to cognitive processing and self-regulation. Obesity science should further examine the role of ACEs and neurocognition in obesity prevention, prognosis, and treatment using more rigorous, prospective designs and more diverse samples.

Inflammation in Post-Traumatic Stress Disorder (PTSD): A Review of Potential Correlates of PTSD with a Neurological Perspective

Post-traumatic stress disorder (PTSD) is a chronic condition characterized by symptoms of physiological and psychosocial burden. While growing research demonstrated signs of inflammation in PTSD, specific biomarkers that may be representative of PTSD such as the detailed neural correlates underlying the inflammatory responses in relation to trauma exposure are seldom discussed. Here, we review recent studies that explored alterations in key inflammatory markers in PTSD, as well as neuroimaging-based studies that further investigated signs of inflammation within the brain in PTSD, as to provide a comprehensive summary of recent literature with a neurological perspective. A search was conducted on studies published from 2009 through 2019 in PubMed and Web of Science. Fifty original articles were selected. Major findings included elevated levels of serum proinflammatory cytokines in individuals with PTSD across various trauma types, as compared with those without PTSD. Furthermore, neuroimaging-based studies demonstrated that altered inflammatory markers are associated with structural and functional alterations in brain regions that are responsible for the regulation of stress and emotion, including the amygdala, hippocampus, and frontal cortex. Future studies that utilize both central and peripheral inflammatory markers are warranted to elucidate the underlying neurological pathway of the pathophysiology of PTSD.

Atypical lateralization in neurodevelopmental and psychiatric disorders: What is the role of stress?

Hemispheric asymmetries are a major organizational principle of the human brain. In different neurodevelopmental and psychiatric disorders, like schizophrenia, autism spectrum disorders, depression, dyslexia and posttraumatic stress disorder, functional and/or structural hemispheric asymmetries are altered compared to healthy controls. The question, why these disorders all share the common characteristic of altered hemispheric asymmetries despite vastly different etiologies and symptoms remains one of the unsolved mysteries of laterality research. This review is aimed at reviewing potential reasons for why atypical lateralization is so common in many neurodevelopmental and psychiatric disorders. To this end, we review the evidence for overlaps in the genetic and non-genetic factors involved in the ontogenesis of different disorders and hemispheric asymmetries. While there is evidence for genetic overlap between different disorders, only few asymmetry-related loci have also been linked to disorders and importantly, those effects are mostly specific to single disorders. However, there is evidence for shared non-genetic influences between disorders and hemispheric asymmetries. Most neurodevelopmental and psychiatric disorders show alterations in the hypothalamic-pituitary adrenocortical (HPA) axis and maternal as well as early life stress have been implicated in their etiology. Stress has also been suggested to affect hemispheric asymmetries. We propose a model in which early life stress as well as chronic stress not only increases the risk for psychiatric and neurodevelopmental disorders but also changes structural and functional hemispheric asymmetries leading to the aberrant lateralization patterns seen in these disorders. Thus, pathology-related changes in hemispheric asymmetries are not a factor causing disorders, but rather a different phenotype that is affected by partly overlapping ontogenetic factors, primarily stress.

The influence of early postnatal chronic mild stress stimulation on the activation of amygdala in adult rat

Amygdala is a limbic structure involved in the stress response. The immunohistochemical and morphometric methods were used to examine whether the chronic mild psychological stress during the early postnatal period would change activation of amygdaloid nuclei in response to the same stressor in adult. In the study we focused on the role of neurons containing calbindin (CB), calretinin (CR), parvalbumin (PV) and nitric oxide synthase (NOS). The rats were divided into three groups: control non-stressed animals and two experimental: EI consisted of animals that were exposed to acute stress in the high-light, open-field test (HL-OF) at P90 (P - postnatal day) and EII consisted of rats that were exposed to chronic stress in HL-OF, daily during the first 21 postnatal days and then once at P90. The scheme of activation of amygdaloid nuclei under stress in EI and EII group was similar. The highest density of c-Fos-ir cells (c-Fos - a marker of neuronal activation) was demonstrated by the medial nucleus (Me) and bed nucleus of the accessory olfactory tract (BAOT). The amygdaloid nuclei diversity after HL-OF was determined by the high activation of the NOS-ir cells in the Me and NOS- and CR-ir cells in the BAOT. These are probably projection neurons involved in modulation of defensive, reproductive and autonomic behavior in stress response and creation/storage of aversive memory. However, in comparison with EI group, significant decrease in density of c-Fos-ir cells, in almost all amygdaloid nuclei of EII group was revealed. Particularly in BAOT and Me the strong decrease of activity of NOS- and CR-ir neurons was observed. It probably results in attenuation of stress responses what, depending on the circumstances, can be adaptive or maladaptive.

