Motor imagery in spinal cord injured people is modulated by somatotopic coding, perspective taking, and post-lesional chronic pain.

Motor imagery (MI) allows one to mentally represent an action without necessarily performing it. Importantly, however, MI is profoundly influenced by the ability to actually execute actions, as demonstrated by the impairment of this ability as a consequence of lesions in motor cortices, limb amputations, movement limiting chronic pain, and spinal cord injury. Understanding MI and its deficits in patients with motor limitations is fundamentally important as development of some brain-computer interfaces and daily life strategies for coping with motor disorders are based on this ability. We explored MI in a large sample of patients with spinal cord injury (SCI) using a comprehensive battery of questionnaires to assess the ability to imagine actions from a first-person or a third-person perspective and also imagine the proprioceptive components of actions. Moreover, we correlated MI skills with personality measures and clinical variables such as the level and completeness of the lesion and the presence of chronic pain. We found that the MI deficits (1) concerned the body parts affected by deafferentation and deefferentation, (2) were present in first- but not in third-person perspectives, and (3) were more altered in the presence of chronic pain. MI is thus closely related to bodily perceptions and representations. Every attempt to devise tools and trainings aimed at improving autonomy needs to consider the cognitive changes due to the body-brain disconnection.

Interactions Between Body and Social Awareness in Yoga.

BACKGROUND/OBJECTIVE: Bodily processes have been intimately linked to social-cognitive and affective functions, such as compassion and empathy. Yet, little is known about how awareness of bodily processes influences social awareness and vice versa, especially in nonobservational but experiential investigations. This study investigated the relationship between psychometrically reported body and social awareness (including altruism, empathy, perspective-taking, and compassion) in 90 yoga and yoga-/mediation-naive control participants. In modern postural yoga, advanced practitioners claim both increased compassion and inner focus. METHODS: Multiple regression analyses were conducted to predict (1) the level of yoga practice from body awareness and social awareness skills in the yoga group and (2) body awareness from social skills in both groups. RESULTS: Body awareness and compassion were significant positive and independent predictors of yoga expertise. This finding supports practitioners' anecdotal claims but also implies that both functions tap into different aspects of yoga expertise. When body awareness was predicted, altruism emerged as a significant negative predictor in the yoga group (but not control group) as a function of yoga practice. CONCLUSION: These results might compellingly suggest that, despite high compassion, heightened bodily self-awareness might increase a self-centred perspective and limit altruistic acts in advanced yoga practitioners.

Virtual lesions of the inferior parietal cortex induce fast changes of implicit religiousness/spirituality.

Religiousness and spirituality (RS) are two ubiquitous aspects of human experience typically considered impervious to scientific investigation. Nevertheless, associations between RS and frontoparietal neural activity have been recently reported. However, much less is known about whether such activity is causally involved in modulating RS or just epiphenomenal to them. Here we combined two-pulse (10 Hz) Transcranial Magnetic Stimulation (TMS) with a novel, ad-hoc developed RS-related, Implicit Association Test (IAT) to investigate whether implicit RS representations, although supposedly rather stable, can be rapidly modified by a virtual lesion of inferior parietal lobe (IPL) and dorsolateral prefrontal cortex (DLPFC). A self-esteem (SE) IAT, focused on self-concepts nonrelated to RS representations, was developed as control. A specific increase of RS followed inhibition of IPL demonstrating its causative role in inducing fast plastic changes of religiousness/spirituality. In contrast, DLPFC inhibition had more widespread effects probably reflecting a general role in the acquisition or maintenance of task-rules or in controlling the expression of self-related representations not specific to RS.

Susceptibility to the rubber hand illusion does not tell the whole body-awareness story.

