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IntroductionDisorders of consciousness (DoC) from severe brain injuries have significant impacts. However, further research on nuanced biomarkers is needed to fully understand the condition. This study employed resting-state functional MRI (rs-fMRI) and the amplitude of low-frequency fluctuation (ALFF) to investigate differential brain activity in patients with DoC following spinal cord stimulation (SCS) therapy. It also assessed the predictive value of rs-fMRI and ALFF in determining the consciousness levels at 3 months post-therapy.MethodsWe analyzed rs-fMRI data from 31 patients with traumatic brain injury (TBI) and 22 with non-traumatic brain injury (non-TBI) diagnosed with DoC. ALFF was measured before SCS therapy, and clinical outcomes were assessed 3 months later using the Coma Recovery Scale-Revised.ResultsPatients with TBI showed increased ALFF in the thalamus and anterior cingulate cortex, whereas the middle occipital lobe showed decreased ALFF. In the non-TBI group, a higher ALFF was noted in the precuneus, with a reduced ALFF in the occipital and temporal lobes. Patients with improved consciousness post-SCS exhibited distinct ALFF patterns compared with those with unchanged consciousness, particularly in the posterior cingulate and occipital regions.ConclusionThe application of ALFF in rs-fMRI may be a predictive tool for post-treatment outcomes in patients with DoC of varying etiologies. Differential ALFF in specific brain regions could indicate the likelihood of improvement in consciousness following SCS therapy.Clinical trial registrationhttps://www.chictr.org.cn/, Identifier ChiCTR2300069756.

Approximately 7% of COVID-19 patients (1.3% children) have exhibited symptoms of post-acute sequelae of SARS-CoV-2 infection (PASC), or Long COVID, and 20% of those present with neuropsychiatric symptoms. While a large number of MRI-based neuroimaging studies in this population have shown cortical atrophy in terms of gray matter volume and cortical thickness in patients, there is a growing body of work showing brain volume enlargements or thickness increases in patients compared to COVID negative controls. To investigate this further, we used structural magnetic resonance imaging (MRI) to examine differences in gray matter thickness for the cortical limbic and the dorsolateral prefrontal cortical regions between patients with Long COVID and healthy controls. Results showed increased cortical thickness in the caudal anterior, isthmus, and the posterior cingulate gyrus as well as the rostral middle frontal gyrus respectively along with higher gray matter volume in the posterior cingulate and the isthmus cingulate in patients with Long COVID. Cortical thickness and gray matter volumes for regions of interest (ROIs) were also associated with the severity measures, clinical dementia rating, and anxiety scores in the Long COVID group. Our findings provide supporting evidence for cortical hypertrophy in Long COVID.

Abstract Background and objectives The cingulate gyrus (CG) is a frequently studied yet not wholly understood area of the human cerebrum. Previous studies have implicated CG in different adaptive cognitive–emotional functions and fascinating or debilitating symptoms. We describe an unusual loss of gravity perception/floating sensation in consecutive persons with drug-resistant epilepsy undergoing electrical cortical stimulation (ECS), network analysis, and network robustness mapping. Methods Using Intracranial–EEG, Granger causality analysis, cortico-cortical evoked potentials, and fMRI, we explicate the functional networks arising from this phenomenon's anterior, middle, and posterior cingulate cortex. Results Fifty-four icEEG cases from 2013 to 2019 were screened. In 40.7% of cases, CG was sampled and in 22.2% the sampling was bilateral. ECS mapping was carried out in 18.5% of the entire cohort and 45.4% of the cingulate sampled cases. Five of the ten CG cases experienced symptoms during stimulation. A total of 1942 electrodes were implanted with a median number of 182 electrode contacts per patient (range: 106–274). The electrode contacts sampled all major cortex regions. Sixty-three contacts were within CG. Of those, 26 were electrically stimulated; 53.8% of the stimulated contacts produced positive responses, whereas 46.2% produced no observable responses. Our study reports a unique perceptive phenomenon of a subjective sense of weightlessness/floating sensation triggered by anterior and posterior CG stimulation, in 30% of cases and 21.42% of electrode stimulation sites. Notable findings include functional connections between the insula, the posterior and anterior cingulate cortex, and networks between the middle cingulate and the frontal and temporal lobes and the cerebellum. We also postulate a vestibular–cerebral–cingulate network responsible for the perception of gravity while suggesting that cingulate functional connectivity follows a long-term developmental trajectory as indicated by a robust, positive correlation with age and the extent of Granger connectivity (r = 0.82, p = 0.0035). Discussion We propose, in conjunction with ECS techniques, that a better understanding of the underlying gravity perception networks can lead to promising neuromodulatory clinical applications. Classification of evidence This study provides Class II evidence for CG's involvement in the higher order processing of gravity perception and related actions.

