Fear conditioning and extinction, which are adaptive processes to learn and avoid potential threats, have essential roles in the pathophysiology of anxiety disorders. Experimental fear conditioning and extinction have been used to identify the mechanism of fear and anxiety in humans. However, the brain-based mechanisms of fear conditioning and extinction are yet to be established. In the current review, we summarized the results of neuroimaging studies that examined the brain changes—functional activity and structures—regarding fear conditioning or extinction in healthy individuals. The functional activity of the amygdala, insula, anterior cingulate gyrus, ventromedial prefrontal cortex, and hippocampus changed dynamically with both fear conditioning and extinction. This review may provide an up-to-date summary that may broaden our understanding of pathophysiological mechanisms of anxiety disorder. In addition, the brain regions that are involved in the fear conditioning and extinction may be considered as potential treatment targets in the future studies.

Repetitive transcranial magnetic stimulation (rTMS) is widely recognized as an effective and noninvasive neuromodulation for treating depression, and has been applied in a wide range of clinical settings. However, previous studies often reported inconsistent antidepressant effects that may be due to differences in the rTMS protocols such as coil placement. The typical simulation site for rTMS depression protocol is the left dorsolateral prefrontal cortex (DLPFC). Targeting the exact site of the left DLPFC while considering individual brain structure has been challenging due to the non-invasive nature of rTMS. Several researchers have applied various targeting methods to overcome the abovementioned issue. Most of the previous studies have applied the “5-cm rule” or the “international 10-20 system,” which is easily applicable. Recently, researchers started to apply a neuronavigation system that targets the stimulation site based on neuroimaging of each individual. Pros and cons of targeting methods have been discussed in terms of validity and reliability of targeting stimulation sites, differences in treatment responses, as well as considerations of individual characteristics. Therefore, the current review focuses on the targeting methods of stimulation site and the treatment effects of depression in previous studies. For discussion, we divided neuronavigation methods into using fixed coordinates and using individualized targets. Furthermore, the limitations of each targeting method are discussed that may potentially contribute to the development of the optimal rTMS protocol for depression treatment.

Mutations in the F-box only protein 7 (FBXO7) gene are the cause of autosomal recessive parkinsonian-pyramidal syndrome. Herein, we report a patient with a novel FBXO7 mutation with a unique clinical presentation. A 43-year-old male visited our hospital with complaints of progressing gait disturbance since a generalized tonic clonic seizure. There were no past neurological symptoms or familial disorders. Neurological examination revealed bradykinesia, masked face, stooped posture, parkinsonian gait, and postural instability. The bilateral uptake by dopamine transporters was nearly abolished, as determined by N-(3-[18F]fluoropropyl)- 2β-carbon ethoxy-3β-(4-iodophenyl) nortropane positron emission tomography (18F-FP-CIT PET). Next-generation sequencing revealed a heterozygous c.1066_1069delTCTG (p.Ser356ArgfsTer56) frameshift variant and a heterozygous c.80G>A (p.Arg27His) missense variant of the FBXO7 gene. The patient’s specific clinical features, medication-refractory parkinsonism and seizures further broaden the spectrum of FBXO7 mutations. The nearly abolished dopamine transporter uptake identified by 18F-FP-CIT PET is frequently found in patients with FBXO7 mutations, which is different from the usual rostrocaudal gradient that is observed in patients with Parkinson’s disease.

Alternating hemiplegia of childhood (AHC) is a rare neurodevelopmental disorder characterized by recurrent paroxysmal hemiplegic attacks that affect one or the other side of the body. Up to 74% of patients with AHC have a pathologic variant in the ATP1A3 gene. After the introduction of next-generation sequencing, intermediate cases and atypical cases have expanded the clinical spectrum of ATP1A3-related disorders. Herein, we report the first case of AHC in Korea. A 33-year-old man visited our hospital with recurrent hemiplegic and dystonic episode after his first birthday. He was completely normal between episodes and did not have any ataxia, but brain magnetic resonance imaging showed cerebellar atrophy. He also had pes planovalgus deformity. Whole exome sequencing revealed a heterozygous G947R variant in the ATP1A3 gene (c.2839G > C, rs398122887), which is a known pathologic variant. This atypical case of AHC demonstrates the importance of the clinical approach in diagnosing ATP1A3-related disorders.

We describe a 44-year-old woman with paresthesia, fatigue, and palpitation, 10 days after human papillomavirus (HPV) vaccination. The quantitative sensory test showed abnormal detection threshold in her foot. Tilt test result indicated postural orthostatic tachycardia syndrome. Symptoms were improved after immunomodulating therapy, pain control drug, and oral beta blocker medication. This is first case report for small fiber neuropathy and autonomic dysfunction after HPV vaccination in Korea.
Adult ; Erythromelalgia ; Fatigue ; Female ; Foot ; Humans ; Korea ; Papillomavirus Vaccines ; Paresthesia ; Postural Orthostatic Tachycardia Syndrome ; Vaccination