Computational Evaluation of Combined Cerebellar and Frontal Transcranial Direct Current Stimulation for Treatment-Resistant Depression.

This work aimed to estimate the distribution of the electric field generated by a combined cerebellar and frontal transcranial direct current stimulation (tDCS) for treatment-resistant depression using electromagnetics computational techniques applied to a realistic head human model. Results showed that the stronger electric fields occur mainly in the cerebellum and in DLPFC areas, where the two pairs of electrodes were applied. Furthermore, the study demonstrated that the simultaneous use of the two pairs of electrodes did not imply a lower effectiveness of the tDCS technique, in fact the electric field distributions in the primarily targets of the anatomical regions (i.e., cerebellum and DLPFC) were very similar to when the pairs of electrodes were applied separately.

Consensus Paper: Cerebellum and Emotion.

Over the past three decades, insights into the role of the cerebellum in emotional processing have substantially increased. Indeed, methodological refinements in cerebellar lesion studies and major technological advancements in the field of neuroscience are in particular responsible to an exponential growth of knowledge on the topic. It is timely to review the available data and to critically evaluate the current status of the role of the cerebellum in emotion and related domains. The main aim of this article is to present an overview of current facts and ongoing debates relating to clinical, neuroimaging, and neurophysiological findings on the role of the cerebellum in key aspects of emotion. Experts in the field of cerebellar research discuss the range of cerebellar contributions to emotion in nine topics. Topics include the role of the cerebellum in perception and recognition, forwarding and encoding of emotional information, and the experience and regulation of emotional states in relation to motor, cognitive, and social behaviors. In addition, perspectives including cerebellar involvement in emotional learning, pain, emotional aspects of speech, and neuropsychiatric aspects of the cerebellum in mood disorders are briefly discussed. Results of this consensus paper illustrate how theory and empirical research have converged to produce a composite picture of brain topography, physiology, and function that establishes the role of the cerebellum in many aspects of emotional processing.

Non-invasive cerebellar stimulation--a consensus paper.

The field of neurostimulation of the cerebellum either with transcranial magnetic stimulation (TMS; single pulse or repetitive (rTMS)) or transcranial direct current stimulation (tDCS; anodal or cathodal) is gaining popularity in the scientific community, in particular because these stimulation techniques are non-invasive and provide novel information on cerebellar functions. There is a consensus amongst the panel of experts that both TMS and tDCS can effectively influence cerebellar functions, not only in the motor domain, with effects on visually guided tracking tasks, motor surround inhibition, motor adaptation and learning, but also for the cognitive and affective operations handled by the cerebro-cerebellar circuits. Verbal working memory, semantic associations and predictive language processing are amongst these operations. Both TMS and tDCS modulate the connectivity between the cerebellum and the primary motor cortex, tuning cerebellar excitability. Cerebellar TMS is an effective and valuable method to evaluate the cerebello-thalamo-cortical loop functions and for the study of the pathophysiology of ataxia. In most circumstances, DCS induces a polarity-dependent site-specific modulation of cerebellar activity. Paired associative stimulation of the cerebello-dentato-thalamo-M1 pathway can induce bidirectional long-term spike-timing-dependent plasticity-like changes of corticospinal excitability. However, the panel of experts considers that several important issues still remain unresolved and require further research. In particular, the role of TMS in promoting cerebellar plasticity is not established. Moreover, the exact positioning of electrode stimulation and the duration of the after effects of tDCS remain unclear. Future studies are required to better define how DCS over particular regions of the cerebellum affects individual cerebellar symptoms, given the topographical organization of cerebellar symptoms. The long-term neural consequences of non-invasive cerebellar modulation are also unclear. Although there is an agreement that the clinical applications in cerebellar disorders are likely numerous, it is emphasized that rigorous large-scale clinical trials are missing. Further studies should be encouraged to better clarify the role of using non-invasive neurostimulation techniques over the cerebellum in motor, cognitive and psychiatric rehabilitation strategies.

Computational model of cerebellar transcranial direct current stimulation.

This work aimed to estimate the distribution of the electric field and current density generated by cerebellar tDCS using electromagnetics computational techniques applied to a realistic human models of different ages and gender. Results show that the stronger electric field and current density occur mainly in the cerebellar cortex, with a spread toward the occipital region of the cortex, while the current spread to other structures is negligible. Moreover, changes of about 1 cm in the position of the scalp electrode delivering tDCS did not influence the E and J distribution in the cerebellum.

