Altered Brain Fraction Amplitude of Low Frequency Fluctuation at Resting State in Patients With Early Left and Right Bell’s Palsy: Do They Have Differences?

Abstract

Purpose: Bell’s palsy refers to acute idiopathic unilateral facial nerve palsy. It is a common disorder of the main motor pathway to the facial muscles. This study aimed to investigate the abnormal fraction amplitude of low frequency fluctuation (fALFF) of the brain in patients with early left and right Bell’s palsy.Materials and Methods: Sixty-seven patients (left 33, right 34) and 37 age- and sex-matched healthy controls underwent resting-state functional magnetic resonance imaging (R-fMRI) examination. The fALFF values were measured from all subjects and were compared among the left palsy, right palsy, and control groups. Then, correlations between the Toronto Facial Grading System (TFGS) scores of the patients and the fALFF values of abnormal brain regions were analyzed.Results: Significant group differences in fALFF values among the three groups were observed mainly in the cerebral cortical, subcortical, and deep gray matter regions. Compared with the right Bell’s palsy group, the left Bell’s palsy group showed significantly decreased fALFF values in the left temporal pole of the superior temporal gyrus (TPOsup), right supramarginal, left and right middle cingulate cortex (MCC), left superior frontal gyrus (SFG), and left precentral gyrus (PreCG), and increased fALFF values were observed in the right SFG and PreCG. Furthermore, altered fALFF values correlated positively with the TFGS scores in the left superior TPO, bilateral MCC, and right PreCG, and correlated negatively with the TFGS scores in the right SFG of the left Bell’s palsy group. Altered fALFF values correlated positively with the TFGS scores in the bilateral MCC and right PreCG and correlated negatively with the TFGS scores in the left superior TPO and SFG of the right Bell’s palsy group.Conclusion: Regulatory mechanisms seem to differ between patients with left and right early Bell’s palsy. The severity of the disease is associated with these functional alterations.

Abnormal Emotional Processing and Emotional Experience in Patients with Peripheral Facial Nerve Paralysis: An MEG Study

“…However, our results are consistent with the result of an earlier study that reported blocking facial mimicry of healthy subjects causes different neural activations in the amygdala in response to emotional stimuli [3]. Our results are also compatible with a very recent study that compared patients with facial nerve paralysis and healthy controls in resting state and found that the brain fraction amplitude of low-frequency fluctuation is abnormal in emotion-related regions [46].…”

Maternal psychological distress associates with alterations in resting‐state low‐frequency fluctuations and distal functional connectivity of the neonate medial prefrontal cortex

“…changes in local and distal FC (Zhou, Shi, et al, 2019; Zhou, Tang, et al, 2019). Alterations, mostly increases, in fALFF values in a spectrum of pathological states (Du et al, 2019; Han et al, 2018; Zeng et al, 2019; Zhou, Tang, et al, 2019) suggest fairly good sensitivity but not necessarily neurobiological specificity. Indeed, abnormalities in cortical fALFF patterns can also be observed in subjects with white matter lesions, such as in Bell's palsy (Han et al, 2018), suggestive of reactive changes of neural firing patterns to altered whole network function.…”

“…Alterations, mostly increases, in fALFF values in a spectrum of pathological states (Du et al, 2019; Han et al, 2018; Zeng et al, 2019; Zhou, Tang, et al, 2019) suggest fairly good sensitivity but not necessarily neurobiological specificity. Indeed, abnormalities in cortical fALFF patterns can also be observed in subjects with white matter lesions, such as in Bell's palsy (Han et al, 2018), suggestive of reactive changes of neural firing patterns to altered whole network function. Furthermore, there are reports of distinct fALFF patterns associating with personality traits in healthy individuals (Ikeda et al, 2017; Wei et al, 2011) and mathematical disability in children (Jolles et al, 2016), advocating an interpretation for fALFF as a nonspecific marker of altered neural activity in a neural population.…”

Differences in functional brain alterations driven by right or left facial nerve efferent dysfunction: Evidence from early Bell’s palsy

“…These regions with altered FC further highlight the differences in functional reorganization activities, mainly involving the emotional processes network in the right palsy group, and motor-related functional integration in the left palsy group, compared to the healthy controls. We speculate that psychological stress and negative emotions are heightened to different degrees in patients with bilateral Bell's palsy, because of their involuntary abnormal facial expressions and movements (30).…”