The roles of early-life adversity and rumination in neural response to emotional faces amongst anxious and depressed adults

BACKGROUND

Early-life adversity (ELA) is a risk factor for internalizing psychopathology (IP). ELA is also linked to alterations in neural phenotypes of emotion processing and maladaptive emotion regulatory strategies, such as ruminative brooding, in adulthood. We therefore expected that ELA would predict cortical brain activation to emotional faces in transdiagnostic IP and in turn, mediate the extent of rumination amongst patients with IPs and ELA (IP + ELA).

METHOD

One hundred and thirty-two individuals, including 102 treatment-seeking adults with heterogeneous IPs and 30 healthy controls (HCs) performed an Emotional Face-Matching Task during functional magnetic resonance imaging. Whole-brain analyses compared HC (n = 30), IP (n = 52), and IP + ELA (n = 50) neural responses to emotional (angry, fearful, happy, and sad) faces v. shapes, controlling for depression and anxiety symptoms. Parameter estimates of activation were extracted for significant between-group differences and tested as a mediator of ruminative brooding in IP + ELA.

RESULTS

IP + ELA demonstrated increased activation in the superior frontal gyrus and anterior cingulate cortex (fear), superior parietal lobule, precuneus, posterior cingulate, and inferior temporal gyrus (fear only), and cuneus (fear and angry). These regions were preferentially correlated with ruminative brooding in IP + ELA, many of which mediated the link between IP + ELA and ruminative brooding.

CONCLUSIONS

Results provide evidence that ELA history amongst IP patients augments engagement of brain regions involved in emotion processing, above and beyond what is accounted for by current symptoms. Though longitudinal designs are needed, alterations in the neural correlates of maladaptive processing of socio-emotional information may be a common pathway by which ELA poses risk for psychopathology.

Neurobiological mechanisms underlying sex-related differences in stress-related disorders: Effects of neuroactive steroids on the hippocampus

Men and women differ in their vulnerability to a variety of stress-related illnesses, but the underlying neurobiological mechanisms are not well understood. This is likely due to a comparative dearth of neurobiological studies that assess male and female rodents at the same time, while human neuroimaging studies often don't model sex as a variable of interest. These sex differences are often attributed to the actions of sex hormones, i.e. estrogens, progestogens and androgens. In this review, we summarize the results on sex hormone actions in the hippocampus and seek to bridge the gap between animal models and findings in humans. However, while effects of sex hormones on the hippocampus are largely consistent in animals and humans, methodological differences challenge the comparability of animal and human studies on stress effects. We summarise our current understanding of the neurobiological mechanisms that underlie sex-related differences in behavior and discuss implications for stress-related illnesses.

