Involvement of superior temporal areas in audiovisual and audiomotor speech integration.

Perception of speech sounds is affected by observing facial motion. Incongruence between speech sounds and watching somebody articulating may influence the perception of auditory syllable, referred to as the McGurk effect. We tested the degree to which silent articulation of a syllable also affects speech perception and searched for its neural correlates. Listeners were instructed to identify the auditory syllables /pa/ and /ta/ while silently articulating congruent/incongruent syllables or observing videos of a speaker's face articulating them. As a baseline, we included an auditory-only condition without competing visual or sensorimotor input. As expected, perception of sounds degraded when incongruent syllables were observed, and also when they were silently articulated, albeit to a lesser extent. This degrading was accompanied by significant amplitude modulations in the beta frequency band in right superior temporal areas. In these areas, the event-related beta activity during congruent conditions was phase-locked to responses evoked during the auditory-only condition. We conclude that proper temporal alignment of different input streams in right superior temporal areas is mandatory for both audiovisual and audiomotor speech integration.

When distance matters: Perceptual bias and behavioral response for approaching sounds in peripersonal and extrapersonal space.

Studies on sound perception show a tendency to overestimate the distance of an approaching sound source, leading to a faster reaction time compared to a receding sound source. Nevertheless, it is unclear whether motor preparation and execution change according to the perceived sound direction and distance, particularly when the sound falls inside the individual's peripersonal space. In this study we developed several auditory stimuli by means of two speakers, generating sounds moving toward the perceiver but stopping at different distances from her/him. Participants were asked to raise their arms as soon as the sound stopped, and their premotor and motor movement components were recorded by means of electromyography (EMG). Error in locating the perceived sound distance was also measured by asking participants to walk to the point in space where they believed the sound had stopped. Results showed that action initiation was anticipated as a function of sound distance: the closer the sound, the earlier the movement onset, when the sound entered the subject's peripersonal space. Less error for distance estimation was present when the sound was inside the peripersonal space with a modulation in the order of a few centimeters. Overall, our results reveal a link between perceptual bias in sound distance evaluation and peripersonal space, suggesting the presence of motor plan specificity.

Fitts' Law in early postural adjustments.

We tested a hypothesis that the classical relation between movement time and index of difficulty (ID) in quick pointing action (Fitts' Law) reflects processes at the level of motor planning. Healthy subjects stood on a force platform and performed quick and accurate hand movements into targets of different size located at two distances. The movements were associated with early postural adjustments that are assumed to reflect motor planning processes. The short distance did not require trunk rotation, while the long distance did. As a result, movements over the long distance were associated with substantial Coriolis forces. Movement kinematics and contact forces and moments recorded by the platform were studied. Movement time scaled with ID for both movements. However, the data could not be fitted with a single regression: Movements over the long distance had a larger intercept corresponding to movement times about 140 ms longer than movements over the shorter distance. The magnitude of postural adjustments prior to movement initiation scaled with ID for both short and long distances. Our results provide strong support for the hypothesis that Fitts' Law emerges at the level of motor planning, not at the level of corrections of ongoing movements. They show that, during natural movements, changes in movement distance may lead to changes in the relation between movement time and ID, for example when the contribution of different body segments to the movement varies and when the action of Coriolis force may require an additional correction of the movement trajectory.

Action anticipation beyond the action observation network: a functional magnetic resonance imaging study in expert basketball players.

The ability to predict the actions of others is quintessential for effective social interactions, particularly in competitive contexts (e.g. in sport) when knowledge about upcoming movements allows anticipating rather than reacting to opponents. Studies suggest that we predict what others are doing by using our own motor system as an internal forward model and that the fronto-parietal action observation network (AON) is fundamental for this ability. However, multiple-duty cells dealing with action perception and execution have been found in a variety of cortical regions. Here we used functional magnetic resonance imaging to explore, in expert basketball athletes and novices, whether the ability to make early predictions about the fate of sport-specific actions (i.e. free throws) is underpinned by neural regions beyond the classical AON. We found that, although involved in action prediction, the fronto-parietal AON was similarly activated in novices and experts. Importantly, athletes exhibited relatively greater activity in the extrastriate body area during the prediction task, probably due to their expert reading of the observed action kinematics. Moreover, experts exhibited higher activation in the bilateral inferior frontal gyrus and in the right anterior insular cortex when producing errors, suggesting that they might become aware of their own errors. Correct action prediction induced higher posterior insular cortex activity in experts and higher orbito-frontal activity in novices, suggesting that body awareness is important for performance monitoring in experts, whereas novices rely more on higher-order decision-making strategies. This functional reorganization highlights the tight relationship between action anticipation, error awareness and motor expertise leading to body-related processing and differences in decision-making processes.

