We studied a male with acquired prosopagnosia using a battery of implicit association tests (IATs) to investigate whether observing faces varying by social category would activate the patient's implicit social biases. We also asked him to categorize faces explicitly by race, gender, and political party. The patient, G.B., was marginally slower to categorize black compared to white faces. He showed congruency effects in the race and celebrity IATs, but not in the gender or political IATs. These results indicate that G.B. possesses an implicit social sensitivity to certain facial stimuli despite an inability to overtly recognize familiar faces. The results demonstrate that social biases can be retrieved based on facial stimuli via pathways bypassing the fusiform gyri. Thus the IAT effect can be added to the list of covert recognition effects found in prosopagnosia.
Previous studies showed that liberals and conservatives differ in cognitive style. Liberals are more flexible, and tolerant of complexity and novelty, whereas conservatives are more rigid, are more resistant to change, and prefer clear answers. We administered a set of compound remote associate problems, a task extensively used to differentiate problem-solving styles (via insight or analysis). Using this task, several researches have proven that self-reports, which differentiate between insight and analytic problem-solving, are reliable and are associated with two different neural circuits. In our research we found that participants self-identifying with distinct political orientations demonstrated differences in problem-solving strategy. Liberals solved significantly more problems via insight instead of in a step-by-step analytic fashion. Our findings extend previous observations that self-identified political orientations reflect differences in cognitive styles. More specifically, we show that type of political orientation is associated with problem-solving strategy. The data converge with previous neurobehavioural and cognitive studies indicating a link between cognitive style and the psychological mechanisms that mediate political beliefs.
Magnitude comparison, calculation verification, and short-term memory span experiments were conducted as a means of investigating number processing in deaf college students. The level of accuracy shown by the deaf students did not differ from that shown by their hearing peers. However, mean response times for the deaf students were greater than those of the hearing students for all experimental tasks. The authors question the importance of development, working memory, and sign communication as factors that may contribute to explanations of the experimental results.
In: Peace and conflict: journal of peace psychology ; the journal of the Society for the Study of Peace, Conflict, and Violence, Peace Psychology Division of the American Psychological Association, Band 24, Heft 2, S. 245-249
We assessed political attitudes using the Implicit Association Test (IAT) in which participants were presented faces and names of well-known Democrat and Republican politicians along with positive and negative words while undergoing functional MRI. We found a significant behavioral IAT effect for the face, but not the name, condition. The fMRI face condition results indicated that ventromedial and anterior prefrontal cortices were activated during political attitude inducement. Amygdala and fusiform gyrus were activated during perceptual processing of familiar faces. Amygdala activation also was associated with measures of strength of emotion. Frontopolar activation was positively correlated with an implicit measure of bias and valence strength (how strongly the participants felt about the politicians), while strength of affiliation with political party was negatively correlated with lateral PFC, lending support to the idea that two distinct but interacting networks-one emphasizing rapid, stereotypic, and emotional associative knowledge and the other emphasizing more deliberative and factual knowledge-cooperate in the processing of politicians. Our findings of ventromedial PFC activation suggests that when processing the associative knowledge concerned with politicians, stereotypic knowledge is activated, but in addition, the anterior prefrontal activations indicate that more elaborative, reflective knowledge about the politician is activated.
Penetrating traumatic brain injury is associated with deficits in cognitive tasks including comprehension and memory, and also with impairments in tasks of daily living. In naturalistic settings, one important component of cognitive task performance is event segmentation, the ability to parse the ongoing stream of behavior into meaningful units. Event segmentation ability is associated with memory performance and with action control, but is not well assessed by standard neuropsychological assessments or laboratory tasks. Here, we measured event segmentation and memory in a sample of 123 male military veterans aged 59–81 who had suffered a traumatic brain injury as young men, and 34 demographically similar controls. Participants watched movies of everyday activities and segmented them to identify fine-grained or coarse-grained events, and then completed tests of recognition memory for pictures from the movies and of memory for the temporal order of actions in the movies. Lesion location and volume were assessed with computed tomography imaging. Patients with traumatic brain injury were impaired on event segmentation. Those with larger lesions had larger impairments for fine segmentation and also impairments for both memory measures. Further, the degree of memory impairment was statistically mediated by the degree of event segmentation impairment. There was some evidence that lesions to the ventromedial prefrontal cortex (vmPFC) selectively impaired coarse segmentation; however, lesions outside of a priori regions of interest also were associated with impaired segmentation. One possibility is that the effect of vmPFC damage reflects the role of prefrontal event knowledge representations in ongoing comprehension. These results suggest that assessment of naturalistic event comprehension can be a valuable component of cognitive assessment in cases of traumatic brain injury, and that interventions aimed at event segmentation could be clinically helpful.
