Young Normal Subjects Research Articles

26. Rhythmic activity of leg muscles during standing in healthy subjects

Traditionally, the stretch and possibly polysynaptic reflexes are considered the mainstay of antigravity leg muscles. We found evidence of a different mechanism. In a group of young normal subjects, surface EMG was recorded from tibialis anterior, soleus, vastus medialis and biceps femoris muscles in quiet upright stance without and with balance perturbation. In quiet stance, a modest amount of activity could be recorded from the soleus and the biceps femoris only, and none from tibialis anterior and vastus medialis. Such activity was organized in bursts whose duration ranged 50–100 ms, and frequency of 8–12/s. Simultaneous recording of the centre of pressure via stabilometric platform, showed that when a forward shift occurred, frequency and amplitude of the soleus bursts increased, but all activity ceased in a backward shift. When balance was perturbed by a backward tilt, the very first ensuing activity was a brief response by the soleus (weak stretch reflex) followed by several bursts of the tibialis anterior. Little if any activity was recorded from the thigh muscles. We conclude that action of antigravity muscles of the leg seemed more linked to modulation of a rhythmic preordinated activity rather than to a simple reflex response.

Surface electromyography analysis of blepharoptosis correction by transconjunctival incisions

Upper eyelid movement depends on the antagonistic actions of orbicularis oculi muscle and levator aponeurosis. Blepharoptosis is an abnormal drooping of upper eyelid margin with the eye in primary position of gaze. Transconjunctival incisions for upper eyelid ptosis correction have been a well-developed technique. Conventional prognosis however depends on clinical observations and lacks of quantitatively analysis for the eyelid muscle controlling. This study examines the possibility of using the assessments of temporal correlation in surface electromyography (SEMG) as a quantitative description for the change of muscle controlling after operation. Eyelid SEMG was measured from patients with blepharoptosis preoperatively and postoperatively, as well as, for comparative study, from young and aged normal subjects. The data were analyzed using the detrended fluctuation analysis method. The results show that the temporal correlation of the SEMG signals can be characterized by two indices associated with the correlation properties in short and long time scales demarcated at 3ms, corresponding to the time scale of neural response. Aging causes degradation of the correlation properties at both time scales, and patient group likely possess more serious correlation degradation in long-time regime which was improved moderately by the ptosis corrections. We propose that the temporal correlation in SEMG signals may be regarded as an indicator for evaluating the performance of eyelid muscle controlling in postoperative recovery.

The effect of network template from normal subjects in the detection of network impairment.

This study aimed to provide a simple way to approach group differences by independent component analysis when researching functional connectivity changes of resting-state network in brain disorders. We used baseline resting state functional magnetic resonance imaging from the Alzheimer's disease neuroimaging initiative dataset and performed independent component analysis based on different kinds of subject selection, by including two downloaded templates and single-subject independent component analysis method. All conditions were used to calculate the functional connectivity of the default mode network, and to test group differences and evaluate correlation with cognitive measurements and hippocampal volume. The default mode network functional connectivity results most fitting clinical evaluations were from templates based on young healthy subjects and the worst results were from heterogeneous or more severe disease groups or single-subject independent component analysis method. Using independent component analysis network maps derived from normal young subjects to extract all individual functional connectivities provides significant correlations with clinical evaluations.

Why musical memory can be preserved in advanced Alzheimer's disease.

Musical memory is considered to be partly independent from other memory systems. In Alzheimer's disease and different types of dementia, musical memory is surprisingly robust, and likewise for brain lesions affecting other kinds of memory. However, the mechanisms and neural substrates of musical memory remain poorly understood. In a group of 32 normal young human subjects (16 male and 16 female, mean age of 28.0 ± 2.2 years), we performed a 7 T functional magnetic resonance imaging study of brain responses to music excerpts that were unknown, recently known (heard an hour before scanning), and long-known. We used multivariate pattern classification to identify brain regions that encode long-term musical memory. The results showed a crucial role for the caudal anterior cingulate and the ventral pre-supplementary motor area in the neural encoding of long-known as compared with recently known and unknown music. In the second part of the study, we analysed data of three essential Alzheimer's disease biomarkers in a region of interest derived from our musical memory findings (caudal anterior cingulate cortex and ventral pre-supplementary motor area) in 20 patients with Alzheimer's disease (10 male and 10 female, mean age of 68.9 ± 9.0 years) and 34 healthy control subjects (14 male and 20 female, mean age of 68.1 ± 7.2 years). Interestingly, the regions identified to encode musical memory corresponded to areas that showed substantially minimal cortical atrophy (as measured with magnetic resonance imaging), and minimal disruption of glucose-metabolism (as measured with (18)F-fluorodeoxyglucose positron emission tomography), as compared to the rest of the brain. However, amyloid-β deposition (as measured with (18)F-flobetapir positron emission tomography) within the currently observed regions of interest was not substantially less than in the rest of the brain, which suggests that the regions of interest were still in a very early stage of the expected course of biomarker development in these regions (amyloid accumulation → hypometabolism → cortical atrophy) and therefore relatively well preserved. Given the observed overlap of musical memory regions with areas that are relatively spared in Alzheimer's disease, the current findings may thus explain the surprising preservation of musical memory in this neurodegenerative disease.

