Chongde Lin

Individual Differences in False Memory from Misinformation: Cognitive Factors

This research investigated the cognitive correlates of false memories that are induced by the misinformation paradigm. A large sample of Chinese college students (N=436) participated in a misinformation procedure and also took a battery of cognitive tests. Results revealed sizable and systematic individual differences in false memory arising from exposure to misinformation. False memories were significantly and negatively correlated with measures of intelligence (measured with Ravens Advanced Progressive Matrices and Wechsler Adult Intelligence Scale), perception (Motor-Free Visual Perception Test, Change Blindness, and Tone Discrimination), memory (Wechsler Memory Scales and 2-back Working Memory tasks), and face judgement (Face Recognition and Facial Expression Recognition). These findings suggest that people with relatively low intelligence and poor perceptual abilities might be more susceptible to the misinformation effect.

Traumatic Severity and Trait Resilience as Predictors of Posttraumatic Stress Disorder and Depressive Symptoms among Adolescent Survivors of the Wenchuan Earthquake

Purpose To examine the associations between trauma severity, trait resilience, and posttraumatic stress disorder (PTSD) and depressive symptoms among adolescent survivors of the Wenchuan earthquake, China. Methods 788 participants were randomly selected from secondary schools in the counties of Wenchuan and Maoxian, the two areas most severely affected by the earthquake. Participants completed four main questionnaires including the Child PTSD Symptom Scale, the Center for Epidemiologic Studies Depression Scale for Children, the Connor and Davidson’s Resilience Scale, and the Severity of Exposure to Earthquake Scale. Results After adjusting for the effect of age and gender, four aspects of trauma severity (i.e., direct exposure, indirect exposure, worry about others, and house damage) were positively associated with the severity of PTSD and depressive symptoms, whereas trait resilience was negatively associated with PTSD and depressive symptoms and moderated the relationship between subjective experience (i.e., worry about others) and PTSD and depressive symptoms. Conclusions Several aspects (i.e., direct exposure, indirect exposure, worry about others, and house damage) of earthquake experiences may be important risk factors for the development and maintenance of PTSD and depression. Additionally, trait resilience exhibits the beneficial impact on PTSD and depressive symptoms and buffers the effect of subjective experience (i.e., worry about others) on PTSD and depressive symptoms.

The relationship between DRM and misinformation false memories.

This research investigated the relationship between false memories induced by two different paradigms (misinformation and Deese–Roediger–McDermott [DRM]). The misinformation effect refers to the phenomenon that a person’s recollection of a witnessed event can be altered after exposure to misleading information about the event. DRM false memory represents the intrusion of words that are semantically related but not actually presented in the study session. Subjects (N = 432) completed both misinformation and DRM false memory tests. Results showed a small but significant correlation (r = .12, p = .02) between the misinformation and DRM false memories. Furthermore, using signal detection theory, we found that the discrimination ability index (d′) was related to both the misinformation and DRM false memories (r = −.12 and −.13, p = .01), while the response bias was related only to DRM false memory (r = −.46, p < .001). These results suggest that misinformation and DRM false memories generally involve different mechanisms and that their shared mechanism may involve the global discrimination ability.

The effects of extraversion, social support on the posttraumatic stress disorder and posttraumatic growth of adolescent survivors of the Wenchuan earthquake.

Objective The aim of this study was to examine the relationships among extraversion, social support, posttraumatic stress disorder and posttraumatic growth among adolescent survivors of the Wenchuan earthquake. Methods Six hundred thirty-eight participants were selected from the survivors of the 2008 Wenchuan earthquake. Participants completed four main questionnaires, including the Extraversion Subscale, the Social Support Scale, the Child PTSD Symptom Scale, and the Posttraumatic Growth Inventory. Results A bivariate correlation analysis revealed significant correlations among extraversion, social support, posttraumatic stress disorder and posttraumatic growth. Extraversion had significant indirect effects on posttraumatic stress disorder (β = −.037, p < .01) and posttraumatic growth (β = .077, p < .001) through social support. The results also indicated that extraversion had a significant direct effect on posttraumatic growth and a nonsignificant direct effect on posttraumatic stress disorder. Conclusions Social support fully mediates the relationship between extraversion and posttraumatic stress disorder and partially mediates the relationship between extraversion and posttraumatic growth. Psychological interventions and care for survivors of the earthquake should include the various functions and sources of social support and how they serve to benefit individuals.