Given the determinant role of ventromedial prefrontal cortex (vmPFC) in valuation, we examined whether vmPFC lesions also modulate how people scale political beliefs. Patients with penetrating traumatic brain injury (pTBI; N = 102) and healthy controls (HCs; N = 31) were tested on the political belief task, where they rated 75 statements expressing political opinions concerned with welfare, economy, political involvement, civil rights, war and security. Each statement was rated for level of agreement and scaled along three dimensions: radicalism, individualism and conservatism. Voxel-based lesion-symptom mapping (VLSM) analysis showed that diminished scores for the radicalism dimension (i.e. statements were rated as less radical than the norms) were associated with lesions in bilateral vmPFC. After dividing the pTBI patients into three groups, according to lesion location (i.e. vmPFC, dorsolateral prefrontal cortex [dlPFC] and parietal cortex), we found that the vmPFC, but not the dlPFC, group had reduced radicalism scores compared with parietal and HC groups. These findings highlight the crucial role of the vmPFC in appropriately valuing political behaviors and may explain certain inappropriate social judgments observed in patients with vmPFC lesions.
Neuronal plasticity is a fundamental factor in cognitive outcome following traumatic brain injury. Brain-derivedneurotrophic factor (BDNF), a member of the neurotrophin family, plays an important role in this process. While thereare many ways to measure cognitive outcome, general cognitive intelligence is a strong predictor of everyday decisionmaking,occupational attainment, social mobility and job performance. Thus it is an excellent measure of cognitive outcomefollowing traumatic brain injury (TBI). Although the importance of the single-nucleotide polymorphisms polymorphism oncognitive function has been previously addressed, its role in recovery of general intelligence following TBI is unknown. Wegenotyped male Caucasian Vietnam combat veterans with focal penetrating TBI (pTBI) (n = 109) and non-head injuredcontrols (n = 38) for 7 BDNF single-nucleotide polymorphisms. Subjects were administrated the Armed Forces QualificationTest (AFQT) at three different time periods: pre-injury on induction into the military, Phase II (10–15 years post-injury, andPhase III (30–35 years post-injury). Two single-nucleotide polymorphisms, rs7124442 and rs1519480, were significantlyassociated with post-injury recovery of general cognitive intelligence with the most pronounced effect at the Phase II timepoint, indicating lesion-induced plasticity. The genotypes accounted for 5% of the variance of the AFQT scores,independently of other significant predictors such as pre-injury intelligence and percentage of brain volume loss. Thesedata indicate that genetic variations in BDNF play a significant role in lesion-induced recovery following pTBI. Identifying theunderlying mechanism of this brain-derived neurotrophic factor effect could provide insight into an important aspect ofpost-traumatic cognitive recovery.
Neuronal plasticity is a fundamental factor in cognitive outcome following traumatic brain injury. Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, plays an important role in this process. While there are many ways to measure cognitive outcome, general cognitive intelligence is a strong predictor of everyday decision-making, occupational attainment, social mobility and job performance. Thus it is an excellent measure of cognitive outcome following traumatic brain injury (TBI). Although the importance of the single-nucleotide polymorphisms polymorphism on cognitive function has been previously addressed, its role in recovery of general intelligence following TBI is unknown. We genotyped male Caucasian Vietnam combat veterans with focal penetrating TBI (pTBI) (n = 109) and non-head injured controls (n = 38) for 7 BDNF single-nucleotide polymorphisms. Subjects were administrated the Armed Forces Qualification Test (AFQT) at three different time periods: pre-injury on induction into the military, Phase II (10–15 years post-injury, and Phase III (30–35 years post-injury). Two single-nucleotide polymorphisms, rs7124442 and rs1519480, were significantly associated with post-injury recovery of general cognitive intelligence with the most pronounced effect at the Phase II time point, indicating lesion-induced plasticity. The genotypes accounted for 5% of the variance of the AFQT scores, independently of other significant predictors such as pre-injury intelligence and percentage of brain volume loss. These data indicate that genetic variations in BDNF play a significant role in lesion-induced recovery following pTBI. Identifying the underlying mechanism of this brain-derived neurotrophic factor effect could provide insight into an important aspect of post-traumatic cognitive recovery.