The amygdala differentially regulates defensive behaviors evoked by CO2

CO₂ inhalation can provoke panic attacks in humans, and the likelihood is increased in patients with panic disorder. Identifying brain sites involved could provide important mechanistic insight into the illness. In mice, the amygdala has been suggested to promote CO₂ responses; however, recent studies in humans with amygdala damage indicate the amygdala is not required for CO₂-induced fear and panic and might actually oppose these responses. To clarify the role of the amygdala, we produced lesions in mice paralleling the human lesions, and characterized behavioral responses to CO₂. Compared to sham controls, we found that amygdala-lesioned mice froze less to 10% CO₂, and unlike shams they also began to jump frenetically. At 20% CO₂, controls also exhibited jumping, suggesting it is a normal response to more extreme CO₂ concentrations. The effect of amygdala lesions was specific to CO₂ as amygdala-lesioned mice did not jump in response to a predator odor or to an auditory conditioned stimulus. In amygdala-lesioned mice, jumping evoked by 10% CO₂ was eliminated by co-lesioning the dorsal periaqueductal gray, a structure implicated in panic and escape-related behaviors. Together, these observations suggest a dual role for the amygdala in the CO₂ response: promoting CO₂-induced freezing, and opposing CO₂-induced jumping, which may help explain the exaggerated CO₂ responses in humans with amygdala lesions.

Pediatric cancer, posttraumatic stress and fear-related neural circuitry

This review examines the neurobiological effects of pediatric cancer-related posttraumatic stress symptoms (PTSS). We first consider studies on prevalence and predictors of childhood cancer-related PTSS and compare these studies to those in typically developing (i.e., noncancer) populations. Then, we briefly introduce the brain regions implicated in PTSS and review neuroimaging studies examining the neural correlates of PTSS in noncancer populations. Next, we present a framework and recommendations for future research. In particular, concurrent evaluation of PTSS and neuroimaging, as well as sociodemographic, medical, family factors, and other life events, are needed to uncover mechanisms leading to cancer-related PTSS. We review findings from neuroimaging studies on childhood cancer and one recent study on cancer-related PTSS as a starting point in this line of research.

Hippocampal subfield volumes and childhood trauma in bipolar disorders

BACKGROUND

Alterations in hippocampal structure and function are present in bipolar disorder (BD). Childhood trauma is associated with risk for BD, and the several subfields of the hippocampus are differentially sensitive to the effects of stressors of the sort associated with risk for BD. The current study therefore sought to test the hypothesis that childhood trauma may be differentially associated with abnormal hippocampal subfield volumes in BD.

METHODS

104 participants with BD type I (BD-I, n = 56) or BD type II (BD-II, n = 48) and 81 healthy controls (HC) underwent high-resolution structural magnetic resonance neuroimaging. Hippocampal subfield volumes were determined using FreeSurfer. Childhood trauma was assessed with the Childhood Trauma Questionnaire (CTQ).

RESULTS

There were significant effects of diagnosis on intracranial volume corrected hippocampal subfield volumes bilaterally as well as a significant interaction between diagnosis and childhood trauma. Hippocampal volumes did not differ between the BD-I and BD-II subgroups but hippocampal volumes were smaller in both groups when compared to HC. There was a significant effect of childhood trauma on bilateral presubiculum volume as well as significant interactions between diagnosis and childhood trauma on bilateral CA1, presubiculum and subiculum volumes, the direction of which differed between individuals with BD (larger) and HC (smaller).

LIMITATIONS

Recall bias may influence the reliability of the retrospective assessment of childhood trauma experiences.

CONCLUSIONS

Childhood trauma demonstrates differential effects on hippocampal subfield volumes of BD and HC, particularly in hippocampal subfields involved in emotion regulation.

Interactive effects of genetic polymorphisms and childhood adversity on brain morphologic changes in depression

