Encephalitis that primarily involves limbic system structures such as the hippocampus and parahippocampal gyrus has been described in early papers, most commonly characterized by a subacute progressive impairment of short-term memory, psychiatric features and seizures. While these findings might be caused by viral infections or systemic autoimmune disorders, many patients with limbic encephalitis have an immune-mediated etiology (paraneoplastic or not) characterized with serum or CSF antineuronal antibodies. This case reports about non-paraneoplastic autoantibody-negative limbic encephalitis in which there are no detection of antigens and no evidence of tumors.
Antibodies ; Encephalitis ; Hippocampus ; Humans ; Limbic Encephalitis* ; Limbic System ; Memory* ; Memory, Short-Term ; Parahippocampal Gyrus ; Seizures

To investigate the functions of the amygdala in limbic system, changes in heart rate and body temperature resulting from electrical destructions of amygdala centralis and piriform cortex were observed in a total of 40 rats varying in weight from 180 to 250g with the use of stereotaxic apparatus(Reyniers and Sons). The results were as follows; 1) Bilateral destructions of amygdala centralis revealed a tendency to increased heart rate and decreased rectal temperature. 2) Bilateral destructions of piriform cortex revealed no changes in heart rate and rectal temperature. Therefore, it is assumed that cardiovascular and temperature responses are not significantly resulted from the electrical destructions of amygdala centralis and piriform cortex.
Amygdala ; Animals ; Body Temperature ; Heart Rate ; Limbic System ; Rats

According to the Jastreboff's neurophysiological model of tinnitus, if negative associations are attached to the tinnitus signal, tinnitus is perceived to be a threat or a danger and it activates the autonomic nervous and limbic systems. Consequently patient's awareness of tinnitus is heightened and so patient perceives it to be louder and more persistent. Jastreboff and Hazell started tinnitus retraining therapy (TRT) based on the neurophysiological model of tinnitus. The purpose of TRT is blocking tinnitus from activating the sympathetic nervous and limbic systems (habituation of reaction) and from reaching the cerebral cortex (habituation of perception). TRT is composed of two components directive counseling that tries to reclassify tinnitus into the meaningless stimuli and sound therapy that decreases the relative strength of the tinnitus signal. Physicians try to put patient's tinnitus into the territory of meaningless stimuli through retraining the brain (habituation of reaction). Because the brain habituates all unimportant stimuli, if habituation of reaction is fully achieved, habituation of perception will follow automatically. In most clinical results, clinical success rates of TRT approach or exceed 80% improvement. Early improvement can be achieved during the first few months, followed by additional progressive improvement. It should be recommended that the patient continue treatment at least 18 months.
Brain ; Cerebral Cortex ; Directive Counseling ; Humans ; Limbic System ; Tinnitus*

OBJECTIVES: To investigate the effects of (-)-3-PPP(0.5, 2, and 10mg/kg, s.c.) and haloperidol(0.1, 0.5, and 2mg/kg, s.c.) on the extracellular dopamine concentrations, and the effect of pretreatment with (-)-3-PPP(2mg/kg) on the haloperidol(2mg/kg)-induced extracellular dopamine concentrations in the nucleus accumbens(NAS) of free moving rats. METHODS: Dopamine levels in dialysate were determined with high pressure liquid chromatography(HPLC) with electrochemical detection(ECD). RESULTS: (1) (-)-3-PPP had dual actions depending on the doses : at 2mg/kg, it decreased and at 10mg/kg, increased extracellular dopamine concentrations ; (2) haloperidol at all doses increased dopamine levels with higher dose having a greater icrease ; and (3) pretreatment of (-)-3-PPP reduced the increase in dopamine levels elicited by acute treatment with haloperidol. CONCLUSIONS: These findings suggest that pretreatment of (-)-3-PPP in low dose could accelerate the onset of therapeutic effect of haloperidol by diminishing the haloperidol-induced dopamine release in the limbic system.
Animals ; Dopamine* ; Haloperidol ; Limbic System ; Nucleus Accumbens* ; Rats*