Both traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD) are common problems resulting from military service, and both have been associated with increased risk of cognitive decline and dementia resulting from Alzheimer's disease (AD) or other causes. This study aims to use imaging techniques and biomarker analysis to determine whether traumatic brain injury (TBI) and/or PTSD resulting from combat or other traumas increase the risk for AD and decrease cognitive reserve in Veteran subjects, after accounting for age. Using military and Department of Veterans Affairs records, 65 Vietnam War veterans with a history of moderate or severe TBI with or without PTSD, 65 with ongoing PTSD without TBI, and 65 control subjects are being enrolled in this study at 19 sites. The study aims to select subject groups that are comparable in age, gender, ethnicity, and education. Subjects with mild cognitive impairment (MCI) or dementia are being excluded. However, a new study just beginning, and similar in size, will study subjects with TBI, subjects with PTSD, and control subjects with MCI. Baseline measurements of cognition, function, blood, and cerebrospinal fluid bio-markers; magnetic resonance images (structural, diffusion tensor, and resting state blood-level oxygen dependent (BOLD) functional magnetic resonance imaging); and amyloid positron emission tomographic (PET) images with florbetapir are being obtained. One-year follow-up measurements will be collected for most of the baseline procedures, with the exception of the lumbar puncture, the PET imaging, and apolipoprotein E genotyping. To date, 19 subjects with TBI only, 46 with PTSD only, and 15 with TBI and PTSD have been recruited and referred to 13 clinics to undergo the study protocol. It is expected that cohorts will be fully recruited by October 2014. This study is a first step toward the design and statistical powering of an AD prevention trial using at-risk veterans as subjects, and provides the basis for a larger, more comprehensive study of ...
Both traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD) are common problems resulting from military service, and both have been associated with increased risk of cognitive decline and dementia resulting from Alzheimer's disease (AD) or other causes. This study aims to use imaging techniques and biomarker analysis to determine whether traumatic brain injury (TBI) and/or PTSD resulting from combat or other traumas increase the risk for AD and decrease cognitive reserve in Veteran subjects, after accounting for age. Using military and Department of Veterans Affairs records, 65 Vietnam War veterans with a history of moderate or severe TBI with or without PTSD, 65 with ongoing PTSD without TBI, and 65 control subjects are being enrolled in this study at 19 sites. The study aims to select subject groups that are comparable in age, gender, ethnicity, and education. Subjects with mild cognitive impairment (MCI) or dementia are being excluded. However, a new study just beginning, and similar in size, will study subjects with TBI, subjects with PTSD, and control subjects with MCI. Baseline measurements of cognition, function, blood, and cerebrospinal fluid biomarkers; magnetic resonance images (structural, diffusion tensor, and resting state blood-level oxygen dependent (BOLD) functional magnetic resonance imaging); and amyloid positron emission tomographic (PET) images with florbetapir are being obtained. One-year follow-up measurements will be collected for most of the baseline procedures, with the exception of the lumbar puncture, the PET imaging, and apolipoprotein E genotyping. To date, 19 subjects with TBI only, 46 with PTSD only, and 15 with TBI and PTSD have been recruited and referred to 13 clinics to undergo the study protocol. It is expected that cohorts will be fully recruited by October 2014. This study is a first step toward the design and statistical powering of an AD prevention trial using at-risk veterans as subjects, and provides the basis for a larger, more comprehensive study of dementia risk factors in veterans.
