Mice in social conflict show rule-observance behavior enhancing long-term benefit.

Disorderly resolution of conflict is costly, whereas orderly resolution by consent rules enables quick settlement. However, it is unclear whether non-human animals can make and observe rules to resolve conflict without aggression. Here we report a new behavioral paradigm for mice: a modified two-armed maze that uses wireless electrical brain stimulation as reward. First, the mice were individually operant-trained to initiate and then receive the reward at the signaled arm. Next, two mice were coupled and had to cooperate to initiate reward but then to compete over reward allocation. Mice develop and observe a rule of reward zone allocation that increases the total amount of reward and reward equity between the pair. In the mutual rule-observance behavior, positive reciprocity and tolerance to the other's violation are also observed. These findings suggest that rodents can learn to make and observe rules to resolve conflict, enhancing long-term benefit and payoff equity.

Acupuncture on GB34 activates the precentral gyrus and prefrontal cortex in Parkinson's disease.

BACKGROUND: Acupuncture is increasingly used as an additional treatment for patients with Parkinson's disease (PD). METHODS: In this functional magnetic resonance imaging study, brain activation in response to acupuncture in a group of 12 patients with PD was compared with a group of 12 healthy participants. Acupuncture was conducted on a specific acupoint, the right GB 34 (Yanglingquan), which is a frequently used acupoint for motor function treatment in the oriental medical field. RESULTS: Acupuncture stimulation on this acupoint activates the prefrontal cortex, precentral gyrus, and putamen in patients with PD; areas that are known to be impaired in patients with PD. Compared with healthy participants, patients with PD showed significantly higher brain activity in the prefrontal cortex and precentral gyrus, especially visible in the left hemisphere. CONCLUSIONS: The neuroimaging results of our study suggest that in future acupuncture research; the prefrontal cortex as well as the precentral gyrus should be treated for symptoms of Parkinson's disease and that GB 34 seems to be a suitable acupoint. Moreover, acupuncture evoked different brain activations in patients with Parkinson's disease than in healthy participants in our study, stressing the importance of conducting acupuncture studies on both healthy participants as well as patients within the same study, in order to detect acupuncture efficacy. TRIAL REGISTRATION: KCT0001122 at cris.nih.go.kr (registration date: 20140530).

Decreased and increased cerebral regional homogeneity in early Parkinson's disease.

Regional homogeneity (ReHo), a processed data from resting-state functional magnetic resonance imaging, provides information about spontaneous brain activity in focal areas. Altered ReHo in brain regions has been reported in Parkinson's disease (PD). We compared ReHo of 22 patients with PD in their off-medication state to 25 healthy controls. We observed decreased ReHo in the right primary sensory cortex, the right primary motor cortex and the right middle frontal gyrus in PD patients. Conversely, ReHo was increased in the left inferior parietal lobule, the angular gyrus, the supramarginal gyrus, the middle occipital gyrus and the parahippocampal gyrus. In the right primary sensory cortex, ReHo showed a positive association with disease duration which proposed the low level of ReHo in the early phase of PD. ReHo was decreased in the seven de novo PD patients with disease duration less than 1 year as compared to the control which corresponded to the prediction. In both the off-medication and de novo PD patients, ReHo decreased in the right primary sensory cortex and increased in the angular gyrus as compared to the control. Potential regression of ReHo extrapolated backwards to PD-onset may provide a clue for 'premotor diagnosis'.

Neural pathway interference by retained acupuncture: a functional MRI study of a dog model of Parkinson's disease.

OBJECTIVE: The aims of this study were to investigate the interference of the brain activation during a passive movement task (PMT) by retained acupuncture at the ST 36 acupoint and to compare these effects between normal brain and Parkinson's disease (PD) brain. METHODS: Functional magnetic resonance imaging (fMRI) techniques have been used to study neurophysiology in animals. Eight healthy beagle dogs were divided into two groups of four dogs each, a normal control group and a PD model group. PD was induced by intravenous injection of 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-HCl. During fMRI, the PMT was performed in the right tarsal joint during three different sessions, which consisted of PMT only, PMT while an acupuncture needle was inserted at the ST 36 acupoint, and PMT while needle was inserted at a sham point. RESULTS AND DISCUSSION: Standard veterinary neurological examination was performed on dogs with MPTP-induced PD. A homogeneous grade similar to human PD patients was evident in all dogs. The fMRI study showed that insertion of the acupuncture needle at acupoint ST 36 significantly affected the proprioceptive brain activation by decreasing blood oxygenation level-dependent signal intensity in basal ganglia, limbic system, and cerebellum. Compared with normal and PD brain, we suggest that acupuncture at ST 36 has different modulation effects depending on the pathologic condition of the brain. The study provides evidence of the potential clinical applications of retained acupuncture at ST 36 for rehabilitation therapy of PD patients.

Acupuncture stimulation on GB34 activates neural responses associated with Parkinson's disease.

BACKGROUND: Parkinson's disease (PD) is a degenerative brain disorder that is caused by neural defects in the substantia nigra. Numerous studies have reported that acupuncture treatment on GB34 (Yanglingquan) leads to significant improvements in patients with PD and in PD animal models. Studies using functional magnetic resonance imaging (fMRI) have shown that patients with PD, compared to healthy participants, have lower neural responses in extensive brain regions including the putamen, thalamus, and the supplementary motor area. OBJECTIVE: This study investigated the reported association between acupuncture point GB34 and PD. METHODS: Using fMRI, neural responses of 12 patients with PD and 12 healthy participants were examined before and after acupuncture stimulation. RESULTS: Acupuncture stimulation increased neural responses in regions including the substantia nigra, caudate, thalamus, and putamen, which are impaired caused by PD. CONCLUSIONS: Areas associated with PD were activated by the acupuncture stimulation on GB34. This shows that acupuncture treatment on GB34 may be effective in improving the symptoms of PD. Although more randomized controlled trials on the topic will be needed, this study shows that acupuncture may be helpful in the treatment of symptoms involving PD.