The rubber hand illusion (RHI) is an enigmatic illusion that creates a feeling of owning an artificial limb. Enthusiasts of this paradigm assert that it operationalizes bodily self-awareness, but there are reasons to doubt such a clear link. Because little is known about other functional contributions to the RHI, including effects of context-dependent visual processing and cognitive control or the ability to resolve intermodal conflict, we carried out two complementary experiments. In the first, we examined the relationships between the RHI and (1) body awareness, as assessed by the Body Perception Questionnaire (BPQ); (2) context-dependent visual processing, as assessed by the rod-and-frame test (RFT); and (3) conflict resolution, as assessed by the Stroop test. We found a significant positive correlation between the RHI-associated proprioceptive drift and context-dependent visual processing on the RFT, but not between the RHI and body awareness on the BPQ. In the second experiment, we examined the RHI in advanced yoga practitioners with an embodied lifestyle and a heightened sense of their own body in space. They succumbed to the illusion just as much as did yoga-naïve control participants, despite significantly greater body awareness on the BPQ. These findings suggest that susceptibility to the RHI and awareness of one's own body are at least partially independent processes.

Impaired mental rotation in benign paroxysmal positional vertigo and acute vestibular neuritis.

Vestibular processing is fundamental to our sense of orientation in space which is a core aspect of the representation of the self. Vestibular information is processed in a large subcortical-cortical neural network. Tasks requiring mental rotations of human bodies in space are known to activate neural regions within this network suggesting that vestibular processing is involved in the control of mental rotation. We studied whether mental rotation is impaired in patients suffering from two different forms of unilateral vestibular disorders (vestibular neuritis - VN - and Benign Paroxysmal positional Vertigo - BPPV) with respect to healthy matched controls (C). We used two mental rotation tasks in which participants were required to: (i) mentally rotate their own body in space (egocentric rotation) thus using vestibular processing to a large extent and (ii) mentally rotate human figures (allocentric rotation) thus using own body representations to a smaller degree. Reaction times and accuracy of responses showed that VN and BPPV patients were impaired in both tasks with respect to C. Significantly, the pattern of results was similar in the three groups suggesting that patients were actually performing the mental rotation without using a different strategy from the control individuals. These results show that dysfunctional vestibular inflow impairs mental rotation of both own body and human figures suggesting that unilateral acute disorders of the peripheral vestibular input massively affect the cerebral processes underlying mental rotations.

Radiolabeled WBC scintigraphy in the diagnostic workup of patients with suspected device-related infections.

OBJECTIVES: The aim of this study was to investigate the diagnostic performance of (99m)Tc-hexamethypropylene amine oxime labeled autologous white blood cell ((99m)Tc-HMPAO-WBC) scintigraphy in patients with suspected infections associated with cardiovascular implantable electronic devices (CIEDs). BACKGROUND: Early, definite recognition of CIED-related infections combined with accurate localization and quantification of disease burden is a prerequisite for optimal treatment strategies. METHODS: All 63 consecutive patients underwent clinical examination, blood chemistry, microbiology, and echography of the cardiac region/venous pathway of the device. Final diagnosis of infection was established in 32 of 63 patients and in 23 of 32 by microbiology. RESULTS: Sensitivity of (99m)Tc-HMPAO-WBC single-photon emission computed tomography/computed tomography (SPECT/CT) was 94% for both detection and localization of CIED-associated infection. SPECT/CT imaging had a definite added diagnostic value over both planar and stand-alone SPECT. Pocket infection was often associated with lead(s) involvement; the intracardiac portion of the lead(s) more frequently exhibited (99m)Tc-HMPAO-WBC accumulation and presented the highest rate of complications, infectious endocarditis, and septic embolism. Two false negative cases and no false positive results were observed. None of the patients with negative (99m)Tc-HMPAO-WBC scintigraphy developed CIED-related infection during follow-up of 12 months. Echography of the cardiac region/venous pathway of the device had 90% specificity, but low sensitivity (81% when intracardiac lead[s] infection only was considered). The Duke criteria had 31% sensitivity for the definite category (100% specificity) and 81% for the definite and possible categories (77% specificity). CONCLUSIONS: (99m)Tc-HMPAO-WBC scintigraphy enabled the confirmation of the presence of CIED-associated infection, definition of the extent of device involvement, and detection of associated complications. Moreover, (99m)Tc-HMPAO-WBC scintigraphy reliably excluded device-associated infection during a febrile episode and sepsis, with 95% negative predictive value.