Lies tell the truth about cognitive dysfunction in essential tremor: an experimental deception study with the guilty knowledge task.

BACKGROUND: Research conducted in the past decade challenges the traditional view that essential tremor (ET) is characterised exclusively by movement disorder, and increasingly shows that these patients have deficits in cognitive and behavioural functioning. The available evidence suggests that this impairment might arise from dysfunction in either the fronto-subcortical or cortico-cerebellar circuits. Although abnormalities in the fronto-subcortical circuits could imply difficulty in lying, no study has investigated deception in patients with ET. AIMS: To examine the cognitive functions regulating deception in patients with ET, we used a computerised task, the Guilty Knowledge Task (GKT). We also tested a group of patients with Parkinson's disease (PD), a disease associated with a known difficulty in lie production, and a group of healthy subjects (HS). RESULTS: In the GKT for deception, patients with ET responded less accurately than HS (p=0.014) but similarly to patients with PD (p=0.955). No differences between groups were found in truthful responses (p=0.488). CONCLUSIONS: Besides confirming impaired deception in patients with PD, our results show a lie production deficit in patients with ET also. These findings suggest that difficulty in lying is an aspecific cognitive feature in movement disorders characterised by fronto-subcortical circuit dysfunction, such as PD and ET. Current knowledge along with our new findings in patients with ET--possibly arising from individually unrecognised extremely mild, cognitive difficulties--should help in designing specific rehabilitative programmes to improve cognitive and behavioural disturbances in patients.

Interactions between transcranial direct current stimulation (tDCS) and pharmacological interventions in the Major Depressive Episode: findings from a naturalistic study.

BACKGROUND: Transcranial direct current stimulation (tDCS) is a non-invasive, neuromodulatory technique with an emerging role for treating major depression. OBJECTIVE: To investigate the interactions between tDCS and drug therapy in unipolar and bipolar depressed patients who were refractory for at least one pharmacological treatment. METHODS: This was a naturalistic study using data from 54 female and 28 male patients (mean age of 54 years) that consecutively visited our psychiatric unit. They received active tDCS (five consecutive days, 2mA, anodal stimulation over the left and cathodal over the right dorsolateral prefrontal cortex, twice a day, 20minutes). The outcome variable (mood) was evaluated using the Beck Depression Inventory (BDI) and the Hamilton Depression Rating Scale (HDRS). Predictor variables were age, gender, disorder and pharmacological treatment (seven dummy variables). We performed univariate and multivariate analyses as to identify predictors associated to the outcome. RESULTS: After 5 days of treatment, BDI and HDRS scores decreased significantly (29%±36%, 18%±9%, respectively, P<0.01 for both). Benzodiazepine use was independently associated with a worse outcome in both univariate (ß=4.92, P<0.01) and multivariate (ß=5.8, P<0.01) analyses; whereas use of dual-reuptake inhibitors positively changed tDCS effects in the multivariate model (ß=-4.7, P=0.02). A similar trend was observed for tricyclics (ß=-4, P=0.06) but not for antipsychotics, non-benzodiazepine anticonvulsants and other drugs. CONCLUSION: tDCS over the DLPFC acutely improved depressive symptoms. Besides the inherent limitations of our naturalistic design, our results suggest that tDCS effects might vary according to prior pharmacological treatment, notably benzodiazepines and some antidepressant classes. This issue should be further explored in controlled studies.

Transcranial direct current stimulation for the outpatient treatment of poor-responder depressed patients.

Transcranial direct current stimulation (tDCS) is a selective, painless, brain stimulation technique that allows the electric stimulation of specific cortical regions. TDCS has been recently used as investigational intervention for major depression and treatment resistant depression (TRD) with encouraging results. The present study was aimed to investigate the efficacy and tolerability of tDCS in major depressives with poor response to pharmacological treatment. Twenty-three depressed patients, with a diagnosis of major depressive disorder or bipolar disorder, were treated with augmentative tDCS for 5 days, two sessions per day in a blind-rater trial. The course of depressive symptoms was analyzed using repeated measures ANOVA for HAM-D and MADRS total scores. A qualitative analysis on the basis of the HAM-D response was performed as well. Both analyses were conducted at three time-points: T0 (baseline), T1 (endpoint tDCS) and T2 (end of the first week of follow-up). All patients completed the trial without relevant side-effects. A significant reduction of HAM-D and MADRS total scores was observed during the study (P<0.0001). Treatment response (endpoint HAM-D reduction ≥50%) was obtained by four patients (17.4%) at T1 and by seven patients (30.4%) at T2 and remission (endpoint HAM-D<8) by three patients (13.0%) at T1 and by four subjects (17.4%) at T2. Present findings support the efficacy and good tolerability of tDCS in the acute treatment of patients with TRD with clinical benefit being progressive and extended to the first week of follow-up. Further sham-controlled trials with longer follow-up are needed to confirm present results.