Both traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD) are common problems resulting from military service, and both have been associated with increased risk of cognitive decline and dementia resulting from Alzheimer's disease (AD) or other causes. This study aims to use imaging techniques and biomarker analysis to determine whether traumatic brain injury (TBI) and/or PTSD resulting from combat or other traumas increase the risk for AD and decrease cognitive reserve in Veteran subjects, after accounting for age. Using military and Department of Veterans Affairs records, 65 Vietnam War veterans with a history of moderate or severe TBI with or without PTSD, 65 with ongoing PTSD without TBI, and 65 control subjects are being enrolled in this study at 19 sites. The study aims to select subject groups that are comparable in age, gender, ethnicity, and education. Subjects with mild cognitive impairment (MCI) or dementia are being excluded. However, a new study just beginning, and similar in size, will study subjects with TBI, subjects with PTSD, and control subjects with MCI. Baseline measurements of cognition, function, blood, and cerebrospinal fluid biomarkers; magnetic resonance images (structural, diffusion tensor, and resting state blood-level oxygen dependent (BOLD) functional magnetic resonance imaging); and amyloid positron emission tomographic (PET) images with florbetapir are being obtained. One-year follow-up measurements will be collected for most of the baseline procedures, with the exception of the lumbar puncture, the PET imaging, and apolipoprotein E genotyping. To date, 19 subjects with TBI only, 46 with PTSD only, and 15 with TBI and PTSD have been recruited and referred to 13 clinics to undergo the study protocol. It is expected that cohorts will be fully recruited by October 2014. This study is a first step toward the design and statistical powering of an AD prevention trial using at-risk veterans as subjects, and provides the basis for a larger, more comprehensive study of dementia risk factors in veterans.
In: Gao , Y , Wang , T , Yu , X , Ferrari , R , Hernandez , D G , Nalls , M A , Rohrer , J D , Ramasamy , A , Kwok , J B J , Dobson-Stone , C , Brooks , W S , Schofield , P R , Halliday , G M , Hodges , J R , Piguet , O , Bartley , L , Thompson , E , Haan , E , Hernández , I , Ruiz , A , Boada , M , Borroni , B , Padovani , A , Cruchaga , C , Cairns , N J , Benussi , L , Binetti , G , Ghidoni , R , Forloni , G , Albani , D , Galimberti , D , Fenoglio , C , Serpente , M , Scarpini , E , Clarimón , J , Lleó , A , Blesa , R , Waldö , M L , Nilsson , K , Nilsson , C , Mackenzie , I R A , Hsiung , G Y R , Mann , D M A , Grafman , J , Morris , C M , Attems , J , Griffiths , T D , Rowe , J B , Nielsen , J E , Hjermind , L E & International FTD-Genomics Consortium (IFGC) 2020 , ' Mendelian randomization implies no direct causal association between leukocyte telomere length and amyotrophic lateral sclerosis ' , Scientific Reports , vol. 10 , no. 1 , 12184 . https://doi.org/10.1038/s41598-020-68848-9
We employed Mendelian randomization (MR) to evaluate the causal relationship between leukocyte telomere length (LTL) and amyotrophic lateral sclerosis (ALS) with summary statistics from genome-wide association studies (n = ~ 38,000 for LTL and ~ 81,000 for ALS in the European population; n = ~ 23,000 for LTL and ~ 4,100 for ALS in the Asian population). We further evaluated mediation roles of lipids in the pathway from LTL to ALS. The odds ratio per standard deviation decrease of LTL on ALS was 1.10 (95% CI 0.93–1.31, p = 0.274) in the European population and 0.75 (95% CI 0.53–1.07, p = 0.116) in the Asian population. This null association was also detected between LTL and frontotemporal dementia in the European population. However, we found that an indirect effect of LTL on ALS might be mediated by low density lipoprotein (LDL) or total cholesterol (TC) in the European population. These results were robust against extensive sensitivity analyses. Overall, our MR study did not support the direct causal association between LTL and the ALS risk in neither population, but provided suggestive evidence for the mediation role of LDL or TC on the influence of LTL and ALS in the European population.