Hypnotic modulation of pain perception and of brain activity triggered by nociceptive laser stimuli.

INTRODUCTION: Neuroimaging studies indicate that hypnotic suggestions of increased and decreased pain intensity and unpleasantness may modulate somatosensory and cingulate cortex activity, respectively. METHODS: Using a within subject design and a strict subject selection procedure, we tested in High (Highs) and Low (Lows) hypnotically suggestible individuals whether hypnotic suggestions of sensory and affective hypoalgesia or hyperalgesia differentially affected subjective ratings of laser-induced pain and nociceptive-related brain activity in the time- and time-frequency domain. RESULTS: Hypnotic modulation of pain intensity and unpleasantness affected subjective ratings of laser-induced pain only in Highs. Such modulation was more specific for unpleasantness manipulation and more evident for suggestions of hyperalgesia. Importantly, Highs and Lows showed increase and decrease of P2a and P2b wave amplitudes and gamma band power, respectively. CONCLUSIONS: Hypnotic suggestions exerted a top-down modulatory effect on both evoked and induced-cortical brain responses triggered by selective nociceptive laser inputs. Furthermore, correlation analyses indicated that gamma power modulation and suggestions of hyperalgesia may reflect the process of allocating control resources to salient and threatening sensory-affective dimensions of pain.

Representing actions through their sound.

Since the discovery of 'mirror neurons' in the monkey premotor and parietal cortex, an increasing body of evidence in animals and humans alike has supported the notion of the inextricable link between action execution and action perception. Although research originally focused on the relationship between performed and viewed actions, more recent studies highlight the importance of representing the actions of others through audition. In the first part of this article, we discuss animal studies, which provide direct evidence that action is inherently linked to multi-sensory cues, as well as the studies carried out on healthy subjects by using state-of-the-art cognitive neuroscience techniques such as functional magnetic resonance imaging (fMRI), event-related potentials (ERP), magnetoencephalography (MEG), and transcranial magnetic stimulation (TMS). In the second section, we review the lesion analysis studies in brain-damaged patients demonstrating the link between 'resonant' fronto-parieto-temporal networks and the ability to represent an action by hearing its sound. Moreover, we examine the evidence in favour of somatotopy as a possible representational rule underlying the auditory mapping of actions and consider the links between language and audio-motor action mapping. We conclude with a discussion of some outstanding questions for future research on the link between actions and the sounds they produce.

Selective deficit of mental visual imagery with intact primary visual cortex and visual perception.

There is a vigorous debate as to whether visual perception and imagery share the same neuronal networks, whether the primary visual cortex is necessarily involved in visual imagery, and whether visual imagery functions are lateralized in the brain. Two patients with brain damage from closed head injury were submitted to tests of mental imagery in the visual, tactile, auditory, gustatory, olfactory and motor domains, as well as to an extensive testing of cognitive functions. A computerized mapping procedure was used to localize the site and to assess the extent of the lesions. One patient showed pure visual mental imagery deficits in the absence of imagery deficits in other sensory domains as well as in the motor domain, while the other patient showed both visual and tactile imagery deficits. Perceptual, language, and memory deficits were conspicuously absent. Computerized analysis of the lesions showed a massive involvement of the left temporal lobe in both patients and a bilateral parietal lesion in one patient. In both patients the calcarine cortex with the primary visual area was bilaterally intact. Our study indicates that: (i) visual imagery deficits can occur independently from deficits of visual perception; (ii) visual imagery deficits can occur when the primary visual cortex is intact and (iii) the left temporal lobe plays an important role in visual mental imagery.

