Abnormal functional connectivities patterns of multidomain cognitive impairments in pontine stroke patients

Abstract

Cognitive dysfunction in patients with infratentorial stroke has been paid little attention. Brainstem stroke may disrupt network connectivity across the whole brain and affect multidomain cognition, but the details of this process remain unclear. The study aimed to investigate the effects of stroke‐induced pontine injury on whole‐brain network connectivity and cognitive function. We included 47 patients with pontine stroke and 56 healthy comparisons (HC), who underwent cognitive tests and functional magnetic resonance imaging (fMRI). Seven meaningful brain networks were identified using independent component analysis (ICA). Patients with pontine stroke had decreased intra‐network functional connectivities (FCs) in the primary perceptual and higher cognitive control networks, including sensorimotor network (SMN), visual network (VIS), default mode network (DMN), and salience network (SAN), as well as decreased inter‐network FCs in the primary perceptual (VIS‐SMN) and higher cognitive control networks (bilateral frontoparietal networks, rFPN‐lFPN). While the FCs between the primary perceptual and higher cognitive control networks (VIS‐DMN, VIS‐rFPN, VIS‐lFPN) were increased. Furthermore, the alterations in these FCs correlated with patients' cognitive measurements. These findings suggested that the infratentorial stroke can induce dysfunctional connectivity in both primary perceptual and higher cognitive control networks at the whole‐brain level, which may be attributable to the neural substrates of multidomain cognitive deficits in these patients.

Dynamic brain activity states of memory impairment in stroke patients with varying motor outcomes

“…These observations suggest that a subcortical stroke can trigger imbalances between the segregation and integration of spatiotemporal patterns of neural activity within the whole brain network. This finding is consistent with prior neuroimaging studies based on function and structure connection, which demonstrated that dysfunction induced by the subcortical stroke involves multiple-domain functional networks (Wang et al, 2014(Wang et al, , 2021(Wang et al, , 2022. The regions of advanced cognitive control network (i.e., FN) are responsible for externally directed higher-order cognitive function and diverse demanding tasks, such as guiding fine motor function (Liang et al, 2016;Wen et al, 2018).…”

“…By examining the dynamic changes in the ALFF, we can gain insights into the dynamic characteristics of brain activity and its relationship with various cognitive processes and neurological disorders. Previous studies have demonstrated that patients with stroke exhibit dynamic alterations in spontaneous neural activity across multiple brain networks (Guo et al, 2019;Ma et al, 2021;Wang et al, 2022), indicating the potential utility of dynamic local metrics as predictive tools for functional outcomes in stroke patients. This dynamic attribute emphasizes the materiality of an intact neuroanatomical connectome in facilitating effective information exchange among interconnected regions.…”

Alterations in intra- and inter-network connectivity associated with cognition impairment in insulinoma patients

“…In the presented study, we found a decrease in connectivity in the occipital region within the VN in patients with insulinoma. The VN is located bilaterally in the occipital cortex and extends into the temporo-occipital junction ( 52 ), which plays a primary role in visual information processing ( 53 ). This finding here reflects an underlying visual dysfunction in insulinoma patients, which is consistent with previous studies.…”

Fronto–Cerebellar Diaschisis and Cognitive Dysfunction after Pontine Stroke: A Case Series and Systematic Review

“…Wang et al compared a set of neuropsychological results between 47 pontine stroke patients and 55 age-matched healthy control subjects. The pons lesion group had a significantly weakened executive function, working memory, and spatial memory relative to the healthy control group [ 48 ]. Fu et al compared neuropsychological data between 34 brainstem stroke patients and a healthy control group.…”

“…In favor of this view, SPECT scans detected cerebral perfusion abnormalities or decreases in the regional cerebral blood flow in remote brain regions after a brainstem stroke [ 20 , 22 , 23 , 39 , 40 ]. Intriguingly, the injury is followed by morphological and degenerative changes in the brain, such as frontal and thalamic volume expansions or cerebellar atrophy [ 41 , 42 , 43 , 44 ], anterograde and retrograde degeneration in the corticospinal tracts [ 45 , 46 , 47 ], and aberrant functional connectivity [ 48 , 49 , 50 ].…”