Motor system modulation for movement direction and rotation angle during motor imagery.

Transcranial magnetic stimulation (TMS) studies have shown that the motor system is facilitated when we imagine performing motor actions. However, it is not clear whether the individual's motor system modulates bilaterally and selectively for task parameters, such as movement direction and amplitude. To investigate this issue, we applied single-pulse TMS over the left and right primary motor cortex (M1) of healthy subjects, who had to imagine grasping and rotating a clock hour hand, having a starting position at noon, towards four different times: 2, 5, 7 and 10 o'clock. Rotations could be in clockwise (2 and 5 o'clock) or counter-clockwise (7 and 10 o'clock) directions and could require small (2 and 10 o'clock) or large (5 and 7 o'clock) rotation angle. TMS motor-evoked potentials were recorded for three muscles, and movements were imagined with the right and left hands. Results showed that during motor imagery a mirroring pattern was present between the right and the left motor cortices, showing selective activation of the hand-intrinsic muscles spatially close to the direction of the imagined movement. Overall a higher activation for large and a lower activation for small rotation angle were found, but no selective muscle activity was present within the hand-intrinsic muscles for this parameter. Following these results we propose that during action imagination an internally coded covariance between movement parameters is present with a muscle-specific activation for movement direction.

Does movement planning follow Fitts' law? Scaling anticipatory postural adjustments with movement speed and accuracy.

We wanted to determine whether movement planning followed Fitts' law by investigating the relationship between movement planning and movement performance in experienced dancers executing a typical classical ballet step in which the big toe was pointed to targets at different distances and of different widths so as to obtain several indices of difficulty (ID). Movement time, velocity and variability at the target were the variables of movement performance kinematics; movement planning was evaluated by analysis of anticipatory postural adjustments (APAs) to assess their modulation at different IDs. Movement time and peak of velocity were found to scale with the ID only when individual movement distance across target widths was entered into the analysis. APA magnitude and duration both scaled according to movement parameters but not in the same way. APA magnitude scaled with movement velocity, while APA duration was sensitive to the amplitude-to-accuracy ratio following the ID for movements performed in the shortest time interval when on-line feedback control is probably not available. Here we show that timing of muscle activation acts as an independent central command that triggers fine-tuning for speed-accuracy trade-off.

Motor imagery beyond the joint limits: a transcranial magnetic stimulation study.

The processes and neural bases used for motor imagery are also used for the actual execution of correspondent movements. Humans, however, can imagine movements they cannot perform. Here we explored whether plausibility of movements is mapped on the corticospinal motor system and whether the process is influenced by visuomotor vs. kinesthetic-motor first person imagery strategy. Healthy subjects imagined performing possible or biomechanically impossible right index finger movements during single pulse TMS of the left motor cortex. We found an increase of corticospinal excitability during motor imagery which was higher for impossible than possible movements and specific for the muscle involved in the actual execution of the imagined movement. We expand our previous action observation studies, suggesting that the plausibility of a movement is computed in regions upstream the primary motor cortex, and that motor imagery is a higher-order process not fully constrained by the rules that govern motor execution.

Expertise with pathological actions modulates a viewer's motor system.

Brain mechanisms for action understanding rely on matching the observed actions into the viewer's motor system. Health professionals, who treat patients affected by movement disorders as dystonia, frequently see hyperkinetic action patterns characterized by an overflow of muscle co-contractions. To avert an overload of the motor system during observation of those actions, they might need to look at dystonic motor symptoms in a cool, detached way. To investigate whether visual expertise about atypical movement kinematics influences the viewer's motor system, we applied transcranial magnetic stimulation to clinicians and to naive subjects, while they observed handwriting actions performed with two different kinematics: fluent and non-fluent. Crucially, the latter movement pattern was easily recognized by the clinicians as a typical expression of writer's cramp, whereas it was unknown to the naive subjects. Results showed that clinicians had similar corticospinal activation during observation of dystonic and healthy writings, whereas naive subjects were hyper-activated during observation of dystonic movements. Hyper-activation was selective for the muscles directly involved in the dystonic co-contractions and inversely correlated with subjective movement fluency scores, hinting at a fine-tuned association between the breakdown of observed movement fluency and corticospinal activation. These findings suggest that observation of unusual pathological actions differently modulates the viewer's motor system, depending on knowledge, visual expertise, and ability in recognizing suboptimal movement kinematics.