The spontaneous changes in brain activity in patients with diabetic optic neuropathy using steady-state fMRI. The fractional amplitude of the low-frequency fluctuation method was applied to evaluate neural activity changes. The Hospital Anxiety and Depression Scale was used to assess the anxiety and depression status of participants. The independent sample t-test and chi-squared test were applied to analyze the demographics of diabetic optic neuropathy patients and healthy controls. Receiver operating characteristic curves were applied to analyze the variation in mean fractional amplitude of low-frequency fluctuation values between diabetic optic neuropathy patients and healthy controls. Pearson’s correlation analysis analyzed the relationships between the fractional amplitude of low-frequency fluctuation values of brain regions and clinical behaviors in the diabetic optic neuropathy group. The fractional amplitude of low-frequency fluctuation value of diabetic optic neuropathy patients was significantly higher than healthy controls in the right precentral gyrus. However, the fractional amplitude of low-frequency fluctuation values in the right anterior cingulate gyrus and left middle cingulate gyrus were markedly decreased in diabetic optic neuropathy patients. The area under the curve of receiver operating characteristics for each brain region showed high accuracy. Pearson’s correlation analysis showed that fractional amplitude of low-frequency fluctuation values of the right anterior cingulate gyrus and left middle cingulate gyrus was negatively correlated with Hospital Anxiety and Depression Scale scores. The fractional amplitude of low-frequency fluctuation values of the left middle cingulate gyrus was negatively correlated with diabetic optic neuropathy disease duration. In conclusion, we found abnormal spontaneous brain activities in regions related to cognitive and emotional dysfunction, eye movement disorder, and vision loss in patients with diabetic optic neuropathy. These results may indicate the underlying neuropathological mechanisms of diabetic optic neuropathy and show that fractional amplitude of low-frequency fluctuation may be an effective method to distinguish patients with diabetic optic neuropathy from healthy individuals.

Some surgical failures after temporal lobe epilepsy surgery may be due to the presence of an extratemporal epileptogenic zone. Of particular interest is the medial parietal lobe due to its robust connectivity with mesial temporal structures. Seizures in that area may be clinically silent before propagating to the symptomatogenic temporal lobe. In this paper, we present an overview of the anatomical connectivity, semiology, radiology, electroencephalography, neuropsychology, and outcomes in medial parietal lobe epilepsy. We also present two illustrative cases of seizures originating from the precuneus and the posterior cingulate cortex. We conclude that the medial parietal lobe should be strongly considered for sampling by intracranial electrodes in individuals with nonlesional temporal lobe epilepsy, especially if scrutinizing the presurgical data produces discordant findings.