Kinesthetic imagery and tool-specific modulation of corticospinal representations in expert tennis players.

Specific physical or mental practice may induce short- and long-term neuroplastic changes in the motor system and cause tools to become part of one's own body representation. Athletes who use tools as part of their practice may be an excellent model for assessing the neural correlates of possible bodily representation changes that are specific to extensive practice. We used single-pulse transcranial magnetic stimulation to measure corticospinal excitability in forearm and hand muscles of expert tennis players and novices while they mentally practiced a tennis forehand, table tennis forehand, and a golf drive. The muscles of expert tennis players showed increased corticospinal facilitation during motor imagery of tennis but not golf or table tennis. Novices, although athletes, were not modulated across sports. Subjective reports indicated that only in the tennis imagery condition did experts differ from novices in the ability to form proprioceptive images and to consider the tool as an extension of the hand. Neurophysiological and subjective data converge to suggest a key role of long-term experience in modulating sensorimotor body representations during mental simulation of sports.

Corticospinal facilitation during first and third person imagery.

Motor imagery can be defined as the covert rehearsal of movement. Previous research with transcranial magnetic stimulation (TMS) has demonstrated that motor imagery increases the corticospinal excitability of the primary motor cortex in the area corresponding to the representation of the muscle involved in the imagined movement. This research, however, has been limited to imagery of oneself in motion. We extend the TMS research by contrasting first person imagery and third person imagery of index finger abduction-adduction movements. Motor evoked potentials were recorded from first dorsal interosseous (FDI) and abductor digiti minimi (ADM) during single pulse TMS. Participants performed first and third person motor imagery, visual imagery, and static imagery. Visual imagery involved non biological motion while static imagery involved a first person perspective of the unmoving hand. Relative to static imagery, excitability during imagined movement increased in FDI but not ADM. The facilitation in first person imagery adds to previous findings. A greater facilitation of MEPs recorded from FDI was found in third person imagery where the action was clearly attributable to another person. We interpret this novel result in the context of observed action and imagined observation of self action, and attribute the result to activation of mirror systems for matching the imagined action with an inner visuo-motor template.

Selective impairment of hand mental rotation in patients with focal hand dystonia.

Mental rotation of body parts determines activation of cortical and subcortical systems involved in motor planning and execution, such as motor and premotor areas and basal ganglia. These structures are severely impaired in several movement disorders, including dystonia. Writer's cramp is the most common form of focal hand dystonia. This study investigates whether patients affected by writer's cramp present with difficulties in tasks involving mental rotation of body parts and whether any impairments are specific to the affected hand or generalized to other body parts. For this purpose we tested 15 patients with right writer's cramp (aged 21-68 years, 8 women) and 15 healthy control subjects (10 women, age and education matched). Stimuli consisted of realistic photographs of hands and feet presented on a computer monitor in different orientations with respect to the upright canonical orientation. In each trial, subjects gave a laterality judgement by reporting verbally whether the presented body part was left or right. Two main results of the study are, firstly, writer's cramp patients are slower than controls in mentally rotating hands [F (1,28) = 5.4; P = 0.028] but not feet, and secondly, the pattern of response times to stimuli at various orientations suggests that the mental motor imagery of controls and patients reflects the type of processes and mechanisms called into play during actual execution of the same movements. In particular, increased difficulty in rotating right-sided stimuli at 120 degrees and left-sided stimuli at 240 degrees would suggest that mental rotation of body parts reflects the anatomical constraints of real hand movements. In conclusion, patients with writer's cramp presented mental rotation deficits specific to the hand. Importantly, deficits were present during mental rotation of both the right (affected) and the left (unaffected) hand, thus suggesting that the observed alterations may be independent and even exist prior to overt manifestations of dystonia.

Mediastinal images resembling thymus following 131-I treatment for thyroid cancer.