The etiology of depression is characterized by the interplay of genetic and environmental factors and brain structural alteration. Childhood adversity is a major contributing factor in the development of depression. Interactions between childhood adversity and candidate genes for depression could affect brain morphology via the modulation of neurotrophic factors, serotonergic neurotransmission, or the hypothalamus-pituitary-adrenal (HPA) axis, and this pathway may explain the subsequent onset of depression. Childhood adversity is associated with structural changes in the hippocampus, amygdala, anterior cingulate cortex (ACC), and prefrontal cortex (PFC), as well as white matter tracts such as the corpus callosum, cingulum, and uncinate fasciculus. Childhood adversity showed an interaction with the brain-derived neurotrophic factor (BDNF) gene Val66Met polymorphism, serotonin transporter-linked promoter region (5-HTTLPR), and FK506 binding protein 51 (FKBP5) gene rs1360780 in brain morphologic changes in patients with depression and in a non-clinical population. Individuals with the Met allele of BDNF Val66Met and a history of childhood adversity had reduced volume in the hippocampus and its subfields, amygdala, and PFC and thinner rostral ACC in a study of depressed patients and healthy controls. The S allele of 5-HTTLPR combined with exposure to childhood adversity or a poorer parenting environment was associated with a smaller hippocampal volume and subsequent onset of depression. The FKBP5 gene rs160780 had a significant interaction with childhood adversity in the white matter integrity of brain regions involved in emotion processing. This review identified that imaging genetic studies on childhood adversity may deepen our understanding on the neurobiological background of depression by scrutinizing complicated pathways of genetic factors, early psychosocial environments, and the accompanying morphologic changes in emotion-processing neural circuitry.

Resilience priming: Translational models for understanding resiliency and adaptation to early life adversity

Despite the increasing attention to early life adversity and its long-term consequences on health, behavior, and the etiology of neurodevelopmental disorders, our understanding of the adaptations and interventions that promote resiliency and rescue against such insults are underexplored. Specifically, investigations of the perinatal period often focus on negative events/outcomes. In contrast, positive experiences (i.e. enrichment/parental care//healthy nutrition) favorably influence development of the nervous and endocrine systems. Moreover, some stressors result in adaptations and demonstrations of later-life resiliency. This review explores the underlying mechanisms of neuroplasticity that follow some of these early life experiences and translates them into ideas for interventions in pediatric settings. The emerging role of the gut microbiome in mediating stress susceptibility is also discussed. Since many negative outcomes of early experiences are known, it is time to identify mechanisms and mediators that promote resiliency against them. These range from enrichment, quality parental care, dietary interventions and those that target the gut microbiota.

Childhood Trauma in Schizophrenia: Current Findings and Research Perspectives

Schizophrenia is a severe neuropsychiatric disorder with persistence of symptoms throughout adult life in most of the affected patients. This unfavorable course is associated with multiple episodes and residual symptoms, mainly negative symptoms and cognitive deficits. The neural diathesis-stress model proposes that psychosocial stress acts on a pre-existing vulnerability and thus triggers the symptoms of schizophrenia. Childhood trauma is a severe form of stress that renders individuals more vulnerable to developing schizophrenia; neurobiological effects of such trauma on the endocrine system and epigenetic mechanisms are discussed. Childhood trauma is associated with impaired working memory, executive function, verbal learning, and attention in schizophrenia patients, including those at ultra-high risk to develop psychosis. In these patients, higher levels of childhood trauma were correlated with higher levels of attenuated positive symptoms, general symptoms, and depressive symptoms; lower levels of global functioning; and poorer cognitive performance in visual episodic memory end executive functions. In this review, we discuss effects of specific gene variants that interact with childhood trauma in patients with schizophrenia and describe new findings on the brain structural and functional level. Additive effects between childhood trauma and brain-derived neurotrophic factor methionine carriers on volume loss of the hippocampal subregions cornu ammonis (CA)4/dentate gyrus and CA2/3 have been reported in schizophrenia patients. A functional magnetic resonance imaging study showed that childhood trauma exposure resulted in aberrant function of parietal areas involved in working memory and of visual cortical areas involved in attention. In a theory of mind task reflecting social cognition, childhood trauma was associated with activation of the posterior cingulate gyrus, precuneus, and dorsomedial prefrontal cortex in patients with schizophrenia. In addition, decreased connectivity was shown between the posterior cingulate/precuneus region and the amygdala in patients with high levels of physical neglect and sexual abuse during childhood, suggesting that disturbances in specific brain networks underlie cognitive abilities. Finally, we discuss some of the questionnaires that are commonly used to assess childhood trauma and outline possibilities to use recent biostatistical methods, such as machine learning, to analyze the resulting datasets.