Xiaoyaosan (XYS), as a classic Chinese medicine compound, has been proven to have antidepressant effect in many studies, but its mechanism has not been clarified. In our previous studies, we found that chronic stress can induce depressive-like behavior and lead to emotion-related cingulate gyrus (Cg) dysfunction, as well as the decrease of neurotrophic factors and the increase of inflammatory-related proteins. Therefore, we speculated that XYS may play an antidepressant role by regulating the inflammation-related receptor of advanced glycation protein end product (RAGE) to affect the functional connectivity (FC) signal of the Cg and improve the depressive-like behavior. In order to verify this hypothesis, we analyzed the FC and RAGE expression in the Cg of depressive-like mice induced by chronic unpredictable mild stress (CUMS) and verified it with RAGE knockout mice. At the same time, we detected the effect of XYS on the depressive-like behavior, expression of RAGE, and the FC of the Cg of mice. The results showed that the FC of the Cg of depressive-like mice induced by CUMS was weakened, and the expression of RAGE was upregulated. The antidepressant effect of XYS is similar to that of fluoxetine hydrochloride, which can significantly reduce the depressive-like behavior of mice and inhibit the expression of the RAGE protein and mRNA in the Cg, and increase the FC of the Cg in mice. In conclusion, XYS may play an antidepressant role by downregulating the expression of RAGE in the Cg of depressive-like mice induced by CUMS, thereby affecting the functional signal and improving the depressive-like behavior.

Just as the human brain works in a Bayesian manner to minimize uncertainty regarding external stimuli, a deafferented brain due to hearing loss attempts to obtain or “fill in” the missing auditory information, resulting in auditory phantom percepts (i.e., tinnitus). Among various types of hearing loss, sudden sensorineural hearing loss (SSNHL) has been extensively reported to be associated with tinnitus. However, the reason that tinnitus develops selectively in some patients with SSNHL remains elusive, which led us to hypothesize that patients with SSNHL with tinnitus (SSNHL-T) and those without tinnitus (SSNHL-NT) may exhibit different cortical activity patterns. In the current study, we compared resting-state quantitative electroencephalography findings between 13 SSNHL-T and 13 SSNHL-NT subjects strictly matched for demographic characteristics and hearing thresholds. By performing whole-brain source localization analysis complemented by functional connectivity analysis, we aimed to determine the as-yet-unidentified cortical oscillatory signatures that may reveal potential prerequisites for the perception of tinnitus in patients with SSNHL. Compared with the SSNHL-NT group, the SSNHL-T group showed significantly higher cortical activity in Bayesian inferential network areas such as the frontopolar cortex, orbitofrontal cortex (OFC), and pregenual anterior cingulate cortex (pgACC) for the beta 3 and gamma frequency bands. This suggests that tinnitus develops in a brain with sudden auditory deafferentation only if the Bayesian inferential network updates the missing auditory information and the pgACC-based top-down gatekeeper system is actively involved. Additionally, significantly increased connectivity between the OFC and precuneus for the gamma frequency band was observed in the SSNHL-T group, further suggesting that tinnitus derived from Bayesian inference may be linked to the default mode network so that tinnitus is regarded as normal. Taken together, our preliminary results suggest a possible mechanism for the selective development of tinnitus in patients with SSNHL. Also, these areas could serve as the potential targets of neuromodulatory approaches to preventing the development or prolonged perception of tinnitus in subjects with SSNHL.

The cingulum bundle (CB) connects gray matter structures of the limbic system and as such has been implicated in the etiology of schizophrenia. There is growing evidence to suggest that the CB is actually comprised of a conglomeration of discrete sub-connections. The present study aimed to use Diffusion Tensor tractography to subdivide the CB into its constituent sub-connections, and to investigate the structural integrity of these sub-connections in patients with schizophrenia and matched healthy controls. Diffusion Tensor Imaging scans were acquired from 24 patients diagnosed with chronic schizophrenia and 26 matched healthy controls. Deterministic tractography was used in conjunction with FreeSurfer-based regions-of-interest to subdivide the CB into 5 sub-connections (I1 to I5). The patients with schizophrenia exhibited subnormal levels of FA in two cingulum sub-connections, specifically the fibers connecting the rostral and caudal anterior cingulate gyrus (I1) and the fibers connecting the isthmus of the cingulate with the parahippocampal cortex (I4). Furthermore, while FA in the I1 sub-connection was correlated with the severity of patients' positive symptoms (specifically hallucinations and delusions), FA in the I4 sub-connection was correlated with the severity of patients' negative symptoms (specifically affective flattening and anhedonia/asociality). These results support the notion that the CB is a conglomeration of structurally interconnected yet functionally distinct sub-connections, of which only a subset are abnormal in patients with schizophrenia. Furthermore, while acknowledging the fact that the present study only investigated the CB, these results suggest that the positive and negative symptoms of schizophrenia may have distinct neurobiological underpinnings.