Autoimmune encephalitis is a group of disorders that predominantly affects the limbic system, with or without an associated neoplasm. Recently GABAB receptor antibody has been identified in a subset of encephalitides. We report a case of anti-GABAB receptor antibody encephalitis in a 64-year-old woman, who presented with transient, recurrent abnormal behavior and complex partial seizures. She had a history of breast cancer, which was in complete remission and her workup, including blood, imaging and routine cerebrospinal fluid studies was unremarkable. Indirect immunofluorescence assays with patient's serum revealed the presence of autoantibodies against GABAB receptor. She showed significant improvement after initiating immunotherapy. This case illustrates the importance of autoantibody testing in the diagnosis of encephalitis.
Autoantibodies ; Brain Diseases ; Breast Neoplasms ; Encephalitis ; Female ; Fluorescent Antibody Technique, Indirect ; Hashimoto Disease ; Humans ; Immunotherapy ; Limbic Encephalitis ; Limbic System ; Seizures

OBJECTIVE: The gyrus rectus (GR) is known as a non-functional gyrus; hence, its resection is agreed to be a safe procedure frequently practiced to achieve a better surgical view during specific surgeries. This study aimed at comparing the cognitive outcomes following GR resection in patients who underwent surgery for ruptured anterior communicating artery (ACoA) aneurysms. MATERIALS AND METHODS: From 2012 to 2015, 39 patients underwent surgical clipping for ruptured ACoA aneurysms. Mini-mental state examinations (MMSE) were performed in 2 different periods. The statistical relationship between GR resection and MMSE results was evaluated, and further analysis of MMSE subgroup was performed. RESULTS: Twenty-five out of the 39 patients (64.19%) underwent GR resection. Mean initial and final MMSE scores in the GR resection group were 16.3 ± 9.8 and 20.8 ± 7.3, respectively. In the non-resection group, the mean initial and final MMSE scores were 17.1 ± 8.6 and 21.9 ± 4.5, respectively. Neither group's scores showed a significant change. Subgroup analysis of initial MMSE showed a significant difference in memory recall and language (p = 0.02) but not in the final MMSE scores. CONCLUSION: There was no significant relationship between the GR resection and cognitive outcomes in terms of total MMSE scores after surgery for ruptured ACoA aneurysm. However, subgroup analysis revealed a temporary negative effect of GR resection in the categories of language and memory recall. This study suggests that GR resection should be executed superficially, owing to its close anatomical relationship with the limbic system.
Aneurysm ; Arteries ; Cognition Disorders* ; Humans ; Intracranial Aneurysm* ; Limbic System ; Memory ; Prefrontal Cortex* ; Surgical Instruments

OBJECTIVE: The aim of this study is to investigate abnormal findings of social brain network in Korean children with autism spectrum disorder (ASD) compared with typically developing children (TDC). METHODS: Functional magnetic resonance imaging (fMRI) was performed to examine brain activations during the processing of emotional faces (happy, fearful, and neutral) in 17 children with ASD, 24 TDC. RESULTS: When emotional face stimuli were given to children with ASD, various areas of the social brain relevant to social cognition showed reduced activation. Specifically, ASD children exhibited less activation in the right amygdala (AMY), right superior temporal sulcus (STS) and right inferior frontal gyrus (IFG) than TDC group when fearful faces were shown. Activation of left insular cortex and right IFG in response to happy faces was less in the ASD group. Similar findings were also found in left superior insular gyrus and right insula in case of neutral stimulation. CONCLUSION: These findings suggest that children with ASD have different processing of social and emotional experience at the neural level. In other words, the deficit of social cognition in ASD could be explained by the deterioration of the capacity for visual analysis of emotional faces, the subsequent inner imitation through mirror neuron system (MNS), and the ability to transmit it to the limbic system and to process the transmitted emotion.
Amygdala ; Brain* ; Autism Spectrum Disorder* ; Child* ; Cognition ; Humans ; Limbic System ; Magnetic Resonance Imaging* ; Mirror Neurons

