scholarly journals Morphometry Difference of the Hippocampal Formation Between Blind and Sighted Individuals

2021 ◽  
Vol 15 ◽  
Author(s):  
Ningning Pan ◽  
Ke Zheng ◽  
Yanna Zhao ◽  
Dan Zhang ◽  
Changxu Dong ◽  
...  

The detailed morphometry alterations of the human hippocampal formation (HF) for blind individuals are still understudied. 50 subjects were recruited from Yantai Affiliated Hospital of Binzhou Medical University, including 16 congenital blindness, 14 late blindness, and 20 sighted controls. Volume and shape analysis were conducted between the blind (congenital or late) and sighted groups to observe the (sub)regional alterations of the HF. No significant difference of the hippocampal volume was observed between the blind and sighted subjects. Rightward asymmetry of the hippocampal volume was found for both congenital and late blind individuals, while no significant hemispheric difference was observed for the sighted controls. Shape analysis showed that the superior and inferior parts of both the hippocampal head and tail expanded, while the medial and lateral parts constrained for the blind individuals as compared to the sighted controls. The morphometry alterations for the congenital blind and late blind individuals are nearly the same. Significant expansion of the superior part of the hippocampal tail for both congenital and late blind groups were observed for the left hippocampi after FDR correction. Current results suggest that the cross-model plastic may occur in both hemispheres of the HF to improve the navigation ability without the stimuli of visual cues, and the alteration is more prominent for the left hemisphere.

2018 ◽  
Vol 15 (12) ◽  
pp. 1151-1160 ◽  
Author(s):  
Zihan Jiang ◽  
Huilin Yang ◽  
Xiaoying Tang

Objective: In this study, we investigated the influence that the pathology of Alzheimer’s disease (AD) exerts upon the corpus callosum (CC) using a total of 325 mild cognitive impairment (MCI) subjects, 155 AD subjects, and 185 healthy control (HC) subjects. Method: Regionally-specific morphological CC abnormalities, as induced by AD, were quantified using a large deformation diffeomorphic metric curve mapping based statistical shape analysis pipeline. We also quantified the association between the CC shape phenotype and two cognitive measures; the Mini Mental State Examination (MMSE) and the Alzheimer’s Disease Assessment Scale-Cognitive Behavior Section (ADAS-cog). To identify AD-relevant areas, CC was sub-divided into three subregions; the genu, body, and splenium (gCC, bCC, and sCC). Results: We observed significant shape compressions in AD relative to that in HC, mainly concentrated on the superior part of CC, across all three sub-regions. The HC-vs-MCI shape abnormalities were also concentrated on the superior part, but mainly occurred on bCC and sCC. The significant MCI-vs-AD shape differences, however, were only detected in part of sCC. In the shape-cognition association, significant negative correlations to ADAS-cog were detected for shape deformations at regions belonging to gCC and sCC and significant positive correlations to MMSE at regions mainly belonging to sCC. Conclusion: Our results suggest that the callosal shape deformation patterns, especially those of sCC, linked tightly to the cognitive decline in AD, and are potentially a powerful biomarker for monitoring the progression of AD.


2021 ◽  
Author(s):  
Reiko Hori ◽  
Eiji Shibata ◽  
Iwao Okajima ◽  
Masahiro Matsunaga ◽  
Tomohiro Umemura ◽  
...  

Abstract Background: The coronavirus disease 2019 (COVID-19) pandemic has changed our daily life. Owing to the imposed restrictions, many educational facilities have introduced remote teaching. This study aims to understand the impact of remote teaching on Japanese university students' sleeping habits.Methods: The participants were medical university students. We used data from an ongoing longitudinal sleeping habits survey. For 684 participants who enrolled in the university during 2018–2020, multilevel analyses of sleep duration during weekdays and weekends across 3 years were conducted, adjusting for gender, grade, place of stay, sleep problems and lifestyle habits. Results: Among the participants, 356 male (mean ± standard deviation: 22 ± 3, 18–37 years old) and 288 female (22 ± 3, 18–32 years old) students in 2018, 365 male (24 ± 3,18–36 years old) and 284 female (22 ± 2, 18–33 years old) students in 2019, and 226 male (20 ± 3,18-36 years old) and 167 female (21 ± 2, 18–34 years old) students in 2020 answered the questionnaire. The mean sleep duration during weekdays (in minutes) was 407.6 ± 60.3 in 2018, 406.9 ± 63.0 in 2019, and 417.3 ± 80.9 in 2020. The mean sleep duration during weekends (in minutes) was 494.5 ± 82.5 in 2018, 488.3 ± 87.9 in 2019, and 462.3 ± 96.4 in 2020. The analysis showed that sleep duration during weekdays was associated with the place of stay and survey year. Moreover, students reported significantly longer sleep duration during weekdays in 2020 than 2019, but no significant difference in sleep duration between 2018 and 2019. Sleep duration during weekends was found to be associated with the survey year, gender and always doing something before going to bed. Sleep duration during weekends was shorter in 2020 than 2019 and longer in male students and students who always do something before going to bed. Ten students were reported to have a delayed sleep phase in 2020. Conclusions: Students' sleep duration increased during weekdays and decreased during weekends in 2020. This difference could be explained by the COVID-19 pandemic and the introduction of remote teaching.


PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0242416
Author(s):  
Salomé Le Franc ◽  
Mathis Fleury ◽  
Mélanie Cogne ◽  
Simon Butet ◽  
Christian Barillot ◽  
...  

Introduction Illusion of movement induced by tendon vibration is an effective approach for motor and sensory rehabilitation in case of neurological impairments. The aim of our study was to investigate which modality of visual feedback in Virtual Reality (VR) associated with tendon vibration of the wrist could induce the best illusion of movement. Methods We included 30 healthy participants in the experiment. Tendon vibration inducing illusion of movement (wrist extension, 100Hz) was applied on their wrist during 3 VR visual conditions (10 times each): a moving virtual hand corresponding to the movement that the participants could feel during the tendon vibration (Moving condition), a static virtual hand (Static condition), or no virtual hand at all (Hidden condition). After each trial, the participants had to quantify the intensity of the illusory movement on a Likert scale, the subjective degree of extension of their wrist and afterwards they answered a questionnaire. Results There was a significant difference between the 3 visual feedback conditions concerning the Likert scale ranking and the degree of wrist’s extension (p<0.001). The Moving condition induced a higher intensity of illusion of movement and a higher sensation of wrist’s extension than the Hidden condition (p<0.001 and p<0.001 respectively) than that of the Static condition (p<0.001 and p<0.001 respectively). The Hidden condition also induced a higher intensity of illusion of movement and a higher sensation of wrist’s extension than the Static condition (p<0.01 and p<0.01 respectively). The preferred condition to facilitate movement’s illusion was the Moving condition (63.3%). Conclusions This study demonstrated the importance of carefully selecting a visual feedback to improve the illusion of movement induced by tendon vibration, and the increase of illusion by adding VR visual cues congruent to the illusion of movement. Further work will consist in testing the same hypothesis with stroke patients.


2021 ◽  
Vol 9 ◽  
Author(s):  
Xiaoyan Mao ◽  
Runxiu Yin ◽  
Gaoyuan Sun ◽  
Yan Zhou ◽  
Chunhui Yang ◽  
...  

Background: 6-Mercaptopurine (6-MP) is the cornerstone of current antileukemia regimen and contributes greatly to improve the survival of pediatric acute lymphoblastic leukemia (ALL) patients. However, 6-MP dose-related toxicities limit its application. TPMT, NUDT15, and ITPA are pharmacogenetic markers predicting 6-MP-related toxicities, but their genetic polymorphisms differ from those of ethnic populations. In Yunnan province, a multiethnic region of China, we had no genetic data to predict 6-MP toxicities. In this study, we evaluated the most common variants involved in 6-MP metabolism—TPMT*3C (rs1142345), NUDT15 c.415C&gt;T (rs116855232), and ITPA c.94C&gt;A (rs1127354) variants—in our cohort of pediatric ALL patients.Methods: A total of 149 pediatric ALL patients in the Affiliated Children's Hospital of Kunming Medical University (Yunnan Children's Medical Center) from 2017 to 2019 were enrolled in this retrospective study. We assessed the TPMT*3C (rs1142345), NUDT15 c.415C&gt;T (rs116855232), and ITPA c.94C&gt;A (rs1127354) frequencies and evaluated association between genotypes and 6-MP toxicities, 6-MP dose, and event-free survival (EFS) in these ALL patients.Results: The allele frequencies of TPMT*3C (rs1142345), NUDT15 c.415C&gt;T (rs116855232), and ITPA c.94C&gt;A (rs1127354) were 1.34%, 14.43%, and 18.79%, respectively. Only NUDT15 c.415C&gt;T (rs116855232) was strongly associated with 6-MP toxicity and 6-MP tolerable dose. NUDT15 c.415C&gt;T was related to leukopenia, p = 0.008, OR = 2.743 (95% CI: 1.305–5.768). The T allele was significantly correlated with 6-MP tolerable dose, dose of NUDT15 c.415C&gt;T wild genotype CC 39.80 ± 1.32 mg/m2, heterozygotes CT 35.20 ± 2.29 mg/m2, and homozygotes TT 18.95 ± 3.95 mg/m2. 6-MP tolerable dose between CC and TT had a significant difference, p = 0.009. Between CC and CT, and CT and TT, they had no significant difference. EFS showed no significant difference among NUDT15 c.415C&gt;T genotypes.Conclusion:NUDT15 c.415C&gt;T (rs116855232) was an optimal predictor for 6-MP toxicity and tolerable dose in pediatric ALL patients from Yunnan province, a multiethnic region in China, and would play an important role in precise therapy for ALL.


