Posterior Cingulate Cortex Area Research Articles

The impact of wearing a KN95 face mask on human brain function: evidence from resting state functional magnetic resonance imaging.

Face masks are widely used in daily life because of the COVID-19 pandemic. The objective of this study was to explore the impact of wearing face masks on brain functions by using resting-state functional MRI (RS-fMRI). Scanning data from 15 healthy subjects (46.20 ± 6.67 years) were collected in this study. Each subject underwent RS-fMRI scans under two comparative conditions, wearing a KN95 mask and natural breathing (no mask). The amplitude of low frequency fluctuation (ALFF) and functional connectivity under the two conditions were analyzed and then compared using the paired t-test. Compared with those of the no-mask condition, the ALFF activities when wearing masks were increased significantly in the right middle frontal gyrus, bilateral precuneus, right superior marginal gyrus, left inferior parietal gyrus, and left supplementary motor area and decreased significantly in the anterior cingulate gyrus, right fusiform gyrus, left superior temporal gyrus, bilateral lingual gyrus, and bilateral calcarine cortex (p < 0.05). Taking the posterior cingulate cortex area as a seed point, the correlations with the occipital cortex, prefrontal lobe, and motor sensory cortex were sensitive to wearing masks compared with not wearing masks (p < 0.05). Taking the medial prefrontal cortex region as a seed point, the functional connectivity with the bilateral temporal lobe, bilateral motor sensory cortex, and occipital lobe was influenced by wearing a KN95 mask (p < 0.05). This study demonstrated that wearing a KN95 face mask can cause short-term changes in human resting brain function. Both local neural activities and functional connectivity in brain regions were sensitive to mask wearing. However, the neural mechanism causing these changes and its impact on cognitive function still need further investigation.

Is Gaucher Disease Type 1 a Neuronopathic Disorder? Neuroradiological and Clinical Findings from Senopro_Gaucher Study

BACKGROUND. Gaucher Disease (GD), an autosomal recessive metabolic disorder due to glucocerebrosidase deficit, includes three clinical phenotypes. GD1 is classically considered as a non-neuronopathic form, in contrast to the GD2 and GD3 forms. The protective role of N370S mutation against neurological impairment has been hypothesized in GD1 patients (pts). However, signs of parkinsonism and/or cognitive impairment and/or behavioural alterations have also been observed in GD1 pts with N370S mutation. Neuroimaging studies indicates that human intellectual ability is related to the brain structure, including cortical thickness (CT) and cortical gyrification (CG), that allows greater cognitive functionality. The prospective SENOPRO_GAUCHER study was planned to evaluate in depth the neurological and neuropsychiatric aspects in GD1 pts, using clinical and instrumental investigations. AIMS. Data from the clinical and instrumental investigations were analyzed in order to a) evaluate the morphological aspects of the cerebral cortex of GD1 pts; b) compare morphological findings in GD1 pts with healthy control subjects (HCs); c) correlate cortical morphological abnormalities, genotypes, neuropsychological and neurological manifestations in GD1 pts. MATHERIALS AND METHODS. Nineteen GD1 pts, aged >12 years (yrs) at the evaluation, were enrolled in the SENOPRO_GAUCHER study. Seventeen of these pts, as well as HCs, matched for age, sex, and education level, underwent a T1-weighted 3Tesla Magnetic Resonance Imaging (MRI) scan to evaluate brain morphometry such as CT and CG in each of the 360 evaluated brain regions (Human Connectome Project parcellation). Pts and HCs had previously undergone neurological and psychological evaluations, including motor parkinsonisms and mental status analysis. RESULTS. All but one of the 17 GD1 pts (M: 5; F: 12; median age 51 yrs) were heterozygous for N370S mutation. Detailed results of the 3T MRI are showed in Table 1 and 2. Thirteen regions of the prefrontal, posterior cingulate and parietal cortex corresponding to the functional domains of the working memory, attention, movement, language, and sensory integration were significantly reduced in CT in 16/17 N370S heterozygous GD1 pts than HCs (p< .05, uncorrected). CT in 5/14 prefrontal and temporo-occipital cortical areas was found lower in 4 pts with cognitive impairment. Greater reduction in CT of the prefrontal areas involved in movement was detected in 7 pts with parkinsonism compared to the HCs. One L444P/V460V pt had an increased CT in 8/14 areas (prefrontal and temporo-occipital cortex). Alterations of CG were found in 6 areas of the frontal, posterior cingulate and temporal cortex. An increased CG in the posterior cingulate cortex areas, corresponding to the functional domains of attention, memory, motor control, sensory integration, and emotional response was detected in all GD1 pts. Moreover, 14/17 pts showed an increase of the frontal regions, corresponding to the functional domains of language, working memory, and movement. CG in a region of the secondary auditory cortex was reduced in GD1 pts greater than in HCs, whereas the CG in prefrontal and frontal regions, cingulate cortex, and inferior temporal gyrus were greater reduced in HCs compared to GD1 pts. Eight out of 16 pts with N370S/other genotype had CG values in 3/6 areas of the prefrontal and temporal cortex similar to those of HCs. Greater CG in 3/6 areas of the prefrontal, temporal and cingulate cortex was found in 4 pts with cognitive impairment. The CG in the frontal superior and cingulate cortex was found greater in 7 pts with parkinsonism signs than in HCs. All 9 symptomatic pts showed reduced CG in the temporo-occipital cortex compared to HCs. CONCLUSIONS. The 3T MRI revealed that all GD1 pts had at least one significant alteration in CT and/or CG in 17/360 cortical regions, specifically in the prefrontal, posterior cingulate and temporo-occipital cortex. The reduction in CT and the increase in CG could be due to a process of brain atrophy. N370S mutation does not seem to be neuroprotective. Functional assessment of the brain areas could help to understand the mechanisms underlying the detected alterations. Additional instrumental and 3T MRI evaluations are planned to evaluate the evolution of cortical alterations and the development of clinical manifestations. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Effect of Anserine/Carnosine Supplementation on Verbal Episodic Memory in Elderly People.

