Atsushi Sakuma

Brain structural changes as vulnerability factors and acquired signs of post-earthquake stress.

Many survivors of severe disasters, even those without posttraumatic stress disorder (PTSD), need psychological support. To understand the pathogenesis of PTSD symptoms and prevent the development of PTSD, the critical issue is to distinguish neurological abnormalities as vulnerability factors from acquired signs of PTSD symptoms in the early stage of adaptation to the trauma in the normal population. The neurological underpinnings of PTSD have been well characterized, but the causal relationships with the traumatic event are still unclear. We examined 42 non-PTSD subjects to find brain morphometric changes related to the severity of PTSD symptoms in a longitudinal magnetic resonance imaging study extending through the Great East Japan Earthquake. We found that regional grey matter volume (rGMV) in the right ventral anterior cingulate cortex (ACC) before the earthquake, and decreased rGMV in the left orbitofrontal cortex (OFC) through the earthquake were negatively associated with PTSD symptoms. Our results indicate that subjects with smaller GMV in the ACC before the earthquake, and subjects with decreased GMV in the OFC through the earthquake were likely to have PTSD symptoms. As the ACC is involved in processing of fear and anxiety, our results indicate that these processing are related to vulnerability for PTSD symptoms. In addition, decreased OFC volume was induced by failing to extinct conditioned fear soon after the traumatic event. These findings provide a better understanding of posttraumatic responses in early stage of adaptation to the trauma and may contribute to the development of effective methods to prevent PTSD.

White Matter Microstructural Changes as Vulnerability Factors and Acquired Signs of Post-Earthquake Distress

Many survivors of severe disasters need psychological support, even those not suffering post-traumatic stress disorder (PTSD). The critical issue in understanding the psychological response after experiencing severe disasters is to distinguish neurological microstructural underpinnings as vulnerability factors from signs of emotional distress acquired soon after the stressful life event. We collected diffusion-tensor magnetic resonance imaging (DTI) data from a group of healthy adolescents before the Great East Japan Earthquake and re-examined the DTIs and anxiety levels of 30 non-PTSD subjects from this group 3–4 months after the earthquake using voxel-based analyses in a longitudinal DTI study before and after the earthquake. We found that the state anxiety level after the earthquake was negatively associated with fractional anisotropy (FA) in the right anterior cingulum (Cg) before the earthquake (r = −0.61, voxel level p<0.0025, cluster level p<0.05 corrected), and positively associated with increased FA changes from before to after the earthquake in the left anterior Cg (r = 0.70, voxel level p<0.0025, cluster level p<0.05 corrected) and uncinate fasciculus (Uf) (r = 0.65, voxel level p<0.0025, cluster level p<0.05 corrected). The results demonstrated that lower FA in the right anterior Cg was a vulnerability factor and increased FA in the left anterior Cg and Uf was an acquired sign of state anxiety after the earthquake. We postulate that subjects with dysfunctions in processing fear and anxiety before the disaster were likely to have higher anxiety levels requiring frequent emotional regulation after the disaster. These findings provide new evidence of psychophysiological responses at the neural network level soon after a stressful life event and might contribute to the development of effective methods to prevent PTSD.

Neural Mechanism for Mirrored Self-face Recognition

Self-face recognition in the mirror is considered to involve multiple processes that integrate 2 perceptual cues: temporal contingency of the visual feedback on ones action (contingency cue) and matching with self-face representation in long-term memory (figurative cue). The aim of this study was to examine the neural bases of these processes by manipulating 2 perceptual cues using a “virtual mirror” system. This system allowed online dynamic presentations of real-time and delayed self- or other facial actions. Perception-level processes were identified as responses to only a single perceptual cue. The effect of the contingency cue was identified in the cuneus. The regions sensitive to the figurative cue were subdivided by the response to a static self-face, which was identified in the right temporal, parietal, and frontal regions, but not in the bilateral occipitoparietal regions. Semantic- or integration-level processes, including amodal self-representation and belief validation, which allow modality-independent self-recognition and the resolution of potential conflicts between perceptual cues, respectively, were identified in distinct regions in the right frontal and insular cortices. The results are supportive of the multicomponent notion of self-recognition and suggest a critical role for contingency detection in the co-emergence of self-recognition and empathy in infants.