Accommodation and pupil responses to random-dot stereograms

We investigated the dynamics of accommodative and pupillary responses to random-dot stereograms presented in crossed and uncrossed disparity in six visually normal young adult subjects (mean age=25.8±3.1 years). Accommodation and pupil measures were monitored monocularly with a custom built photorefraction system while subjects fixated at the center of a random-dot stereogram. On each trial, the stereogram initially depicted a flat plane and then changed to depict a sinusoidal corrugation in depth while fixation remained constant. Increase in disparity specified depth resulted in pupil constriction during both crossed and uncrossed disparity presentations. The change in pupil size between crossed and uncrossed disparity conditions was not significantly different (p>0.05). The change in pupil size was also accompanied by a small concomitant increase in accommodation. In addition, the dynamic properties of pupil responses varied as a function of their initial (starting) diameter. The finding that accommodation and pupil responses increased with disparity regardless of the sign of retinal disparity suggests that these responses were driven by apparent depth rather than shifts in mean simulated distance of the stimulus. Presumably the need for the increased depth of focus when viewing stimuli extended in depth results in pupil constriction which also results in a concomitant change in accommodation. Starting position effects in pupil response confirm the non-linearity in the operating range of the pupil.

Inter‐ and Intra‐Laboratory Variability of Glycemic and Insulinemic Indexes

ObjectivesThe glycemic index (GI) concept was developed by Jenkins et al in 1981 to classify the glycemic impact of carbohydrate (CHO)‐containing foods. This study aimed at quantifying inter‐ and intra‐laboratory variability on GI, Insulin Index (II), glycemic and insulinemic responses after standardising the protocols in 3 different labs.MethodsAt least 15 healthy young normal weight subjects with HOMA‐IR < 1.7 were recruited by each lab. They underwent 9 sessions to test a glucose solution (3 times) or 6 different cereal products. The 3 selected labs used the validated GI method (ISO method 26642:2010). Insulin assay and subject selection criteria were standardised.ResultsGI values for the 6 different products (mean ± SEM) ranged from 44 ± 4 to 92 ± 8. For a same product, the between‐labs differences range was 0 ‐ 11. No lab effect but significant product effects were observed for GI and iAUC glycemia. II values of the 6 different products ranged between 54 ± 3 and 85 ± 9. For a same product, the between‐labs differences range was 0 ‐ 21. Significant lab * product interaction effect was observed for II on 1 product. iAUC insulinemia displayed both significant lab and product effects. Inter‐individual and intra‐individual coefficient of variability (CV) ranges were 20 ‐ 28 % and 18 ‐ 30%, respectively for iAUC glycemia and 35 ‐ 51 % and 22 ‐ 43 %, respectively for iAUC insulinemia.ConclusionNo significant lab effect and good product discrimination was observed on GI. Insulin parameters display statistically significant differences between the labs showing the difficulty to compare the results on these parameters.