This study presents data from a magnetic-resonance morphometric (MRMM) analysisof the main regions of the cingulate cortex (in both hemispheres) and theirrole in memory processes in a group of healthy, females of older age. The resultsdemonstrate a statistically reliable correlation between overall performance andthe type of errors in different neuropsychological memory tests and the relativesize of these regions. The discovered pattern of correlations can be explained byhypothesizing the reciprocal functional influence of the two major areas of thecingulate cortex – its anterior and posterior dorsal parts – on performance in neuropsychologicalmemory tests.

We present the case of a 13-year-old child with nocturnal frontal lobe epilepsy (NFLE) related to a right cingulate gyrus cortical dysplasia, who also presented with psychogenic nonepileptic seizures (PNES) and interictal antisocial behavior. The association of drug-resistant epilepsy with behavioral disorders is well established, but the role of epilepsy surgery in these patients is still controversial, especially in children. The key finding is represented by the excellent long-term outcome on both epilepsy and behavioral dysfunction after the surgical excision of the cingulate gyrus cortical dysplasia.

The nucleus accumbens (NA) and the cingulate gyrus (CG) are two vital limbic brain structures. They have attracted attention as deep brain stimulation (DBS) targets in the treatment of common refractory psychiatric illness. The primary purpose of this article was to review the current knowledge regarding the way that NA DBS affects the CG and vice versa. Methodologically, a thorough literature review was performed. According to the current literature, NA DBS modulates the function of several brain areas including the CG cortex. It specifically causes activation in the ipsilateral CG cortex and voltage-dependent reduction of its blood oxygenation. It also reverses anterior mid-CG cortex dysfunction and decreases metabolism in the subgenual CG. Moreover, NA DBS that induces mirth inhibits the function of the anterior CG cortex and enhances effective connectivity from anterior CG to the ventral striatum. On the other hand, although it is highly probable that CG DBS affects the NA, the exact nature of its effects remains unclear. Despite the increasing interest in psychiatric DBS, the available data on how NA DBS affects the CG and vice versa are restricted. This conclusion probably reflects the high complexity of the limbic circuits and necessitates further research.

Objectives: The aim of the present study was to use a voxel-based MRI method to investigate the neuroanatomical characteristics in subjects at high risk of developing psychosis compared with those of healthy controls and first-episode schizophrenia patients. Methods: This study included 14 subjects with at-risk mental state (ARMS), 34 patients with first-episode schizophrenia, and 51 healthy controls. We used voxel-based morphometry (VBM) with the Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra (DARTEL) tools to investigate the whole-brain difference in gray matter volume among the three groups. Results: Compared with the healthy controls, the schizophrenia patients showed significant gray matter reduction in the left anterior cingulate gyrus. There was no significant difference in the gray matter volume between the ARMS and other groups. Conclusion: The present study suggests that alteration of the anterior cingulate gyrus may be associated with development of frank psychosis. Further studies with a larger ARMS subjects would be required to examine the potential role of neuroimaging methods in the prediction of future transition into psychosis.

Haemodynamic changes associated with epileptic activity were investigated at Christian-Albrechts-University, Kiel, Germany, using simultaneous acquisitions of EEG and functional MRI in 12 children with symptomatic and cryptogenic continuous spikes and waves during slow sleep (CSWSS).