Therapeutic Effect Evaluation On Soldier's Major Depression Treated By Transcranial Magnetic Stimulation (TMS) And Medicine

Transcranial magnetic stimulation(TMS),a non-invasive means of electrically stimulating neurons in the human cerebral cortex,is able to modify neuronal activity locally and at distant sites when delivered in series or trains of pulses.Data from stimulation of the motor cortex suggest that the type of effect on the excitability of the cortical network depends on the frequency of stimulation.Virtually ever since its adoption as a research tool,observers have wondered whether repetitive transcranial magnetic stimulation(rTMS) could be used to treat brain diseases or improve functional deficits.Early evidence that trains of stimuli delivered to the motor cortex could produce minutes of increased corticospinal hyperexcitability provided the impetus for studies aimed at modulating cortical tone.Small clinical trials soon followed,and the hope of clinicians and the public for non-invasive,medicine-free treatments has sustained this work despite the difficulty of studying an incompletely understood procedure with several dosing parameters,without the benefit of guiding preclinical data,and often without clear hypotheses about the mechanisms of action.1,Major depressionMajor depression is a common disorder with a life time prevalence in the general population of about 13%in men and 21%in women.Despite continuing advances in the development of antidepressant medicines,the condition of about 30%of patients remains refractory to medicine treatment and may require electroconvulsive therapy (ECT).Although ECT as currently practiced is a relatively safe procedure,it nevertheless requires general anesthesia,muscular relaxation and induction of a seizure,and it involves side effects such as memory disturbances.Over the past 9 years,repetitive transcranial magnetic stimulation(rTMS) of the mid-dorsolateral frontal cortex(MDLFC,also described as the dorsolateral prefrontal cortex[PFC]) has been established as a less invasive alternative to ECT.The relevant mechanisms of action are,however,still unknown.At least 2 possibilities exist.First,rTMS may modulate activity in the specific neural circuits(e.g.frontocingulate system) that mediate a given group of symptoms,high frequencies having a facilitatory effect on neural activity while low frequencies produce an inhibitory effect.Second,rTMS effects may be the result of a facilitation of monoaminergic neurotransmission. Numerous studies emphasize that stimulation at different frequencies may have divergent effects on neural activity.Until now,most of these published studies are limited by either open-label design or the use of antidepressant medicines.Concerning the double-blind studies, we observed a lack of homogeneity in the selection criteria of depressive patients and TMS parameters,a short period of treatment by TMS(two weeks in general).Chinese soldiers aged between 18-65,right hander,suffering from unipolar major depressive disorder according to CCMD-3,were recruited in our unit with an HDRS(Hamilton Depression Rating Scale,17 items) Score＞18.They were hospitalized during the first two weeks of the treatment and none were treatment resistant.Patients were randomly assigned to two units,one receiving antidepressant medicines and active rTMS, another receiving medicines and sham rTMS.All the patients gave their written consent before the inclusion in the study.Stimulations were performed over the right dorsolateral prefrontal(DLPF) cortex with a figure 8 coil,and sham TMS was administered over the same point,tilting the coil to an angle of 458 away from the skull.The HDRS was used to assess the severity of depressive symptoms.Statistical comparisons between sham and rTMS treated groups were performed between day 1 versus day 8,day 14,day 28 according to SPSS,the HDRS total score of the medicines combined with rTMS were decreased significantly(P＜0.05),and therapeutic effect were better than medicine with sham rTMS(x~2=11.16,df=1, P=0.0008);medicines combined with rTMS were also better than rTMS single.2,SchizophreniaAuditory hallucinations are experienced by 60-80%of person with schizophrenia and can often cause significant distress behavioral dyscontrol. According to many recent studies using functional magnetic resonance imaging (FMRI),single photon emission computed tomography(SPECT) associated with regional cerebral blood flow(rCBF),positron emission tomography(PET),the left temporoparietal cortex has been implicated in the genesis of auditory hallucinations. Low frequency repetitive transcranial magnetic stimulation(rTMS) can inhibit the excitability of the neuronal,rTMS has been used more successfully to reduce auditory hallucinations in schizophrenia by attempting to reduce excitability in cortical speech processing circuits.In a blinded,sham-controlled study based on localization data from functional neuroimaging.The present study was designed to research the influence of low frequency rTMS on auditory hallucinations patients with schizophrenia,we delivered 1 Hz rTMS at 80%of the MEP threshold to the left temporoparietal cortex in 20 patients with schizophrenia and chronic daily auditory hallucinations,rTMS,particularly longer periods of treatment,reduced auditory hallucinations in most patients that were statistically significant for the group and significantly greater than after sham.Importantly,anticonvulsant medicines appeared to attenuate the therapeutic effect,suggesting that excitation of cortical neurons or synapses by the stimulating current was part of the mechanism.Efficacy was measured using the Positive and Negative Syndrome Scale (PANSS) and Auditory Hallucination Rating Scale(AHRS) at baseline,and at the end of weeks 1 and 2.Mean or median improvement of all but the hallucination scores, however,consistently appeared somewhat better in patients when receiving TMS as opposed to sham TMS(x~2=7.56,P=0.006),patients improved more after the second than the first week.The AHRS scores of the real rTMS were decreased significantly (P＜0.05),but the sham rTMS were not(P＞0.05).The conclusion of this study was low frequency(=1Hz) rTMS could relieve the auditory hallucination of schizophrenic.