The association between cognitive deficits and depressive symptoms in at-risk mental state: A comparison with first-episode psychosis

Cognitive deficits and a high prevalence of depressive symptoms have been reported in at-risk mental state (ARMS) for psychosis, but the relationships between these variables remain unclear. The Brief Assessment of Cognition in Schizophrenia (BACS) was administered to 50 individuals with ARMS, 50 with first-episode psychosis (FEP), and 30 healthy controls (HC). Clinical symptoms were assessed by the Positive and Negative Syndrome Scale (PANSS) and the Beck Depression Inventory-2nd edition (BDI-II). Composite z-scores in BACS were compared between the three groups. Pearson correlations between composite z-scores on the BACS and indices of clinical symptoms were compared in the ARMS and FEP groups. The mean composite z-scores on the BACS for the ARMS (-2.82) and FEP (-2.85) groups were significantly lower than the HC group (P<0.001); no differences between the ARMS and FEP groups emerged (P=0.995). Cognitive deficits and depressive symptoms were significantly correlated in the ARMS group (PANSS depression: r=-0.36, P=0.010; BDI-II: r=-0.34, P=0.02), while the correlation between cognitive deficits and negative symptoms was significant in the FEP group (r=-0.46, P=0.001) and approached significance in the ARMS group (r=-0.25, P=0.08). The correlation between cognitive deficits and depressive symptoms significantly differed between the ARMS and FEP groups (PANSS depression: Z=2.50, P=0.012; BDI-II: Z=1.96, P=0.0499). Thus, a relationship between cognitive deficits and depression appears to be specific to ARMS compared to FEP.

Reduced Thickness of the Anterior Cingulate Cortex in Individuals With an At-Risk Mental State Who Later Develop Psychosis

BACKGROUND Despite the fact that only a part of the individuals with at-risk mental state (ARMS) for psychosis do develop psychosis, biological markers of future transition to psychosis have not been well documented. Structural abnormality of the anterior cingulate gyrus (ACG), which probably exists prior to the onset of psychosis, could be such a risk marker. METHODS We conducted a multicenter magnetic resonance imaging (MRI) study of 3 scanning sites in Japan. 1.5-T 3D MRI scans were obtained from 73 ARMS subjects and 74 age- and gender-matched healthy controls. We measured thickness, volume, and surface area of the ACG using labeled cortical distance mapping and compared these measures among healthy controls, ARMS subjects who later converted to overt psychosis (ARMS-C), and those who did not (ARMS-NC). RESULTS Seventeen of 73 (23%) ARMS subjects developed overt psychosis within the follow-up period. The thickness of the left ACG was significantly reduced in ARMS-C relative to healthy subjects (P = .026) while both ARMS-C (P = .001) and ARMS-NC (P = .01) had larger surface areas of the left ACG compared with healthy controls. CONCLUSION Further studies will be needed to identify potential markers of future transition to psychosis though cortical thinning of the ACG might be one of the candidates.

Psychological trauma after the Great East Japan Earthquake

The Great East Japan Earthquake (GEJE) struck the northeastern part of Japan on 11 March 2011 and triggered a devastating tsunami, causing widespread destruction along the coast of northeastern Japan. The tsunami also led to an accident at the Fukushima Daiichi nuclear power plant. Incidents occurring in such major disasters are known to lead to psychological trauma. This paper has summarized English‐language documentation regarding GEJE‐related psychological trauma or post‐traumatic stress disorder (PTSD). Research thus far has reported the possibility of higher probable PTSD prevalence among residents of the GEJE areas than in the average Japanese population during normal times. At the very least, many people have experienced trauma symptoms at self‐recognition levels 1 year or longer after the disaster. It appears that the percentage of persons with high PTSD risk was higher in regions with radiation‐related impacts than in regions where the main damage was caused by the earthquake and tsunami. Results have not been limited to showing relations between severe exposure to a traumatic event and PTSD symptoms but also show that a variety of factors, including social factors, has been shown to interact with PTSD symptoms. The fact that Japanese society as a whole united against the trauma of the GEJE may have worked to minimize the effects of trauma. To grasp a full picture of the effects of psychological trauma due to the GEJE, further surveys and research are necessary. It will be necessary to continue engagements related to these problems and issues into the future.