Transcranial direct current stimulation (tDCS) in unipolar vs. bipolar depressive disorder.

Transcranial direct current stimulation (tDCS) is a non-invasive method for brain stimulation. Although pilot trials have shown that tDCS yields promising results for major depressive disorder (MDD), its efficacy for bipolar depressive disorder (BDD), a condition with high prevalence and poor treatment outcomes, is unknown. In a previous study we explored the effectiveness of tDCS for MDD. Here, we expanded our research, recruiting patients with MDD and BDD. We enrolled 31 hospitalized patients (24 women) aged 30-70 years 17 with MDD and 14 with BDD (n = 14). All patients received stable drug regimens for at least two weeks before enrollment and drug dosages remained unchanged throughout the study. We applied tDCS over the dorsolateral prefrontal cortex (anodal electrode on the left and cathodal on the right) using a 2 mA-current for 20 min, twice-daily, for 5 consecutive days. Depression was measured at baseline, after 5 tDCS sessions, one week later, and one month after treatment onset. We used the scales of Beck (BDI) and Hamilton-21 items (HDRS). All patients tolerated treatment well without adverse effects. After the fifth tDCS session, depressive symptoms in both study groups diminished, and the beneficial effect persisted at one week and one month. In conclusion, our preliminary study suggests that tDCS is a promising treatment for patients with MDD and BDD.2.

Gender-related differences in moral judgments.

The moral sense is among the most complex aspects of the human mind. Despite substantial evidence confirming gender-related neurobiological and behavioral differences, and psychological research suggesting gender specificities in moral development, whether these differences arise from cultural effects or are innate remains unclear. In this study, we investigated the role of gender, education (general education and health education) and religious belief (Catholic and non-Catholic) on moral choices by testing 50 men and 50 women with a moral judgment task. Whereas we found no differences between the two genders in utilitarian responses to non-moral dilemmas and to impersonal moral dilemmas, men gave significantly more utilitarian answers to personal moral (PM) dilemmas (i.e., those courses of action whose endorsement involves highly emotional decisions). Cultural factors such as education and religion had no effect on performance in the moral judgment task. These findings suggest that the cognitive-emotional processes involved in evaluating PM dilemmas differ in men and in women, possibly reflecting differences in the underlying neural mechanisms. Gender-related determinants of moral behavior may partly explain gender differences in real-life involving power management, economic decision-making, leadership and possibly also aggressive and criminal behaviors.

Transcranial direct current stimulation in severe, drug-resistant major depression.

BACKGROUND: Though antidepressant drugs are the treatment of choice for severe major depression, a number of patients do not improve with pharmacologic treatment. This study aimed to assess the effects of transcranial direct current stimulation (tDCS) in patients with severe, drug-resistant depression. METHODS: Fourteen hospitalized patients aged 37-68, with severe major depressive disorder according to DSM-IV.TR criteria, drug resistant, with high risk of suicide and referred for ECT were included. Mood was evaluated using the Beck Depression Inventory (BDI), the Hamilton Depression Rating Scale (HDRS) and the Visual Analogue Scale (VAS). We also administered cognitive tasks to evaluate the possible cognitive effects on memory and attention. tDCS was delivered over the dorsolateral prefrontal cortex (DLPC) (2 mA, 20 min, anode left, cathode right) twice a day. RESULTS: After five days of treatment although cognitive performances remained unchanged, the BDI and HDRS scores improved more than 30% (BDI p=0.001; HDRS p=0.017). The mood improvement persisted and even increased at four (T2) weeks after treatment ended. The feeling of sadness and mood as evaluated by VAS improved after tDCS (Sadness p=0.007; Mood p=0.036). CONCLUSIONS: We conclude that frontal tDCS is a simple, promising technique that can be considered in clinical practice as adjuvant treatment for hospitalized patients with severe, drug-resistant major depression.