In: Gao , Y , Wang , T , Yu , X , Ferrari , R , Hernandez , D G , Nalls , M A , Rohrer , J D , Ramasamy , A , Kwok , J B J , Dobson-Stone , C , Brooks , W S , Schofield , P R , Halliday , G M , Hodges , J R , Piguet , O , Bartley , L , Thompson , E , Haan , E , Hernández , I , Ruiz , A , Boada , M , Borroni , B , Padovani , A , Cruchaga , C , Cairns , N J , Benussi , L , Binetti , G , Ghidoni , R , Forloni , G , Albani , D , Galimberti , D , Fenoglio , C , Serpente , M , Scarpini , E , Clarimón , J , Lleó , A , Blesa , R , Waldö , M L , Nilsson , K , Nilsson , C , Mackenzie , I R A , Hsiung , G Y R , Mann , D M A , Grafman , J , Morris , C M , Attems , J , Griffiths , T D , McKeith , I G , Thomas , A J , Pietrini , P , Huey , E D , Wassermann , E M , Baborie , A , Jaros , E , Tierney , M C , Pastor , P , Razquin , C , Ortega-Cubero , S , Alonso , E , Perneczky , R , Diehl-Schmid , J , Alexopoulos , P , Kurz , A , Rainero , I , Rubino , E , Pinessi , L , Rogaeva , E , George-Hyslop , P S , Rossi , G , Tagliavini , F , Giaccone , G , Rowe , J B , Schlachetzki , J C M , Uphill , J , Collinge , J , Mead , S , Danek , A , Van Deerlin , V M , Grossman , M , Trojanowski , J Q , van der Zee , J , Cruts , M , Van Broeckhoven , C , Cappa , S F , Leber , I , Hannequin , D , Golfier , V , Vercelletto , M , Brice , A , Nacmias , B , Sorbi , S , Bagnoli , S , Piaceri , I , Nielsen , J E , Hjermind , L E , Riemenschneider , M , Mayhaus , M , Ibach , B , Gasparoni , G , Pichler , S , Gu , W , Rossor , M N , Fox , N C , Warren , J D , Spillantini , M G , Morris , H R , Rizzu , P , Heutink , P , Snowden , J S , Rollinson , S , Richardson , A , Gerhard , A , Bruni , A C , Maletta , R , Frangipane , F , Cupidi , C , Bernardi , L , Anfossi , M , Gallo , M , Conidi , M E , Smirne , N , Rademakers , R , Baker , M , Dickson , D W , Graff-Radford , N R , Petersen , R C , Knopman , D , Josephs , K A , Boeve , B F , Parisi , J E , Seeley , W W , Miller , B L , Karydas , A M , Rosen , H , van Swieten , J C , Dopper , E G P , Seelaar , H , Pijnenburg , Y A L , Scheltens , P , Logroscino , G , Capozzo , R , Novelli , V , Puca , A A , Franceschi , M , Postiglione , A , Milan , G , Sorrentino , P , Kristiansen , M , Chiang , H H , Graff , C , Pasquier , F , Rollin , A , Deramecourt , V , Lebouvier , T , Kapogiannis , D , Ferrucci , L , Pickering-Brown , S , Singleton , A B , Hardy , J , Momeni , P , Zhao , H , Zeng , P & International FTD-Genomics Consortium (IFGC) 2020 , ' Mendelian randomization implies no direct causal association between leukocyte telomere length and amyotrophic lateral sclerosis ' , Scientific Reports , vol. 10 , no. 1 , 12184 . https://doi.org/10.1038/s41598-020-68848-9
We employed Mendelian randomization (MR) to evaluate the causal relationship between leukocyte telomere length (LTL) and amyotrophic lateral sclerosis (ALS) with summary statistics from genome-wide association studies (n = ~ 38,000 for LTL and ~ 81,000 for ALS in the European population; n = ~ 23,000 for LTL and ~ 4,100 for ALS in the Asian population). We further evaluated mediation roles of lipids in the pathway from LTL to ALS. The odds ratio per standard deviation decrease of LTL on ALS was 1.10 (95% CI 0.93–1.31, p = 0.274) in the European population and 0.75 (95% CI 0.53–1.07, p = 0.116) in the Asian population. This null association was also detected between LTL and frontotemporal dementia in the European population. However, we found that an indirect effect of LTL on ALS might be mediated by low density lipoprotein (LDL) or total cholesterol (TC) in the European population. These results were robust against extensive sensitivity analyses. Overall, our MR study did not support the direct causal association between LTL and the ALS risk in neither population, but provided suggestive evidence for the mediation role of LDL or TC on the influence of LTL and ALS in the European population.