Synthesis of the Pb-based superconductor of the Pb3201 phase (Pb2Cu)Sr0.9La1.1CuO6+δ by the modified polymerized complex method

Abstract We have succeeded in obtaining single-phase samples of the Pb3201 phase (Pb2Cu)Sr0.9La1.1CuO6+δ by the modified polymerized complex method. At the first step of the synthesis, a transparent gel is found to be obtained by increasing the molar ratio of citric acid to total metal ions up to 5 without controlling the pH of the solution and without ethylene glycol. Secondly, the precursor is prepared by calcining the transparent gel. Finally, highly homogeneous samples with the onset temperature of the superconducting transition, ∼ 37 K, are obtained by sintering the precursor and subsequently annealing it. Moreover, the Pb3201 phase is found to be stable only for x = 1.1 in (Pb2Cu)Sr2−xLaxCuO6+δ.

Deficits of cognitive theory of mind and its relationship with functioning in individuals with an at-risk mental state and first-episode psychosis

Disturbance of theory of mind (ToM) and its relationship with functioning in schizophrenia is well documented; however, this is unclear in spectrum disorders like at-risk mental state (ARMS) and first-episode psychosis (FEP). To assess mental state reasoning ability, the total score of the Theory of Mind Picture Stories Task questionnaire was compared among 36 Japanese individuals with ARMS, 40 with FEP, and 25 healthy controls (HC). Pearsons correlations between ToM performance and global and social functioning indices were examined. ToM performance for FEP and ARMS subjects was significantly lower than that for HC, though the significance of the difference between the ARMS and HC disappeared when controlling for premorbid IQ. ToM deficits in ARMS subjects were confirmed only in the comprehension of higher-order false belief. Only among FEP subjects were ToM performance and global functioning significantly correlated, though the significance disappeared when controlling for neurocognitive performance or dose of antipsychotics. No significant correlation between ToM performance and social functioning was observed in the FEP and ARMS groups. The current findings suggest that ToM deficits emerge in ARMS subjects confined within a higher-order domain, and that the relationship between ToM impairment and functional deterioration might be established after psychosis onset.

Effects of extra oxygen on the physical properties in the Pb3201 phase of (Pb2Cu)Sr0.9La1.1CuO6+δ prepared by the polymerized complex method

Abstract We have investigated the effects of extra oxygen on the crystal structure, transport properties and superconductivity in the Pb3201 phase of (Pb 2 Cu)Sr 9 La 1.1 CuO 6+δ prepared by the polymerized complex method. A structural phase transition from orthorhombic to tetragonal phase is observed with increasing δ. The sample is orthorhombic for 0 ≲ δ ≲ 0.4, tetragonal for 1.7 ≲ δ ≲ 2 and a mixture of the orthorhombic and tetragonal phasse for 0.4 ≲ δ ≲ 1.7. In the orthorhombic phase of δ ≲ 0.3−0.4, T c increases with increasing δ, owing to the increase of holes in the CuO 2 sheets from the extra oxygen. In the tetragonal phase, on the other hand, the superconductivity disappears on account of the small hole concentration in the CuO 2 sheets, owing to the increase of the Pb valence from +2 to +4.

Effects of post-traumatic growth on the dorsolateral prefrontal cortex after a disaster

The relating to others factor of post-traumatic growth (PTG), which involves mutual help and a strong sense of connection with humanity, is important for young people who are coping with stress. The prefrontal cortex (PFC), especially the dorsolateral PFC (DLPFC), may play an important role in post-traumatic stress disorder (PTSD) with regard to coping and resilience. We hypothesized that the neural correlates of PTG may be responsible for resilience to the correlates of PTSD. Our study tested this hypothesis by examining whether measures of PTG, particularly the measures of relating to others after a disaster, were associated with increased regional grey matter volume (rGMV) in the PFC by assessing individuals who had experienced the East Japan Great Earthquake. We calculated the delta-rGMV by subtracting the rGMV obtained 3 months before the disaster from the rGMV obtained after this disaster using voxel-based morphometry. The magnetic resonance imaging data obtained from 26 subjects (M/F: 21/5; age: 21.2 ± 1.6 yrs.) showed that the total scores on a PTG inventory and the subscore for relating to others at the post-assessment were positively and significantly associated with the delta-rGMV in the right DLPFC. The DLPFC seems to be the main neural correlate of PTG.