Longitudinal linkages between depressive and posttraumatic stress symptoms in adolescent survivors following the Wenchuan earthquake in China: A three-wave, cross-lagged study

This study aimed to determine the relationships between depressive and posttraumatic stress disorder (PTSD) symptoms in a sample of adolescent survivors following the Wenchuan earthquake in China. Two-hundred adolescent survivors were reviewed at 12, 18 and 24-months post-earthquake. Depression and PTSD were assessed by two self-report questionnaires: The revised Center for Epidemiologic Studies Depression Scale for Children and the Revised Child PTSD Symptom Scale, respectively. The cross-lagged structural equation analysis with latent variables indicated that the PTSD symptoms and depression could be considered as two distinct and high-correlated constructs, and depression symptomatology pre-event could predict post-event PTSD. Depression symptoms play a crucial role in the development of PTSD symptoms. Implications of the results for psychological service providers to children and youth are discussed.

The Relationship Between Posttraumatic Stress Symptoms and Suicide Ideation Among Child Survivors Following the Wenchuan Earthquake

The association between posttraumatic stress disorder (PTSD) symptoms and suicide ideation was examined in a sample of 2,298 child survivors of the Wenchuan earthquake. Results indicated that intrusion, avoidance, hyperarousal symptom clusters, and PTSD total score were significantly associated with suicide ideation. Except for intrusion, other measures of PTSD remained as statistically significant correlates of suicide ideation even after controlling for age, gender, direct exposure, indirect exposure, and depression. Furthermore, results showed that PTSD symptoms had an indirect influence on suicide ideation that was mediated by depression. The findings suggest that avoidance and hyperarousal symptom clusters of PTSD may be two important indicators of suicide ideation among child survivors of the Wenchuan earthquake. Implications of the results for intervention and prevention of suicide behavior are discussed.

The SEMA5A gene is associated with hippocampal volume, and their interaction is associated with performance on Raven's Progressive Matrices

The Allen Brain Atlas shows that the semaphorin 5A (SEMA5A) gene, which encodes an important protein for neurogenesis and neuronal apoptosis, is predominantly expressed in the human hippocampus. Structural and functional neuroimaging studies have further shown that the hippocampus plays an important role in the performance on Ravens Progressive Matrices (RPM), a measure of reasoning ability and general fluid intelligence. Thus far, however, no study has examined the relationships between the SEMA5A gene polymorphism, hippocampal volume, and RPM performance. The current study collected both structural MRI, genetic, and behavioral data in 329 healthy Chinese adults, and examined associations between SEMA5A variants, hippocampal volume, and performance on RAPM (the advanced form of RPM). After controlling for intracranial volume (ICV), sex, and age, SEMA5A genetic polymorphism at the SNP rs42352 had the strongest association with hippocampal volume (p=0.00000552 and 0.000103 for right and left hippocampal volumes, respectively), with TT homozygotes having higher hippocampal volume than the other genotypes. Furthermore, there was a high correlation between right hippocampal volume and RAPM performance (r=0.42, p=0.0000509) for SEMA5A rs42352 TT homozygotes. This study provides the first evidence for the involvement of the SEMA5A gene in hippocampal structure and their interaction on RAPM performance. Future studies of the hippocampus-RPM associations should consider genetic factors as potential moderators.