Event-Related Synchronization and Desynchronization of High-Frequency Electroencephalographic Activity during a Visual Go/No-Go Paradigm

Objective: High-frequency electroencephalography (EEG) activity has been observed in association with cognitive processing, including stimulus perception, consciousness and selective attention, in humans. The aim of this study was to compare visual-motor integrated processing between execution and inhibition of a motor response using event-related synchronization (ERS) and desynchronization (ERD) in the 15- to 80-Hz range and to investigate a relationship between event-related potentials (ERPs) and ERS/ERD in 10 normal young subjects. Methods: EEGs were recorded from 21 scalp sites during a visual go/no-go paradigm. For ERPs, 40 artifact-free trials were averaged off-line referenced to linked ear lobes. In the β and γ bands, ERS and ERD were calculated by time-frequency analysis. Results: Go N2 and no-go N2 were elicited 200-250 ms after stimuli, and their distributions were predominant at Fz. Go P3 was predominantly elicited 340-360 ms after stimuli at Pz, whereas no-go P3 was predominantly elicited 360-380 ms after stimuli at Cz. ERD of the β band at Fz and Cz during 300-600 ms showed in the go condition, whereas ERD showed between 39 and 42 Hz at F3 in the no-go condition. Conclusion: Oscillatory cortical response-related β and γ activities differ between the processing of execution and inhibition in motor responses. β ERDs in the sensorimotor areas with go stimuli may be related to motor responses, and γ ERDs in the left frontal area with no-go stimuli may be involved in the processing of inhibition of motor responses.

Normative Reference Ranges for Binocular Summation as a Function of Age for Low Contrast Letter Charts

Purpose: Binocular summation (BiS), defined as the superiority of binocular over monocular viewing on visual threshold tasks, is most often studied in laboratory settings. Few studies have evaluated BiS with readily available clinical tools. Low contrast acuity (LCA) charts are increasingly popular in clinical research, yet their utility in detecting BiS has not been evaluated.Methods: 129 normal subjects aged 3 to 85 years were prospectively enrolled and underwent monocular and binocular testing using 2.5% and 1.25% Sloan LCA charts and Pelli-Robson (PR) contrast sensitivity (CS) charts at an academic institution. Subjects also underwent similar testing with Early Treatment Diabetic Retinopathy Study (ETDRS) VA charts. BiS was calculated as the difference between the better eye and binocular scores.Results: Monocular and binocular scores decreased with increasing age for all metrics. The mean (±SD) BiS scores for 2.5% and 1.25% Sloan LCA were 6 ± 4.5 and 3 ± 5 letters, respectively. BiS score was 4.5 ± 7 letters for PR charts and 2 ± 3 letters for ETDRS VA. There was a significant effect of age on BiS for the low contrast metrics (P ≤ 0.001 for all), but not for high-contrast ETDRS VA. Linear regression revealed significant associations between increased interocular difference (IOD) in acuity and decreased BiS for all tests, and associations between increasing age and decreased BiS for the LCA tests.Conclusion: Of the clinical tests evaluated, 2.5% and 1.25% Sloan LCA charts most readily demonstrated BiS in young normal subjects. BiS declined with increasing age and increased IOD. Median values presented in this study may be useful for future clinical studies utilizing LCA.

Template based rotation: A method for functional connectivity analysis with a priori templates

Functional connectivity magnetic resonance imaging (fcMRI) is a powerful tool for understanding the network level organization of the brain in research settings and is increasingly being used to study large-scale neuronal network degeneration in clinical trial settings. Presently, a variety of techniques, including seed-based correlation analysis and group independent components analysis (with either dual regression or back projection) are commonly employed to compute functional connectivity metrics. In the present report, we introduce template based rotation,11TBR MATLAB source code and template maps are available at: http://mrtools.mgh.harvard.edu/index.php/TBR. a novel analytic approach optimized for use with a priori network parcellations, which may be particularly useful in clinical trial settings. Template based rotation was designed to leverage the stable spatial patterns of intrinsic connectivity derived from out-of-sample datasets by mapping data from novel sessions onto the previously defined a priori templates. We first demonstrate the feasibility of using previously defined a priori templates in connectivity analyses, and then compare the performance of template based rotation to seed based and dual regression methods by applying these analytic approaches to an fMRI dataset of normal young and elderly subjects. We observed that template based rotation and dual regression are approximately equivalent in detecting fcMRI differences between young and old subjects, demonstrating similar effect sizes for group differences and similar reliability metrics across 12 cortical networks. Both template based rotation and dual-regression demonstrated larger effect sizes and comparable reliabilities as compared to seed based correlation analysis, though all three methods yielded similar patterns of network differences. When performing inter-network and sub-network connectivity analyses, we observed that template based rotation offered greater flexibility, larger group differences, and more stable connectivity estimates as compared to dual regression and seed based analyses. This flexibility owes to the reduced spatial and temporal orthogonality constraints of template based rotation as compared to dual regression. These results suggest that template based rotation can provide a useful alternative to existing fcMRI analytic methods, particularly in clinical trial settings where predefined outcome measures and conserved network descriptions across groups are at a premium.

