Page 9 - JCBP-3-4

Journal of Clinical and
Basic Psychosomatics Neuroimaging of bipolar disorder and self-stigma

target for transcranial magnetic stimulation therapy. 2.2. Research progress of MRS in BD
Wang et al. found a decrease in functional connectivity MRS is a non-invasive method for measuring the levels of
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between the right posterior cerebellar lobe and right different neurometabolites in the brain. Current studies
posterior cingulate gyrus in BD patients during remission, have suggested alterations in the levels of N-acetylaspartate
suggesting a compensatory role of the cerebellum in (NAA), myoinositol (mI), Cho, creatine (Cr), Glu,
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emotion regulation. In addition, Saleem et al. found glutamine (Gln), and Glu+Gln (Glx) in various brain
that changes in functional connectivity between the regions of patients with BD. 28
cerebellar vermis and the left posterior ventral thalamus,
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as well as the right anterior parahippocampal gyrus, were In the prefrontal cortex (PFC), Gupta et al. conducted
negatively correlated with scores on standard depression studies on the dorsolateral PFC and hippocampus,
scales. They also found that the functional connectivity and they discovered that NAA levels were lower in the
between the cerebellar vermis and the left middle frontal left dorsolateral PFC of patients with BD in remission.
In addition, they discovered that inositol levels in the
gyrus was negatively correlated with scores on the Young dorsolateral PFC, as well as the Glx and mI levels in the
Mania Rating Scale. Ultimately, the emotional differences
observed in BD patients may be due to differential hippocampus, were higher than those in the control
group. These changes in neurometabolite levels may be
compensation by the cerebellar vermis in various brain associated with cognitive impairment in patients. They
regions related to emotion. The aforementioned studies also investigated the neurometabolism in the vmPFC
suggest that the strength of functional connectivity among of adolescents with bipolar depression accompanied by
the thalamus, cerebral cortex, and cerebellum may be anxiety. They found that the mI/Cr ratio in the vmPFC
related to cognitive function, suicide risk, and emotion was higher in the group with anxiety symptoms than in
regulation in BD patients. the group without anxiety symptoms. Another study on
Gao et al. found that BD patients with manic episodes impulsive aggressive behavior in adolescents with bipolar
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exhibited decreased network homogeneity in the right depression found that the NAA/Cr ratio was lower in the
inferior parietal lobule compared to BD patients in group with impulsive aggressive behavior than in the group
remission. Furthermore, the network homogeneity values without impulsive aggressive behavior. 30,31 In studies of
of the right inferior parietal lobule could distinguish BD prefrontal white matter (PWM), it was found that Glu levels
patients with manic episodes from those in remission. were significantly elevated in bilateral ventral PWM, and
Zhang et al. conducted a study comparing functional Cho compound levels were significantly elevated in the left
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connectivity in pediatric patients diagnosed with either ventral PWM of BD patients. Moore et al. observed that
pediatric BD first-episode depressive (PBD-FED) or Glx levels were higher in BD patients during remission than
pediatric BD first-episode manic (PBD-FEM). In the study, during manic episodes. These changes in neurometabolites
they found that PBD-FEM patients exhibited enhanced may be related to the phases of BD patients.
activation in the medial temporal lobe and decreased In the ACC, studies have shown that Glu/Cr and
activation in the ACC within the salience network Glx/Cr levels were elevated in patients with BD during
compared to PBD-FED patients. In the limbic network, remission. Scotti-Muzzi et al. found that the Glu/
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PBD-FED patients showed lower activation in the gamma-aminobutyric acid ratio decreased in BD patients
bilateral hippocampi compared to the PBD-FEM patients, during remission, which may be related to factors such
which may account for differences in memory function. as the use of anticonvulsants and antipsychotics. Soeiro
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Furthermore, when compared to the PBD-FEM patients, et al. studied BD patients who regularly use lithium and
PBD-FED patients demonstrated decreased activation in found that after achieving emotional stability with regular
the bilateral angular gyrus and increased activation in the lithium treatment, the Cho/Cr and mI/Cr ratios in these
medial precuneus and posterior cingulate cortex within the patients decreased to levels comparable to those of healthy
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default mode network, with the posterior cingulate cortex controls. Similarly, Kong et al. also observed significantly
particularly linked to attentional functions and working elevated Cho and Glu levels, along with a significant
memory. In addition, within the PBD-FEM group, a decrease in NAA, in the ACC of BD patients who had not
significant positive correlation was observed between the taken medication recently. These changes may be related
left inferior parietal lobule and manic scores, which may be to the neurotoxicity in BD patients, caused by factors such
related to manic episodes being the initial onset symptom as brain cell damage, accelerated phospholipid cycling, or
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of BD. These research findings provide neuroimaging increased glutamatergic neurotransmission.
evidence for the differences among BD patients at different In the cerebellar vermis, basal ganglia, and thalamus,
stages (Table 1). Magnotta et al. reported that the levels of Glu and NAA in
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Volume 3 Issue 4 (2025) 3 doi: 10.36922/jcbp.8413