Sex differences in amygdala subregions: evidence from subregional shape analysis.

Each subregion of the amygdala is characterized by a distinct cytoarchitecture and function. However, most previous studies on sexual dimorphism and aging have assessed differences in the structure of the amygdala at the level of the amygdala in its entirety rather than at the subregional level. Using an amygdala subregional shape analysis, we investigated the effects of sex, age, and the sex × age interaction on the subregion after controlling for intracranial volume. We found the main effect of age in the subregions and the effect of sex in the superficial nucleus, which showed that men had a larger mean radius than women. We also found a sex × age interaction in the centromedial nucleus, in that the radius of the centromedial nucleus showed a steeper decline with age in women compared with men. Regarding the amygdala volume as a whole, we found only an age effect and did not find any other significant difference between genders. The sex difference in the amygdala subregion and its relevance to the circulating gonadal hormone were discussed.

Consecutive acupuncture stimulations lead to significantly decreased neural responses.

OBJECTIVE: Functional magnetic resonance imaging (fMRI), in combination with block design paradigms with consecutive acupuncture stimulations, has often been used to investigate the neural responses to acupuncture. In this study, we investigated whether previous acupuncture stimulations can affect brain activations of later acupuncture stimulations. DESIGN: All subjects were measured twice in the same scanning session and a block design was used. SETTING: The study was conducted at Kyung Hee University, Seoul, Republic of Korea. SUBJECTS: Fifteen (15) healthy right-handed male volunteers participated in the study. INTERVENTION: The subjects received two acupuncture stimulations on BL62 (Shenmai) on the right foot with a time interval of 5 minutes. In addition, sham stimulations were tested with the same paradigm. OUTCOME MEASURES: One-sample t tests were conducted in order to map the brain activations induced by the acupuncture and sham stimulations. Moreover, paired-sample t tests were conducted to investigate the signal changes between the first and second acupuncture stimulation. RESULTS: During the first acupuncture stimulation, in the left hemisphere, significant foci of activation were found in the hypothalamus, thalamus, claustrum, cerebellum, inferior frontal gyrus, and the superior temporal gyrus. In the right hemisphere, a significant focus of activation was found in the middle frontal gyrus. In addition, in both hemispheres, a significant focus of activation was found in the inferior parietal lobule. Interestingly, however, during the second acupuncture stimulation, the only areas that were also significantly activated were the cerebellum in the left hemisphere and the inferior parietal lobule in the right hemisphere. CONCLUSIONS: We found that consecutive acupuncture stimulations on BL62 affected the neural responses in a significant way, resulting in decreased activations during the second acupuncture stimulation. This is an important finding, suggesting that in future fMRI studies on acupuncture, researchers should take this methodological issue more seriously.

Acupuncture inhibits microglial activation and inflammatory events in the MPTP-induced mouse model.

Using a mouse model of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease (PD), this study investigated on the neuroprotective effects of acupuncture by examining whether acupuncture contributed to inhibiting microglial activation and inflammatory events. C57BL/6 mice were treated with MPTP (30 mg/kg, i.p.) for 5 consecutive days. Acupuncture was then applied to acupoints Yanglingquan (GB34) and Taichong (LR3) starting 2 h after the first MPTP administration and then at 48 h intervals until the mice were sacrificed for analyses at 1, 3, and 7 days after the last MPTP injection. These experiments demonstrated that acupuncture inhibited the decreased of the tyrosine hydroxylase (TH) immunoreactivity (IR) and generated a neuroprotective effects in the striatum (ST) and the substantia nigra (SN) on days 1, 3, and 7 post-MPTP injections. Acupuncture attenuated the increase of macrophage antigen complex-1 (MAC-1), a marker of microglial activation, at 1 and 3 days and reduced the increases in cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression on days 1, 3, and 7. In MPTP group, striatal dopamine (DA) was measured by 46% at 7 days, whereas DA in the acupuncture group was 78%. On the basis of these results, we suggest that acupuncture could be used as a neuroprotective intervention for the purpose of inhibiting microglial activation and inflammatory events in PD.

A comparison between directional and proportional methods in locating acupuncture points using dual-energy X-ray absorptiometry in Korean women.

The cun measurement system, an essential and convenient method for locating acupoints, has been widely used in the practice of acupuncture. However, the traditional cun measurement methods have been criticized for their lack of reliability. In addition, new technology has become available to measure the soft tissue and bone mass independently. The present study was conducted in order to determine if one cun, measured by the directional method, is consistent with proportional methods and to investigate whether both methods can be used to locate acupoints. The lengths of bone from several parts of the body in 47 Korean women were measured using Dual-Energy X-ray Absorptiometry. The lengths of each part of the body were compared with 3 cun measured by proportional methods, and the width of all four fingers measured at the level of the proximal inter-phalangeal joint used in the directional method. The results showed that one cun measured by the directional method was significantly different from one cun by proportional methods. The directional method is likely less dependable in locating acupoints than the proportional method.