Oral beclometasone dipropionate in the treatment of extensive and left-sided active ulcerative colitis: a multicentre randomised study.

AIM: To explore the efficacy and safety of the topically acting steroid beclometasone dipropionate (BDP) in an oral controlled release formulation in the treatment of extensive or left-sided ulcerative colitis. METHODS: In a multicentre, randomised, parallel-group, single-blind study, patients with active mild to moderate ulcerative colitis were randomised to a 4-week treatment with BDP 5 mg/day o.d. vs. 5-ASA 0.8 g t.d.s. The primary efficacy variable was the decrease of Disease Activity Index (DAI) (clinical symptoms and endoscopic appearance of mucosa). Safety was evaluated by monitoring adverse events, vital signs, haematochemical parameters and adrenal function. RESULTS: One hundred and seventy-seven patients were enrolled and randomly treated with BDP (n = 90) or 5-ASA (n = 87). Mean DAI score decreased in both treatments groups (P < 0.0001 vs. baseline for both groups). Clinical remission was achieved in 63.0% of patients in the BDP group vs. 62.5% in the 5-ASA group. A significant DAI score improvement (P < 0.05) in favour of BDP was observed in patients with extensive disease. Both treatments were well tolerated. Mean plasma cortisol levels were significantly reduced vs. baseline in BDP recipients, but without signs of pituitary-adrenal function depletion. CONCLUSION: Oral BDP gave an overall treatment result in patients with active ulcerative colitis without signs of systemic side-effects.

A common perceptual parameter for stair climbing for children, young and old adults.

In this paper we examine whether a common perceptual parameter is available for guiding old adults, young adults and children in climbing the highest stair mountable in a bipedal fashion. Previous works have shown that the ratio between the height of the stair and the hip height was the body-scaled invariance adopted as information for selecting the highest stair by young adults [Journal of Experimental Psychology: Human Perception and Performance 10 (1984) 683-703] but not by older adults [Journal of Experimental Psychology: Human Perception and Performance 3 (1992) 691-697]. Indeed, for older adults additional bio-mechanical parameters needed to be added to the model due to their decrease in leg strength and flexibility.Up to now, no perceptual invariant has been identified yet for determining the relevant information used for guiding the stair climbing action for normal healthy people. We propose a new parameter as the angle defined by the ratio between the height of the stair and the distance taken from the feet to the top edge of the stair before the initiation of the movement. We show that this angle is the same for children, young adults and older adults despite the different kinematics of the motion, the anthropometrics and the skill ability exhibit by the participants. In summary we show that even when the climbability judgments, based on the simple ratio leg length-stair height, are influenced by differences in age, participants use a common perceptual variable when they are coordinating their stair climbing action.

Mortality in patients with coeliac disease and their relatives: a cohort study.

BACKGROUND: Although previous studies have shown increased mortality in patients with coeliac disease and their relatives, no data are available in relation to different patterns of clinical presentation. We assessed mortality in patients with coeliac disease and their first-degree relatives. METHODS: We enrolled, in a prospective cohort study, 1072 adult patients with coeliac disease consecutively diagnosed in 11 gastroenterology units between 1962 and 1994, and their 3384 first-degree relatives. We compared the number of deaths up to 1998 with expected deaths and expressed the comparison as standardised mortality ratio (SMR) and relative survival ratio. FINDINGS: 53 coeliac patients died compared with 25.9 expected deaths (SMR 2.0 [95% CI 1.5-2.7]). A significant excess of mortality was evident during the first 3 years after diagnosis of coeliac disease and in patients who presented with malabsorption symptoms (2.5 [1.8-3.4]), but not in those diagnosed because of minor symptoms (1.1 [0.5-2.2]) or because of antibody screening (1.2 [0.1-7.0]). SMR increased with increasing delay in diagnosis and for patients with poor compliance with gluten-free diet. Non-Hodgkin lymphoma was the main cause of death. No excess of deaths was recorded in relatives with coeliac disease. INTERPRETATION: Prompt and strict dietary treatment decreases mortality in coeliac patients. Prospective studies are needed to clarify the progression of mild or symptomless coeliac disease and its relation to intestinal lymphoma.

Effects of different carbohydrate sources on the growth of Tuber borchii Vittad. mycelium strains in pure culture.