The DOPA decarboxylase (DDC) gene is associated with alerting attention

DOPA decarboxylase (DDC) is involved in the synthesis of dopamine, norepinephrine and serotonin. It has been suggested that genes involved in the dopamine, norepinephrine, and cholinergic systems play an essential role in the efficiency of human attention networks. Attention refers to the cognitive process of obtaining and maintaining the alert state, orienting to sensory events, and regulating the conflicts of thoughts and behavior. The present study tested seven single nucleotide polymorphisms (SNPs) within the DDC gene for association with attention, which was assessed by the Attention Network Test to detect three networks of attention, including alerting, orienting, and executive attention, in a healthy Han Chinese sample (N=451). Association analysis for individual SNPs indicated that four of the seven SNPs (rs3887825, rs7786398, rs10499695, and rs6969081) were significantly associated with alerting attention. Haplotype-based association analysis revealed that alerting was associated with the haplotype G-A-T for SNPs rs7786398-rs10499695-rs6969081. These associations remained significant after correcting for multiple testing by max(T) permutation. No association was found for orienting and executive attention. This study provides the first evidence for the involvement of the DDC gene in alerting attention. A better understanding of the genetic basis of distinct attention networks would allow us to develop more effective diagnosis, treatment, and prevention of deficient or underdeveloped alerting attention as well as its related prevalent neuropsychiatric disorders.

True but not false memories are associated with the HTR2A gene

Previous research reported that serotonin receptor 2A gene (HTR2A) polymorphisms were associated with memory. However, it is unknown whether these genetic variants were associated with both true and false memories. The current study of 336 Han Chinese subjects tested 30 single nucleotide polymorphisms (SNPs) within the HTR2A gene for potential associations with true and false memories. False memories were assessed using the Deese-Roediger-McDermott (DRM) paradigm, in which people falsely remember semantically related (but unpresented) words. We found that 11 SNPs within the HTR2A gene were associated with true memory (p=0.000076-0.043). The associations between true memory and seven adjacent SNPs (i.e., rs1923888, rs1745837, rs9567739, rs3742279, rs655888, rs655854, and rs2296972) were still significant after multiple testing corrections. Haplotype-based association analysis revealed that, true memory was positively associated with haplotype A-C-C-G-C-T-A for these seven adjacent SNPs (p=0.000075), which was still significant after multiple testing correction. Only one SNP rs655854 was associated with false memory (p=0.023), and it was not significant after multiple testing correction. This study replicates, in an Asian population, that genetic variation in HTR2A is associated with episodic memory, and also suggests that this association is restricted to true memory.

Associations between the CNTNAP2 gene, dorsolateral prefrontal cortex, and cognitive performance on the Stroop task.

The CNTNAP2 (contactin-associated protein-like 2) gene, highly expressed in the human prefrontal cortex, has been linked with autism and language impairment. Potential relationships between CNTNAP2, dorsolateral prefrontal cortex (DLPFC), and cognition have been suggested by previous clinical studies, but have not been directly examined in the same study. The current study collected structural MRI, genetic, and behavioral data in 317 healthy Chinese adults, and examined associations between CNTNAP2 variants, DLPFC, and cognitive performance (measured by the Stroop task). After controlling for intracranial volume, sex, and age, the CNTNAP2 genetic polymorphism at SNP rs7809486 had the strongest association with bilateral DLPFC volume (p=0.00015 and 0.00014 for left and right DLPFC volumes, respectively), with GG homozygotes having greater bilateral DLPFC volumes and surface areas than the other genotypes. Furthermore, TT homozygotes of CNTNAP2 rs4726946 (a nearby SNP that had moderate linkage disequilibrium with rs7809486) had greater left DLPFC volume and surface area, and better cognitive performance than the other genotypes. Subjects with greater left DLPFC surface area had better cognitive performance. Importantly, the left DLPFC surface area mediated the association between the CNTNAP2 rs4726946 genotype and cognitive performance. This study provides the first evidence for associations among the CNTNAP2 gene, left DLPFC structure, and cognitive control.