Routine lumbar puncture for the early diagnosis of Alzheimer's disease. Is it safe?

Routine lumbar puncture for the early diagnosis of Alzheimer's disease. Is it safe?

The functional muscle–bone unit in subjects of varying BMD

This study used the "functional muscle-bone unit" concept to investigate muscle-bone interaction of the lumbar spine in subjects of varying bone mineral density. It was found that unit bone mass corresponded to a relatively more muscle mass in subjects with reduced bone mineral density, indicating a relatively higher mechanical load from muscles exerted on trabecular bone. Bone is an architecturally adaptive tissue which responds to mechanical loading. This study is proposed to use "functional muscle-bone unit" to reflect this muscle-bone interaction at spine in subjects with different bone mineral density. The study was carried out in young normal subjects (21 females; age, 29 ± 3) and elderly subjects (155 females; age, 73 ± 3.9) with varying bone mineral density. Cross-sectional area of paravertebral muscle groups was measured in MR images to indicate the muscle mass, while the bone mineral content by dual X-ray absorptiometry was used to represent the bone mass. The functional muscle-bone unit was calculated as the ratio between the bone mass to muscle mass. It showed that with aging, the muscle mass decreased with the bone mass losing. However, more pronounced reduction was found in bone mass than in muscle mass in the subjects with lower bone mineral density. Muscle-bone interaction was changed in elderly, especially in those with osteoporosis. Unit bone mass corresponded to a higher muscle mass in subjects with reduced bone mineral density than those normal subjects. This may be contributory to the occurrence of nontraumatic vertebral fractures in elderly subjects with reduced bone mineral density.

Effect of Short-term Exercise on Appetite, Energy Intake and Energy-regulating Hormones.

Objective(s) : The purpose of this study was to investigate effects of short-term aerobic exercise on energy intake, appetite and energy-regulating hormones in free-living men and women. Sixteen (eight men, eight women) sedentary young normal weight subjects participated in two experimental conditions with two days apart: five days control with no exercise, and five days exercise (55% MHRR for 45 min/day). Subjects recorded dietary intake using a food diary and self-weighed intake during each five days. Appetite questionnaire (visual analogue scale) was completed each morning in the fasted state. Blood samples were taken in the morning on the 6th day in fasting status after control and exercise conditions. No significant changes were found in absolute energy intake, appetite rate and level of acylated ghrelin and leptin between conditions in both sexes. In women, insulin concentration decreased significantly after exercise. Relative energy intake was significantly lower after exercise in men. On average, women compensated for about 23% of the exercise-induced energy deficit but men did not (-10%). Our findings show that low-intensity exercise for five consecutive days cannot create a negative energy balance in women. It seems that women are more resistant to exercise-induced energy deficit.

SŁUCHOWE ODPOWIEDZI BEHAWIORALNE I ELEKTROFIZJOLOGICZNE U DOROSŁYCH: OCENA OŚRODKOWEGO PRZETWARZANIA SŁUCHOWEGO

BackgroundIn addition to well known declines in the peripheral auditory system successful perception of speech is dependent on behavioural factors, as well as sound processing at subcortical and cortical levels. We hypothesized that cause and hence localization of impairment in the brain may be diverse in young and elderly people with hearing impairment, accordingly not always related with aging. The aim of the study is to determine the hallmarks of auditory behaviour and auditory cortical evoked responses that could be used in audiology clinics to help explain deficits in speech recognition in young and elderly listeners and recognize the most indicative effects of cortical auditory evoked potentials associated with difficulties of speech intelligibility.Material and MethodsThree groups of adults participated: young normal hearing, young and elderly subjects with difficulty to understand speech especially in complex listening environments despite normal pure tone thresholds. We supposed that differences could be found between young and elderly subjects. Procedure involved behavioural hearing tests, dichotic word tests and sentence recognition test in quiet and noise, and electrophysiological measures as cortical auditory evoked potential components P1, N1, P2, P3 in quiet and noise.ResultsSignificant correlation was found between hearing behavioural tests and auditory cortical evoked potentials. This dichotic study demonstrated differences in cortical processing in people with good hearing, young and elderly listeners with speech recognition difficulties. Results provide information about central tests showing significant decrease of perception in young and elderly participants with hearing impairment and it is most strongly associated with event related potential response P3. Sensitivity to signal intensity level significantly changes in the group of young and elderly subjects with hearing impairment for responses P1, N1, P2(p<0.5).ConclusionsDespite of resembling results from behaviour tests outcomes of auditory evoked potentials mark less influence of signal intensity level latencies in young then in older subject group. They could be useful in audiology practice for clinical diagnostics and evaluation of hearing rehabilitation.

