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Background: Social dysfunction is a hallmark characteristic of schizophrenia. Part of it may stem from an inability to efficiently encode social information into memory and retrieve it later. This study focused on whether patients with schizophrenia show a memory boost for socially relevant information and engage the same neural network as controls when processing social stimuli that were previously encoded into memory. Methods: Patients with schizophrenia and healthy controls performed a social and nonsocial picture recognition memory task while being scanned. We calculated memory performance using d'. Our main analysis focused on brain activity associated with recognition memory of social and nonsocial pictures. Results: Our study included 28 patients with schizophrenia and 26 controls. Healthy controls demonstrated a memory boost for socially relevant information. In contrast, patients with schizophrenia failed to show enhanced recognition sensitivity for social pictures. At the neural level, patients did not engage the dorsomedial prefrontal cortex (DMPFC) as much as controls while recognizing social pictures. Limitations: Our study did not include direct measures of self- referential processing. All but 3 patients were taking antipsychotic medications, which may have altered both the behavioural performance during the picture recognition memory task and brain activity. Conclusion: Impaired social memory in patients with schizophrenia may be associated with altered DMPFC activity. A reduction of DMPFC activity may reflect less involvement of self-referential processes during memory retrieval. Our functional MRI results contribute to a better mapping of the neural disturbances associated with social memory impairment in patients with schizophrenia and may facilitate the development of innovative treatments, such as transcranial magnetic stimulation., Introduction Individuals who successfully navigate their social world greatly rely on the efficient processing of social cues from the environment. There is accumulating evidence suggesting that social information gains privileged [...]

Transcranial Magnetic Stimulation (TMS) may be the best way to help patients with treatment-resistant major depression (TRMD) -- people who have tried antidepressants once for the appropriate amount of time [...]

When we judge an action as morally right or wrong, we rely on our capacity to infer the actor's mental states (e.g., beliefs, intentions). Here, we test the hypothesis that the right temporoparietal junction (RTPJ), an area involved in mental state reasoning, is necessary for making moral judgments. In two experiments, we used transcranial magnetic stimulation (TMS) to disrupt neural activity in the RTPJ transiently before moral judgment (experiment 1, offline stimulation) and during moral judgment(experiment 2, online stimulation). in both experiments, TMS to the RTPJ led participants to rely less on the actor's mental states. A particularly striking effect occurred for attempted harms (e.g., actors who intended but failed to do harm): Relative to TMS to a control site, TMS to the RTPJ caused participants to judge attempted harms as less morally forbidden and more morally permissible. Thus, interfering with activity in the RTPJ disrupts the capacity to use mental states in moral judgment, especially in the case of attempted harms. functional MRI | morality | theory of mind doi/ 10.1073/pnas.0914826107

Background: Repetitive transcranial magnetic stimulation (rTMS) applied over the dorsolateral prefrontal cortex (DLPFC) is a new treatment procedure that holds promise of more insight into the pathophysiology of depression because the DLPFC may play an important role in the interplay between emotional and attentional information processing. We sought to investigate whether acute neurocognitive effects of rTMS are related to antidepressant outcomes. Methods: Between January 2005 and May 2007, we examined the effects of a single session compared with 2 weeks of rTMS over the left DLPFC on cognition and mood in therapy-resistant patients with depression. We used a crossover placebo-controlled double-blind design and differentiated rTMS treatment responders and nonresponders. We used a task-switching paradigm to measure cognitive function. Results: After 2 weeks of high-frequency rTMS over the left DLPFC, depressive symptoms improved in more than half (53%) of our therapy-resistant population. After a single session, mood did not improve but attentional control was increased solely within our group of treatment responders. Limitations: Our results should be interpreted as preliminary because our sample was small and because the cognitive task we used has not been tested for validity and reliability. In addition, despite minimal stimulation of the DLPFC during sham stimulation, it is possible that the stimulation was partially active. Finally, benzodiazepines may have had impairing effects on the attentional task. Conclusion: Cognitive reactivity after a single session of rTMS may hold promise as a predictor of beneficial treatment outcomes. Moreover, within the group of responders, attentional control appears to play an important role in the progress of mood disorders. Contexte: La stimulation magnetique transcranienne repetitive (SMTr) appliquee au niveau du cortex prefrontal dorsolateral (CPFDL) est une nouvelle modalite therapeutique qui recele la promesse d'un meilleure comprehension de la physiopathologie de la depression, parse que le CPFDL pourrait jouer un role important dans ('interaction entre le traitement de ('information emotionnelle et attentionnelle. Nous avons voulu verifier si les effets neurocognitifs de la SMTr sont lies a des resultats antidepresseurs. Methodes : Entre janvier 2005 et mai 2007, nous avons compare les effets d'une seule seance a ceux de 2 semaines de traitement par SMTr applique au niveau du CPFDL gauche sur la cognition et l'humeur chez des patients depressifs refractaires au traitement. Nous avons utilise un protocole a double insu controle par placebo aver permutation des groupes pour distinguer les participants repondant a la SMTr de ceux n'y repondant pas. Nous avons utilise un paradigme de changement de taches pour mesurer le fonctionnement cognitif. Resultats : Apres 2 semaines de traitement par SMTr a haute frequency, applique au niveau du CPFDL gauche, les symptemes depressifs se sont ameliores chez plus de la moitie (53 %) de notre population refractaire au traitement. Apres une seule seance, l'humeur ne s'est pas amelioree, mais le controle de l'attention avait augmente, et ce, uniquement dans notre groupe repondant au traitement. Limites : Nos resultats doivent titre consideres comme preliminaires puisque notre echantillon etait petit et que la tache cognitive utilisee n'a pas fait ('objet de tests de validite et de fiabilite. En outre, malgre le faible degre de stimulation du CPFDL pendant la stimulation factice, il est possible que cette derniere ait ete partiellement active. En terminant, les benzodiazepines peuvent avoir eu des effets negatifs sur ('execution de la tache attentionnelle. Conclusion : La reactivity cognitive apres une simple seance de SMTr pourrait se reveler prometteuse a titre de predicteur des effets benefiques du traitement. De plus, dans le groupe ayant repondu au traitement, le controle de l'attention semble jouer un role important dans la progression des troubles de l'humeur., Introduction Repetitive transcranial magnetic stimulation (rTMS), a noninvasive method of neuronal depolarization of specific areas of the human brain, is a relatively new technology that holds promise for therapeutic advances [...]