2011 ◽  
Vol 26 (S2) ◽  
pp. 432-432
Author(s):  
V. Nejati

Background and aimBlindness cause functional and structural change in brain. The aim of this study is evaluation and comparison of selective attention and inhibition in acquired blinds and matched sightedMethodForty five Acquired Blinds of war veteran and fifty six healthy volunteers participated in this cross sectional study. Auditory Stroop Test is used for evaluation of selective attention and inhibitory control. Independent T Test was used for comparing blind with sighted.ResultsFindings show significant difference between two groups so that sighted subjects have higher performance in accuracy and reaction time of all stage of stroop task.ConclusionWe concluded that acquired blinds didn’t have any preference in selective attention and inhibitory control versus matched sighted.


2020 ◽  
Vol 68 (4) ◽  
pp. 882-887
Author(s):  
Cameron B Wilhoit ◽  
Nathan D Holman ◽  
Don C Rockey

ObjectiveLack of clear evidence in red blood cell (RBC) transfusion during gastrointestinal bleeding has led to varied recommendations over the years. However, studies in broad areas of medicine have provided evidence about appropriate RBC transfusion thresholds, and a ‘landmark’ study published in 2013 provided evidence in patients with upper gastrointestinal (UGI) bleeding. We hypothesized that the response to the evidence would lead to improved RBC transfusion practice. Our aim was to determine the response in RBC transfusion practices at our institution.DesignWe examined RBC transfusion practices in patients with UGI bleeding who presented to the Medical University of South Carolina from January 2010 through December 2013. We abstracted extensive clinical data including demographic, medical history (comorbidities), medications, physical examination findings, laboratory data, endoscopic data, and RBC transfusion practices. We considered appropriate RBC transfusion to have occurred when performed for a hemoglobin level of <70 g/L.Results270 patients hospitalized with UGI bleeding had 606 RBC transfusions; 355 transfusions in 107 patients were appropriate, and 251 transfusions in 163 were inappropriate. In 2010, 2011, and 2012, the rates of appropriate RBC transfusions were 61/124 (49%), 92/172 (53%), and 84/142 (59%), respectively. There was a statistically significant difference in appropriate transfusions in 2013 (118/168 (70%)) compared with 2012 (84/142 (59%), p=0.003), as well as during 2010–2012 (237/438 (54%), p≤0.003).ConclusionsThe data suggest that there was an improvement in RBC transfusion practices after a landmark study. However, the data also highlight that RBC transfusion practices in UGI bleeding remain imperfect.


Neurology ◽  
1998 ◽  
Vol 51 (2) ◽  
pp. 357-362 ◽  
Author(s):  
M. Hashimoto ◽  
H. Kitagaki ◽  
T. Imamura ◽  
N. Hirono ◽  
T. Shimomura ◽  
...  