Our goal in this study was to determine whether or not anserine/carnosine supplementation (ACS) is capable of preserving cognitive function of elderly people. In a double-blind randomized controlled trial, volunteers were randomly assigned to an ACS or placebo group at a 1:1 ratio. The ACS group took 1.0 g of an anserine/carnosine (3:1) formula daily for 3 months. Participants were evaluated by psychological tests before and after the 3-month supplementation period. Thirty-nine healthy elderly volunteers (60–78 years old) completed the follow-up tests. Among the tests, delayed recall verbal memory assessed by the Wechsler Memory Scale-Logical Memory showed significant preservation in the ACS group, compared to the placebo group (p = 0.0128). Blood analysis revealed a decreased secretion of inflammatory cytokines, including CCL-2 and IL-8, in the ACS group. MRI analysis using arterial spin labeling showed a suppression in the age-related decline in brain blood flow in the posterior cingulate cortex area in the ACS group, compared to the placebo group (p = 0.0248). In another randomized controlled trial, delayed recall verbal memory showed significant preservation in the ACS group, compared to the placebo group (p = 0.0202). These results collectively suggest that ACS may preserve verbal episodic memory and brain perfusion in elderly people, although further study is needed.

Brain potentials related to self-generated and external information used for performance monitoring

Objective Humans need to supervise and adjust their own behavior by means of an error detection and correction system as well as by using externally available information. The purpose of the present study was to compare the electrophysiological effects related to self-generated internal and to external (feedback) information used for performance monitoring. Methods Fourteen young normal subjects learned to associate each of several line-drawings with either a left-hand or right-hand response. In the experiment proper multi-channel ERPs were obtained time-locked to (a) the line-drawings, (b) the button-press, and (c) subsequent feedback stimuli. Feedback was either affirmative, negative, or equivocal. Event-related potentials were quantified and statistically evaluated using standard methodology. Results Response-locked ERPs showed a typical error-related negativity (ERN) for erroneous responses. ERPs to negative and equivocal feedback stimuli contained a negativity with a more posterior distribution than that of the ERN, which occurred earlier and had a higher peak amplitude in the equivocal condition. Dipole modeling suggests that this feedback-related negativity is generated by medial prefrontal and posterior cingulate cortex areas. Conclusions Different brain systems support the use of internal and external information necessary for performance monitoring and modification. Significance The flexible use of internal and external information for performance control is a core executive function. The delineation of the corresponding brain correlates will further our understanding of executive dysfunction in neurological disorders.