The follow-up of Differentiated Thyroid Cancer conventionally includes serum thyroglobulin and periodic Whole Body Scans. The uptake of 131-I in normal and pathological tissues different from metastatic thyroid cancer sites is a cause of false-positive scans. Among them, mediastinal uptake caused by thymic hyperplasia can be observed. The aim of the present study was to review a series of 573 patients with differentiated thyroid cancer treated with 131-I after surgery between 1992 and 2003 looking above all for those with mediastinal images resembling thymus. This evaluation is presented together with some hypotheses on the relationships between thymus and thyroid. Moreover, some considerations are made on the differential diagnosis between thymus and mediastinal tumour thyroid residues.

Sublingual buprenorphine and methadone maintenance treatment: a three-year follow-up of quality of life assessment.

This study was conducted to compare long-term outcome effects on the quality of life (QOL) of oral methadone with sublingual buprenorphine maintenance treatment. The QOL status of opioid-dependent patients was assessed using the German version ("Berlin Quality of Life Profile") of the Lancashire Quality of Life Profile. Physical symptoms were measured using the Opiate Withdrawal Scale (OWS). Urine tests were carried out randomly to detect additional consumption. In the first study period, 53 opioid-dependent subjects were enrolled and 25 could be reached after 3 years. The retention rate was 50% for methadone and 45% for buprenorphine (p = 0.786). Baseline values of the total sample (completers and noncompleters) QOL and somatic complaints did not show significant differences between the two treatment groups. QOL characteristics at 6 months of treatment of the buprenorphine completer and noncompleter groups differed significantly regarding job (p = 0.013), family, and total score of physical symptoms (p = 0.002), in which the completer group showed the more favorable values. Concerning physical symptoms at 36 months, logistic regression revealed significantly less stomach cramps (p = 0.037) and fatigue and tiredness (p = 0.034) in buprenorphine compared to the methadone. Moreover, the buprenorphine-maintained group showed significantly less additional consumption of benzodiazepines (p = 0.015) compared with methadone participants. It is concluded that opioid addicts improved their QOL and health status when treated with methadone or buprenorphine. In summary, regarding QOL and health status, the present data indicate that buprenorphine is also a useful long-term alternative for maintenance treatment of opioid-dependent patients.

[Current consumer conditions among opioid addicts--implications for maintenance-treatment programmes provided by ambulatory drug treatment centers and physicians]. / Aktuelle Konsumformen bei Drogenabhängigkeit--Implikationen für Substitutionsprogramme in ambulanten Einrichtungen und bei behandelnden Arzten.

BACKGROUND: Anonymous evaluation of the current conditions of drug scene and drug consumption, entrance age, personal motives for drug consumption and satisfaction among opioid-dependent clients with treatments available within an ambulant maintenance treatment setting. METHODS: The questionnaire for the study was based on representative studies and covered 112 questions regarding drug consumption. In addition, an instrument of the "Hessische Landesstelle gegen die Suchtgefahren", which measures satisfaction of opioid clients regarding public drug-treatment centers, was used. RESULTS: A total of 158 opioid clients within an ambulant maintenance treatment setting were enrolled in the study. The mean age at first drug consumption was 15.1 (2.4) years for men and 15.2 (3.5) years for women. The Spearman correlation showed a significant positive correlation (r=0.284) between age and time of first drug consumption (p=0.019). Cannabis was the most frequent entrance drug (55.8%), followed by alcohol (33.8%), opioids (17.6%) and nicotine (11.8%). Additional consumption of benzodiazepines was observed in 44.7% of men and 39.7% of women, of cannabis in 74.5% of men and 52.4% of women, and of sustained-release morphine in 41.4% of men and 33.3% of women. Within the previous 6-12 months cocaine was consumed significantly less (p=0.024) by men (63.8%) than by women (90.5%). 93.3% of the drug users rated a follow-up assistance programme after withdrawal and 71.9% special care programmes for designer drugs very important. IMPLICATIONS: The present study supports the assumption of an earlier age of first drug consumption. In view of our findings on entrance age, and on polytoxicomanic consumption patterns and gender-specific differences, we believe that the objectives of substitution programmes can only be reached if programmes are adequately adapted to the actual conditions of the drug scene and are able to cooperate with other public drug-treatment systems.