English

Older patients with type 2 diabetes mellitus have a two- to four-fold increased risk of myocardial infarction. This study aims to determine the association between oxidative stress and advanced glycation end product (AGE). Human serum samples from normal older subjects (n = 31), older diabetic patients without myocardial infarction (n = 33), older diabetic patients with myocardial infarction (n = 32), older non-diabetic with myocardial infarction (n = 30) and normal young subjects (n = 31) were investigated. Positive significant correlation was observed between serum AGE and malondialdehyde in older diabetic and non-diabetic patients with myocardial infarction. Negative significant correlation was observed between AGE and vitamin-E in older diabetic and non-diabetic patients with myocardial infarction. However, malondialdehyde and serum AGE were found to be significantly (P < 0.001) higher in older diabetic and non-diabetic patients with and without myocardial infarction as compared with older control subjects. In contrast to all four older groups, the serum AGE was significantly (P < 0.001) lower in young control subjects. This study revealed that AGE was positively associated with markers of oxidative stress in the older groups.   Key words: Advanced glycation end products, myocardial infarction, diabetes.

健常若年者を対象としたTitmus Stereo TestsとNew Stereo Testsの比較・検討

健常若年者を対象としたTitmus Stereo TestsとNew Stereo Testsの比較・検討

Cardiovascular effects of music by entraining cardiovascular autonomic rhythms music therapy update: tailored to each person, or does one size fit all?

Music goes back a very long way in human experience. Music therapy is now used in many disparate areas-from coronary care units to rehabilitation after a stroke. But its widespread adoption has a poor scientific evidence base, founded more on enthusiasm than on proper evaluation in any controlled way. This has led to a lack of clarity about whether any particular type of music is superior, or whether different types of music should be tailored to differing individuals. We therefore conducted a series of controlled studies in which we examined the effects of different styles of music-from raga to jazz-presented in random order to normal young subjects (both musically trained or not). We found that contrary to many beliefs the effect of a style of music was similar in all subjects, whatever their individual music taste. We also found that this effect appeared to operate at a sub-conscious level through the autonomic nervous system. Furthermore, musical or verbal phrases of a 10s duration (which coincided with the normal circulatory 'Mayer' waves) induced bigger excursions in blood pressure and heart rate (reciprocal of pulse interval) and so triggered more vagal slowing and feelings of calm. These findings need to now be tested in the clinical setting since, if confirmed, this would greatly simplify the practical use of this promising tool.

Amyloid positron emission tomography with 18F-flutemetamol and structural magnetic resonance imaging in the classification of mild cognitive impairment and Alzheimer’s disease

ObjectiveTo evaluate the contributions of amyloid-positive (Am+) and medial temporal atrophy–positive (MTA+) scans to the diagnostic classification of prodromal and probable Alzheimer’s disease (AD). Methods18F-flutemetamol-labeled amyloid positron emission tomography (PET) and magnetic resonance imaging (MRI) were used to classify 10 young normal, 15 elderly normal, 20 amnestic mild cognitive impairment (aMCI), and 27 AD subjects. MTA+ status was determined using a cut point derived from a previous study, and Am+ status was determined using a conservative and liberal cut point. ResultsThe rates of MRI scans with positive results among young normal, elderly normal, aMCI, and AD subjects were 0%, 20%, 75%, and 82%, respectively. Using conservative cut points, the rates of Am+ scans for these same groups of subjects were 0%, 7%, 50%, and 93%, respectively, with the aMCI group showing the largest discrepancy between Am+ and MTA+ scans. Among aMCI cases, 80% of Am+ subjects were also MTA+, and 70% of amyloid-negative (Am−) subjects were MTA+. The combination of amyloid PET and MTA data was additive, with an overall correct classification rate for aMCI of 86%, when a liberal cut point (standard uptake value ratio = 1.4) was used for amyloid positivity. Interpretation18F-flutemetamol PET and structural MRI provided additive information in the diagnostic classification of aMCI subjects, suggesting an amyloid-independent neurodegenerative component among aMCI subjects in this sample.