Transcranial direct current stimulation improves recognition memory in Alzheimer disease.

OBJECTIVE: To evaluate the cognitive effect of transcranial direct current stimulation (tDCS) over the temporoparietal areas in patients with Alzheimer disease (AD). METHODS: In 10 patients with probable AD, we delivered anodal tDCS (AtDCS), cathodal tDCS (CtDCS), and sham tDCS (StDCS) over the temporoparietal areas in three sessions. In each session recognition memory and visual attention were tested at baseline (prestimulation) and 30 minutes after tDCS ended (poststimulation). RESULTS: After AtDCS, accuracy of the word recognition memory task increased (prestimulation: 15.5 +/- 0.9, poststimulation: 17.9 +/- 0.8, p = 0.0068) whereas after CtDCS it decreased (15.8 +/- 0.6 vs 13.2 +/- 0.9, p = 0.011) and after StDCS it remained unchanged (16.3 +/- 0.7 vs 16.0 +/- 1.0, p = 0.75). tDCS left the visual attention-reaction times unchanged. CONCLUSION: Transcranial direct current stimulation (tDCS) delivered over the temporoparietal areas can specifically affect a recognition memory performance in patients with Alzheimer disease (AD). Because tDCS is simple, safe and inexpensive, our finding prompts studies using repeated tDCS, in conjunction with other therapeutic interventions for treating patients with AD.

Cerebellar transcranial direct current stimulation impairs the practice-dependent proficiency increase in working memory.

How the cerebellum is involved in the practice and proficiency of non-motor functions is still unclear. We tested whether transcranial direct current stimulation (tDCS) over the cerebellum (cerebellar tDCS) induces after-effects on the practice-dependent increase in the proficiency of a working memory (WM) task (Sternberg test) in 13 healthy subjects. We also assessed the effects of cerebellar tDCS on visual evoked potentials (VEPs) in four subjects and compared the effects of cerebellar tDCS on the Sternberg test with those elicited by tDCS delivered over the prefrontal cortex in five subjects. Our experiments showed that anodal or cathodal tDCS over the cerebellum impaired the practice-dependent improvement in the reaction times in a WM task. Because tDCS delivered over the prefrontal cortex induced an immediate change in the WM task but left the practice-dependent proficiency unchanged, the effects of cerebellar tDCS are structure-specific. Cerebellar tDCS left VEPs unaffected, its effect on the Sternberg task therefore seems unlikely to arise from visual system involvement. In conclusion, tDCS over the cerebellum specifically impairs the practice-dependent proficiency increase in verbal WM.

Improved naming after transcranial direct current stimulation in aphasia.

Transcranial direct current stimulation (tDCS) has been proposed as an adjuvant technique to improve functional recovery after ischaemic stroke. This study evaluated the effect of tDCS over the left frontotemporal areas in eight chronic non-fluent post-stroke aphasic patients. The protocol consisted of the assessment of picture naming (accuracy and response time) before and immediately after anodal or cathodal tDCS (2 mA, 10 minutes) and sham stimulation. Whereas anodal tDCS and sham tDCS failed to induce any changes, cathodal tDCS significantly improved the accuracy of the picture naming task by a mean of 33.6% (SEM 13.8%).

Lie-specific involvement of dorsolateral prefrontal cortex in deception.

Lies are intentional distortions of event knowledge. No experimental data are available on manipulating lying processes. To address this issue, we stimulated the dorsolateral prefrontal cortex (DLPFC) using transcranial direct current stimulation (tDCS). Fifteen healthy volunteers were tested before and after tDCS (anodal, cathodal, and sham). Two types of truthful (truthful selected: TS; truthful unselected: TU) and deceptive (lie selected: LS; lie unselected: LU) responses were evaluated using a computer-controlled task. Reaction times (RTs) and accuracy were collected and used as dependent variables. In the baseline task, the RT was significantly longer for lie responses than for true responses ([mean +/- standard error] 1153.4 +/- 42.0 ms vs. 1039.6 +/- 36.6 ms; F(1,14) = 27.25, P = 0.00013). At baseline, RT for selected pictures was significantly shorter than RT for unselected pictures (1051.26 +/- 39.0 ms vs. 1141.76 +/- 41.1 ms; F(1,14) = 34.85, P = 0.00004). Whereas after cathodal and sham stimulation, lie responses remained unchanged (cathodal 5.26 +/- 2.7%; sham 5.66 +/- 3.6%), after anodal tDCS, RTs significantly increased but did so only for LS responses (16.86 +/- 5.0%; P = 0.002). These findings show that manipulation of brain function with DLPFC tDCS specifically influences experimental deception and that distinctive neural mechanisms underlie different types of lies.