Amisulpride, a substituted benzamide derivative, is a newer atypical antipsychotics. It mainly blocks presynaptic dopamine D2/D3 autoreceptors which is preferentially located in prefrontal area and blocks postsynaptic dopamine D2/D3 receptors in the limbic system. By these mechanism, amisulpride can improve both negative and positive symptoms. In addition to these action, its property of fast dissociation (Koff) and selectivity to D2/D3 receptors can explain more favorable side effects profiles. A lot of studies showed that amisulpride has equivalent or better efficacy and safety to other atypical antipsychotics. Meta-analysis studies is very informative because it contains many cases of previous studies. So we reviewed some meta-analysis studies which compared amisulpride with placebo or other antipsychotics. On positive symptoms of acute schizophrenia, the most pooled analyses of amisulpride have shown to be equally effective with conventional antispychotics. One meta-analysis study have shown that amisulpride is more effective than conventional drugs. On primary negative symptoms, amisulpride is only agents which is investigated for the efficacy in patients with predominantly negative symptoms. as a results of meta-analysis, amisulpride was shown to be more effective than placebo in primary negative symptoms and have a trend of superiority to conventional agents. The safety and tolerability of amisulpride was equal to or better than other atypical drugs on pooled analysis. The drop out rate was also more favorable than conventional antipsychotics. In Summary, amisulpride showed efficacy similar to that of other atypical antipsychotics in reducing positive symptoms. Moreover, its better properties for negative and affective symptoms, and favorable side effects profiles provides another alternative for treatment of schizophrenia. These results show that amisulpride is a favorable `atypical' antipsychotics, and that 5-HT2/D2 antagonism is not only mechanism of `atypicality'.
Affective Symptoms ; Antipsychotic Agents ; Autoreceptors ; Dopamine ; Humans ; Limbic System ; Meta-Analysis as Topic ; Schizophrenia

BACKGROUND AND PURPOSE: The association between the low emotional regulation and the brain structural change of major depressive disorder (MDD) has been proposed, but the voxel-based morphometry (VBM) studies on female MDD are rare. The purpose of the present study was to show the regional volume changes of gray matter (GM) in female patients with MDD by optimized VBM. METHODS: To control subjects homogeneity, twenty female MDD patients and age, sex matched 21 normal controls were included for the VBM analysis. To identify the change of regional gray matter volume (GMV), the optimized VBM was performed with T1 MRIs. The amounts of gray/white matter and intracranial cavity volumes (ICV) were measured. The analysis of covariance (ANCOVA) and partial correlation analyses covariate with age and ICV were applied for VBM. RESULTS: The age and ICV distributions were similar between the two groups. In the ANCOVA, the total GMV of MDD was smaller than that of normal controls. In the VBM, regional GMV was relatively decreased in the limbic system (amygdalae, ambient gyri, hippocampi heads, subiculum, posterior parahippocampal gyri, pulvinar nuclei, dorsal posterior cingulate gyri, and left pregenual cingulate gyrus). The lingual gyri, short insular gyri, right fusiform gyrus, and right inferior frontal gyrus were also showed decreased regional GMV. CONCLUSION: The results of this study indicate that the female MDD is mainly associated with the structural deficits of the limbic system and limbic system related cortices, which were known to the center of emotions.
Brain ; Depressive Disorder, Major* ; Female ; Head ; Hippocampus ; Humans ; Limbic System ; Magnetic Resonance Imaging ; Pulvinar

BACKGROUND: Although olfactory stimulation has been known to produce effects on human mood and cognition, the specific EEG patterns of activity was reported diversely. The purpose of this study was to investigate EEG changes by odorant using low resolution electromagnetic tomography (LORETA) in young healthy subjects. METHODS: The EEG's of nineteen (10 males, 9 females) non-smoking right-handed college students were recorded after odorant stimulation. A nineteen-channel EEG was recorded referenced to linked ears before and during olfactory stimulation. Olfactory stimulation was presented with lavender essential oil by blotter method. The LORETA power was computed from ten 2-s epochs, separately for the different EEG frequencies. The power values were logarithmically transformed and paired sample t-tests were done for each voxel and frequency band (1.5-30 Hz). Statistical results were displayed 3-dimensionally on the standard brain template. RESULTS: All subjects experienced positive feelings (relaxed and pleasant) by olfactory stimulation with lavender oil (p<0.01). The LORETA power of theta and alpha band was increased in the dorsolateral and medial frontal areas, predominantly in the posterior cingulate gyri. The alpha LORETA power was also increased in bilateral orbitofrontal regions and the left perisylvian region including the insular cortex. Beta power was increased in the posterior cingulated gyri and mesial temporal region, predominantly on the left side. CONCLUSIONS: These results suggest that olfaction associated with emotional feeling might induce brain electrical power changes not only in the limbic system but also in the neocortex with lateralization to the dominant hemisphere.
Brain ; Cognition ; Ear ; Electroencephalography ; Humans ; Lavandula ; Limbic System ; Magnets ; Male ; Neocortex ; Odors* ; Smell