Therapeutic effects of peripheral repetitive magnetic stimulation on myofascial pain syndrome.

OBJECTIVE: To evaluate short- and medium-term effects of peripheral repetitive magnetic stimulation (rMS) on myofascial pain. METHODS: Eighteen patients who presented with myofascial trigger points (TPs) at the level of the superior trapezius were separated into two groups according to a restricted randomization scheme. Group 1 (n=9) underwent treatment with rMS that consisted of a total of 10 sessions, each lasting 20min, in which 4000 magnetic stimuli were administered in 5s trains at 20Hz at the TP. Group 2 (n=9) received a placebo treatment that consisted of the application of a non-functioning ultrasound therapy device to the TP. Patients were evaluated before treatment, at the end of treatment, and again 1 week and 1 month after the conclusion of the treatment. Clinical evaluation included parameters for measuring pain levels (VAS, NPDVAS and algometry), the myofascial TP characteristics and the range of cervical movement (ROM). RESULTS: The rMS group showed a significant improvement in VAS, NPDVAS, algometry, as well as in the characteristics of the TP after conclusion of treatment. Improvements in the ROM were also present in rotation and controlateral bending. This improvement persisted after 1 month. On the other hand, the placebo group did not show any significant improvement in the tests considered. CONCLUSIONS: The results of this study show that peripheral rMS may have positive short- and medium-term therapeutic effects on myofascial pain.

The effect of two different rehabilitation treatments in cervical dystonia: preliminary results in four patients.

The most widespread approach to rehabilitation of cervical dystonia is electromyographic (EMG) biofeedback. However, consensus is lacking regarding the true effectiveness of this technique. The aim of this study was to evaluate how cervical dystonia was influenced by two rehabilitative treatments, namely a standard biofeedback program and a novel physiotherapy program consisting of postural reeducation exercises and passive elongation of myofascial cervical structures. Both programs were consecutively administered to 4 patients with cervical dystonia. The study design was a behavioral analysis of single cases. The main outcome measures were a head realignment test, a disability questionnaire and a pain visual analogue scale (VAS). Each patient's performance was evaluated before the study and after the first and second program. Furthermore, the disability questionnaire and the pain VAS were administered 3, 6, and 9 months after the end of the treatments. The physiotherapy program showed therapeutic effects comparable to those of EMG biofeedback. Reductions of disability and of pain were still present 3-9 months after the end of the treatments. These preliminary results suggest that the physiotherapy program proposed in the present study may be a promising method for rehabilitation of cervical dystonia.

Deficits of temporal discrimination in dystonia are independent from the spatial distance between the loci of tactile stimulation.

To assess whether spatial variables influence deficits of temporal somesthetic discrimination in dystonic patients, 10 patients with idiopathic dystonia and 12 healthy controls were tested with pairs of non-noxious electrical stimuli separated by different time intervals. Stimuli were delivered: (1) to the pad of the index finger (same-point condition), (2) to the pad and to the base of the index finger (same-finger condition), and (3) to the pad of the index and ring fingers (different-finger condition). Subjects were asked to report whether they perceived single or double stimuli in the first condition and synchronous or asynchronous stimuli in the second and third conditions. Somesthetic temporal discrimination thresholds (STDTs) were obtained by computing the shortest time interval at which stimuli, applied to the left or the right hand, were perceived as separate in the first condition or asynchronous in the second and third conditions. STDTs were significantly higher in dystonic patients than controls in all three conditions. In both dystonia patients and controls, STDTs resulted highest in conditions whereby stimuli were maximally separated in space. Results extend current knowledge of deficits of somesthetic temporal discrimination in dystonia by showing that temporal deficits are not influenced by spatial variables.