[Health status of women at work: work risks and living conditions]. / La salute delle donne al lavoro: interferenze tra rischi lavorativi e condizioni di vita.

The increase of women at work calls for a new attention to a full health protection, besides the fertility and reproduction. Health Surveillance in workplaces can give much information about health state of women and men, when the evaluation takes into account physiological and social differences between the sexes. The study reports the health data from a working population, 675 women and 7991 men, employed in different work activities. The results showed no significant difference of health state between women and men, except a greater prevalence of the respiratory pathologies in men and psychosomatic disorders in women. Prevalence of muscle-skeletal diseases, psychosomatic disorders and recurring headache have been higher in married than in unmarried women. among married women, prevalence of pathologies have been related to number of children. No difference have been found between unmarried and married men, except a greater prevalence of psychic disorders in youngest. Results confirm the interaction between domestic and working load on health state of women. Under the same work conditions, women are subjected to a higher physical and mental load that reduces the endurance of strain and stress and increases the prevalence of some pathologies, as musculoskeletal chronic degenerative diseases and psychological disorders.

[Chronic-degenerative diseases in health care activities: data from health surveillance of Federico II University General Hospital in Naples]. / Patologie cronico-degenerative nelle attività assistenziali: i dati nell'Azienda Ospedaliera Universitaria Federico II di Napoli.

Recent average life increase, as well as new habits and lifestyles assumption, has determined a change in population health profiles, as a result of progressive increase in chronic-degenerative diseases prevalence. Among these latter; musculoskeletal and cardiovascular diseases are the most frequent ones. Health care workers also suffered from this change in health profiles. This study, performed thanks to the extension of Health Surveillance to all health care workers, aimed at evaluating chronic-degenerative diseases risk among three main welfare activities (medical, nursing and auxiliary). In conclusion, data showed that nurses, mainly the shift workers, are exposed to a higher risk of chronic-degenerative diseases. All other health care workers have not significant work risk factors, because of a greater burden of aging and lifestyles effects.

[Burden of COPD on health profiles in different work activities]. / La broncopatia cronico-ostruttiva nella popolazione generale e in popolazioni lavorative.

According to WHO, COPD will be the 5th cause of disability and the 3rd cause of mortality by 2020. Even cigarette smoking represents the main cause of COPD recent studies demonstrated positive association with occupational exposure. In Europe costs of COPD were estimated at about 38,8 billion Euros in 2000; its burden is also expected to increase. Aim of the study is to evaluate the burden of COPD on health profiles in a sample of workers of Campania region. Prevalences were calculated in a sample of 908 male workers, employed in industrial (479) and tertiary (429) sectors. Results were compared with population data of ISTAT database. Higher prevalence of COPD was found in industrial workers (23.4%) than general population (3.5%) and tertiary workers (2.1%). Analysing smoking habits, higher prevalence of smokers in the industrial sector (75.9%) than tertiary (66.4%) was found, but this difference cannot explain the big difference of COPD prevalence between the two groups and suggest a positive interaction between smoking and occupational exposure. In conclusion, the results analysis underlines the burden of COPD on workers' health status, particularly in some work activities. Specific health promotion programs are necessary in these activities.

[Not allergic dermatitis as occupational diseases: a suggestion for an evaluation method]. / La definizione della professionalità delle dermatiti non allergiche: proposta di un metodo di valutazione.

Aim of the study was to propose a method to define the relationship of not allergic contact dermatitis with chemical risk factors in workplace. This method evaluates the skin response to simultaneous chemical and mechanical stimulation, made with a soft bristle brush. The method has been used on 9 cases of not allergic skin diseases, observed from 2000 to 2006 in Occupational Medicine Division of "Federico II" University of Naples. The greatest part of pathologies had the polymorphous pattern of skin inflammation, characterized by subintrant erythema, suspected of occupational origin. In 6 cases a stronger reaction to both chemical and mechanical stimulation was highlighted, confirming a possible occupational etiology. In 1 case the occupational origin was excluded, while in 2 cases the skin response was uncertain. The method does not define all cases of occupational skin pathologies, but it seems to be very useful to diagnostic and insurance needs.