It has been shown that the negative gradient of the component of the electric field, called the activating function, contributes to nerve excitation. In this paper, the induced electric field in a 3-D human head model by transcranial magnetic stimulation (TMS) has been calculated by employing the impedance method. The activating functions are then obtained by gradient operations to the three components of the induced electric field. The activating functions are scattered over the different brain tissues. Peaks of the activating functions are presented at the interfaces of the different tissues. The largest values of the activating functions are presented in the cerebral spinal fluid (CSF). Results in this paper will be beneficial to the TMS applications in clinic as well as in the brain research. Index Terms--Activating function, impedance method, transcranial magnetic stimulation.

Saccadic eye movements cause sudden and global shifts in the retinal image. Rather than causing confusion, however, eye movements expand our sense of space and detail. In macaques, a stable representation of space is embodied by neural populations in intraparietal cortex that redistribute activity with each saccade to compensate for eye displacement, but little is known about equivalent updating mechanisms in humans. We combined noninvasive cortical stimulation with a double-step saccade task to examine the contribution of two human intraparietal areas to transsaccadic spatial updating. Right hemisphere stimulation over the posterior termination of the intraparietal sulcus (IPSp) broadened and shifted the distribution of second-saccade endpoints, but only when the first-saccade was directed into the contralateral hemifield. By interleaving trials with and without cortical stimulation, we show that the shift in endpoints was caused by an enduring effect of stimulation on neural functioning (e.g., modulation of neuronal gain). By varying the onset time of stimulation, we show that the representation of space in IPSp is updated immediately after the first-saccade. In contrast, stimulation of an adjacent IPS site had no such effects on second-saccades. These experiments suggest that stimulation of IPSp distorts an eye position or displacement signal that updates the representation of space at the completion of a saccade. Such sensory-motor integration in IPSp is crucial for the ongoing control of action, and may contribute to visual stability across saccades. coordinate transformations | parietal cortex | spatial representation | transcranial magnetic stimulation | vision

ABSTRACT. One can partially eliminate motor skills acquired through practice in the hours immediately following practice by applying repetitive transcranial stimulation (rTMS) over the primary motor cortex. The disruption of [...]

We have evaluated a multichannel transcranial magnetic stimulation (TMS) system using realistic simulations based on the boundary element method (BEM). We investigated various configurations and types of stimulation coils by means of quantitative measures such as targeting accuracy and field concentration. The simulation studies applied to four different head-brain models suggest improved coil types yielding enhanced targeting accuracy and concentrated evoked electric field distribution. Index Terms--Boundary element method (BEM), magnetic brain stimulation, transcranial magnetic stimulation (TMS).

Objective: Several studies have demonstrated increased left orbitofrontal cortex (OFC) activity during negative and depressed mood. These mood states have also been associated with reduced memory for positive emotional stimuli. [...]