Objective: Dementia with Lewy bodies (DLB) is emerging as a common cause of degenerative dementia. A recent pathologic study has indicated that the medial temporal lobe in patients with DLB was less atrophic than that in patients with AD. The purpose of this study was to examine whether medial temporal MRI volumetry was useful to differentiate DLB from AD clinically.Methods: We compared the volumes of the hippocampal formation, amygdaloid complex, and whole brain in 27 patients with probable DLB (based on the criteria of the Consortium on DLB International Workshop), 27 patients with probable AD(based on criteria of the National Institute of Neurological Disease and Stroke/Alzheimer's Disease and Related Disorders Association), and 27 normal elderly subjects using an MRI-based volumetric technique. The three groups were matched for age and sex. Severity of cognitive disturbances represented by their Mini-Mental State Examination score was comparable between the DLB and AD groups.Results: Hippocampal volume (normalized to intracranial volume) in the DLB group was significantly larger than that in the AD group, but significantly smaller than that in the normal control group. There were no significant differences in the amygdala and whole-brain volume between the DLB group and the AD group, but the atrophies of the amygdala and whole brain were more severe in the DLB group than those in the control group.Conclusions: These findings indicate the usefulness of MRI hippocampal volumetry in clinically discriminating patients with DLB from patients with AD.


2019 ◽  
Vol 43 (3) ◽  
pp. 345-349 ◽  
Author(s):  
Xiao-Min Zhang ◽  
Jian-Yun Yu ◽  
Yuan Yang ◽  
Cui-Ping Feng ◽  
Jing Lyu ◽  
...  

A small private online course (SPOC) supports blended learning on a small scale, enabling students to have a more comprehensive and deeper learning experience. It also provides instructors with a flexible and feasible model to better understand the students’ learning needs and to supervise students’ learning behaviors. In this study, we adopted SPOC flipped classroom blended teaching in the physiology course for clinical undergraduate students of Kunming Medical University. Compared with the control group [lecture-based learning (LBL)], the SPOC flipped classroom method significantly increased the scores of students in the preclass test (65.13 ± 12.45 vs. 53.46 ± 8.09, SPOC vs. LBL) and postclass test (80.43 ± 14.29 vs. 69.01 ± 12.81, SPOC vs. LBL), which is induced by students’ increased interest in self-learning. More importantly, the significant difference between the preclass scores of the two groups suggested that the video lecture-based preview is more effective than the textbook-based preview. The study indicated that the SPOC flipped classroom was effective in enhancing the examination scores of students, reflecting an improved learning efficiency and a deeper understanding of the knowledge. In summary, the flipped classroom based on SPOC improves learning outcomes compared with LBL and has a wide application in the learning of basic medical courses.


1993 ◽  
Vol 70 (4) ◽  
pp. 1516-1529 ◽  
Author(s):  
T. Ono ◽  
K. Nakamura ◽  
H. Nishijo ◽  
S. Eifuku

1. Neural activity in the monkey hippocampal formation (HF) was analyzed during a spatial moving task in which the monkey was guided by auditory and visual cues and when stimuli were presented from various directions. The monkey could control a motorized, movable device (cab) and its route to a target location by pressing the proper one of five available bars in an appropriate sequence (spatial moving task). In any of several locations in the field, neural responses were evident in relation to the presentation of various objects or human movement in some relative direction (left, anterior, right) as a directional stimulus test. 2. Of 238 hippocampal neurons analyzed, 172 (72.3%, 238-66) responded in either the spatial moving task, or to the direction from which stimulation was presented, or to the location of the monkey in the field, or to some combination of these. 3. The activity of 79 (33.2%) neurons was higher when the monkey was in some specific location in the field during the spatial moving task, regardless of the approach route or other task parameters (place related neurons). 4. Responses to the task cues in the spatial moving task were evident in 110 (46.3%) neurons (task related neurons). Of these, 77 (32.4%) neurons were not place related. The remaining 33 (13.9%) neurons were both task related and place related. These neurons responded to task cues in only that part of the field in which place related responses occurred. The neural response to the task cues disappeared when the monkey moved out of the place response region. The place related and task related neural responses disappeared when the room light was switched off. Thus information from the environment outside of the cab contributed to the place related and task related responses. 5. Stimuli presented from certain specific directions induced responses, selectively, in 41 (17.2%) of the neurons (direction related neurons). The dependence of the preferred direction was described in one of three ways--egocentric, allocentric, or place-direction specific. Nineteen egocentric neurons responded to a stimulus only when it was presented from a certain direction relative to the orientation of the monkey, regardless of the location of the monkey. Eleven allocentric neurons responded to a stimulus only when it was presented at a particular position in the room, regardless of the location or orientation of the monkey.(ABSTRACT TRUNCATED AT 400 WORDS)


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