Soft Tissue Cephalometric Norms for Orthognathic and Cosmetic Surgery

Proportionality of the lower and middle thirds of the face is a key determinant of successful orthognathic treatment. A flatter profile and marked variance of the soft tissue envelope in the Japanese population complicates the accurate assessment of these proportions. This study aimed to identify gender differences and establish norms for Japanese young adults using the method of soft tissue cephalometric analysis (STCA) by Arnett et al (Am J Orthod Dentofacial Orthop 116:239, 1999). Lateral cephalograms of 49 young normal Japanese subjects (19 men, 30 women) were selected from the archival records and analyzed with STCA. The Student t test was used to compare mean values of the male and female groups. Significant differences were found between women and men. Men had a flatter occlusal plane and a more acute nasolabial angle than women. Men showed larger values for upper and lower lip thickness, menton soft tissue thickness, and vertical face length, especially in the lower third of the face. Women had a more projected midface than men. Compared with established STCA norms, the Japanese have more midfacial projection. Significant gender differences were found in the thickness, lower third length, and midface projection in Japanese young adults, which should be taken into account when interpreting measurements for orthognathic surgical planning. These differences can serve as norms for STCA in young Japanese adults. Differences were noted between the reference values of Arnett et al and Japanese subjects.

Relationship between optic disc ovality and horizontal disc tilt in normal young subjects

To investigate the relationship between optic disc ovality and horizontal disc tilt. The ovality index (the ratio of minimum to maximum disc diameter), horizontal and vertical optic disc tilt, and optic disc torsion were measured on the Heidelberg Retina Tomograph 3 printout in 381 right eyes of 381 normal young subjects. Stereophotographically obvious horizontal tilt and the relationship between the ovality index and horizontal tilt were determined in non-torted discs with an absolute value of disc torsion ≤15°. The median values of the ovality index, horizontal and vertical tilt, and disc torsion in all subjects were 0.92, 9.0°, 0.0°, and 0.0°, respectively. In the non-torted discs (205 eyes, 53.8 %), a horizontal tilt of ≥20° was stereoscopically obvious. The ovality index was significantly correlated with horizontal tilt (r = -0.276, P < 0.001). The area under the receiver operation curve for the ovality index to discriminate a disc with a horizontal tilt of ≥20° was 0.861. The horizontal disc tilt was significantly correlated with spherical equivalent (r = -0.369, P < 0.001) and axial length (r = 0.277, P < 0.001), but the ovality index was not. Although the ovality index may be an indicator of stereoscopically obvious horizontal disc tilt, horizontal tilt is more closely related with myopia.

Brain structures associated with executive functions during everyday events in a non-clinical sample

Executive functions involve control processes such as goal-oriented planning, flexible strategy generation, sustaining set maintenance, self-monitoring, and inhibition. Executive functions during everyday events (EFEEs) are distinct from those measured under laboratory settings; the former can be severely impaired while the latter remain intact. Non-routine everyday problems due to executive dysfunctions affect individual functioning in everyday life and are of great clinical interest. Despite the importance of anatomical bases underlying better EFEEs, such bases have never been investigated among non-clinical samples. Using voxel-based morphometry to measure regional gray matter volume (rGMV) and regional white matter volume (rWMV) and diffusion tensor imaging to determine fractional anisotropy values, we identified the anatomical correlates of better EFEEs using the Dysexecutive Questionnaire in 303 normal young subjects (168 men and 135 women). Better EFEEs were associated with a smaller rGMV in the orbitofrontal cortex (OFC) spread across Brodmann areas (BA) 25, 11, and 12 and larger rWMV in the WM area of OFC adjacent to BA 11. Furthermore, individual EFEEs were positively associated with rWMV in the temporal areas, primarily the inferior longitudinal fasciculus and inferior fronto-occipital fasciculus, the latter of which connects OFC and posterior regions. Thus, our findings suggest that brain structures involving OFC, together with other regions, contribute to the maintenance of effective EFEEs among non-clinical subjects.