In humans, the primary visual cortex (V1) is essential for conscious vision. However, even without V1 and in the absence of awareness, some preserved ability to accurately respond to visual inputs has been demonstrated, a phenomenon referred to as blindsight. We used transcranial magnetic stimulation (TMS) to deactivate V1, producing transient blindness for visual targets presented in a foveal, TMS-induced scotoma. Despite unawareness of these targets, performance on forced choice discrimination tasks for orientation (experiment 1) and color (experiment 2) were both significantly above chance. In addition to demonstrating that TMS can be successfully used to induce blindsight within a normal population, these results suggest a functioning geniculoextrastriate visual pathway that bypasses V1 and can process orientation and color in the absence of conscious awareness. consciousness | perception | vision | blindsight | transcranial magnetic stimulation

Byline: V. P. Lebedev (1), A. V. Kovalevskii (1), I. V. Gazeeva (1), A. V. Gaisina (1), S. V. Derpgol'ts (1), E. I. Bord (2) Abstract: A randomized single-blind passive placebo-controlled study using a set of seven subjective and objective psychophysiological tests that evaluated the background state and changes in 26 psychophysiological indices (including the physical, cognitive, and affective components of fatigue) showed that transcranial electrostimulation (TES) of endorphinergic structures of the human brain facilitates the normalization of most indices. The positive effects of TES were more pronounced in subjects with strong negative shifts of the initial indices, which suggests a homeostatic character of the effects of activation of the brain endorphin-mediated mechanisms. Special attention was paid to the use of an analog scale for rapid evaluation of fatigue whose validity, reliability, and applicability were proved experimentally by the method of correlation matrices. Author Affiliation: (1) Transcranial Electrostimulation Laboratory, Pavlov Institute of Physiology, Russian Academy of Sciences, St. Petersburg, 199034, Russia (2) Psychoneurological Dispensary no. 1, St. Petersburg, Russia Article History: Registration Date: 16/10/2004

Byline: M. I. Polkey (1), A. Duguet (2), Y. Luo (3), P. D. Hughes (1), N. Hart (1), C.-H. Hamnegard (4), M. Green (1), T. Similowski (2), J. Moxham (3) Keywords: Key words Magnetic stimulation; Phrenic nerves; Diaphragm; Fatigue Abstract: Objective: Anterior magnetic stimulation (aMS) of the phrenic nerves is a new method for the assessment of diaphragm contractility that might have particular applications for the clinical assessment of critically ill patients who are commonly supine. Design: We compared aMS with existing techniques for measurement of diaphragm weakness and fatigue in 10 normal subjects, 27 ambulant patients with suspected diaphragm weakness and 10 critically ill patients. Setting: Laboratory and intensive care unit of two university hospitals. Results: Although aMS was not demonstrably supramaximal in normal subjects, the mean value of twitch transdiaphragmatic pressure (Tw Pdi) obtained at 100 % of stimulator output, 23.7 cm[H.sub.2]O, did not differ significantly from that obtained with bilateral supramaximal electrical stimulation (ES), 24.9 cm[H.sub.2]O, or bilateral anterior magnetic phrenic nerve stimulation (BAMPS), 27.3 cm[H.sub.2]O. A fatiguing protocol produced a 20 % fall in aMS-Tw Pdi and a 19 % fall in BAMPS-Tw Pdi the fall in aMS-Tw Pdi correlated with the fall in BAMPS-Tw Pdi (r .sup.2 = 0.84, p = 0.03) indicating that aMS can detect diaphragm fatigue. In ambulant patients aMS agreed closely with existing measures of diaphragm strength. The maximal sniff Pdi correlated with both the aMS-Tw Pdi (r .sup.2 = 0.60, p < 0.0001) and the BAMPS-Tw Pdi (r .sup.2 = 0.65, p < 0.0001) and the aMS-Tw Pdi was a mean (SD) 2.2 (4.3) cm[H.sub.2]O less than BAMPS-Tw Pdi. In addition, aMS correctly identified diaphragm dysfunction in patients studied on the ICU. Conclusions: We conclude that aMS is of clinical value for the investigation of suspected diaphragm weakness. Author Affiliation: (1) Respiratory Muscle Laboratory, Royal Brompton Hospital, Fulham Rd, London SW3 6NP, UK e-mail: m.polkey@rbh.nthames.nhs.uk Tel. + 44-1 71-3 51 89 39 Fax: + 44-1 71-3 51 80 29, GB (2) Laboratoire de Physiopathologie Respiratoire & Unite de Reanimation, Service de Pneumologie, Groupe Hospitalier Pitie-Salpetriere, Assistance Publique-Hopitaux de Paris and UPRES EA 2379, Universite Paris VI, Paris, France, FR (3) Respiratory Muscle Laboratory, Kings College Hospital, Bessemer Rd, London SE5 9PJ, UK, GB (4) Department of Pulmonary Medicine, Sahlgrenska University Hospital, S-413 45 Goteborg, Sweden, SE Article note: Received: 11 November 1999 Final revision received: 17 April 2000 Accepted: 26 April 2000

Repetitive transcranial magnetic stimulation (rTMS), which allows for direct activation of neurons, will play an ever-expanding role in depression and schizophrenia treatment, according to recent reports from Mark S. George, [...]

Byline: V. P. Kulikov (1), Yu. V. Smirnova (1), K. V. Smirnov (1) Author Affiliation: (1) Altai State Medical University, Barnaul, Russia Article History: Registration Date: 06/10/2004

Byline: P. I. Terekhin (1) Author Affiliation: (1) Russian University of Peoples' Friendship, ul. Miklukho-Maklaya 6, Moscow, 117198, Russia Article History: Registration Date: 06/10/2004