The influence of carbohydrate utilisation on the growth of three strains of Tuber borchii Vittad. mycelium (1BO, 17BO and 10RA) in culture was assessed using culture media containing glucose (control), mannose or mannitol. Mannose was the best substrate for growth of the strains and this was particularly evident for strain 17BO. Mannitol instead was metabolized only by 10RA and 1BO. In order to explain the different growth trends, analyses of enzyme levels, kinetic parameters, protein patterns and the morphology of the three strains were carried out. Our results show that these strains of T. borchii mycelium were affected by the substrates used in the media. The aim of the present work was to optimise the in vitro production of T. borchii mycelium for use in experiments which require the fungus in precise and reproducible conditions, such as mycorrhizal synthesis or protein and nucleic acid extractions.

Analysis of kinematically redundant reaching movements using the equilibrium-point hypothesis.

Six subjects performed a planar reaching arm movement to a target while unpredictable perturbations were applied to the endpoint; the perturbations consisted of pulling springs having different stiffness. Two conditions were applied; in the first, subjects had to reach for the target despite the perturbation, in the second condition, the subjects were asked to not correct the motion as a perturbation was applied. We analyzed the kinematics profiles of the three arm segments and, by means of inverse dynamics, calculated the joint torques. The framework of the equilibrium-point (EP) hypothesis, the lambda model, allowed the reconstruction of the control variables, the "equilibrium trajectories", in the "do not correct" condition for the wrist and the elbow joints as well as for the end point final position, while for the other condition, the reconstruction was less reliable. The findings support and extend to a multiple-joint planar movement, the paradigm of the EP hypothesis along with the "do not correct" instruction.

Peptic ulcer bleeding: comparison of two hemostatic procedures.

OBJECTIVE: Bleeding is a serious complication of peptic ulcer. Endoscopic injection therapy is accepted as a homeostatic endoscopic treatment in acute nonvariceal of upper GI hemorrhages, particularly in bleeding peptic ulcers. The risk of rebleeding is predicted by the endoscopic appearance of ulcer features classified according to Forrest's criteria. METHODS: Two hundred twenty-three patients were selected from 1,003 emergency upper endoscopies for GI bleeding. According to Forrest's criteria, 99 well-matched patients with ulcers F1 and F2 were considered at risk of rebleeding; 54 patients (group A) received local ulcer injection of epinephrine solution 1:10,000, whereas (group B) patients were treated with local epinephrine injection and then with endoscopic Hemoclips. (1) We considered the control of bleeding, the number of rebleeding episodes, the need for emergency surgery, and mortality. RESULTS: Bleeding ulcers stopped completely in 83.3% group A patients, and in 95.6% group B patients (p = not significant). In a subset of F1b patients the rebleeding rate was 31 % for group A and 0% for group B (p < 0.05). There was no mortality as a result of the procedure. There was a trend toward reducing surgery in favor of the combined therapy (0% vs 7.4%). No differences were found in transfusion requirements or mean hospitalization days. CONCLUSIONS: We conclude that endoscopic injection of l:10,000 epinephrine solution alone and epinephrine solution plus application of Hemoclips are equivalent therapies in treating bleeding and rebleeding from peptic ulcers. There was no difference between therapies in terms of need for surgery or mortality. Possibly combination therapy is more effective in treating ulcers that are actively oozing.

Body-scaled transitions in human grip configurations.

This article reports two experiments that were set up to examine the preferred human grip configuration used to displace cubes that varied in length (Lc), mass (Mc), and density (ML3). In particular, the authors sought to provide a more precise test of a dimensional relation between the object and the hand that had previously been shown to predict the grip configuration used to transport an object from one location to another. The experiments examined 2 grip transitions (from 3 digits to 4 digits and from 1 hand to 2 hands) within 2 sets of object conditions. In Experiment 1, cubes with a low density and a small increment in size (1 mm) were used, whereas in Experiment 2, cubes with 2 fixed sizes and small increments in mass were used. The results showed that the body-scaled equation K = logLc + (logMc/a + bMh + cLh), where Mh and Lh are the anthropometric measures of the hand mass and length and a, b, and c are empirical constants, is the body-scaled information that predicts the grip configurations used to displace objects.

Body scaling of grip configurations in children aged 6-12 years.

This study examined the influence of body scale on the grip configurations used by young children (6-12 years old) to displace cubes that varied systematically in size (L) and mass (M). It was determined if the scaling relation we had developed for adults K = log Lc + ((log Mc)/(a + bLh + cMh)) where L(c) and M(c) is the length side and mass of the cubes, respectively, and L(h) and M(h) are the length and mass of the hand, respectively, it would also predict the change in grip configurations across this age range in a fashion consistent with the principle of similitude. The statistical and scaling analyses revealed that the invariant body-scaled relation that specified the adult grip transitions also held for the 6- to 12-year-old children.

Relapse of low-grade gastric MALT lymphoma after Helicobacter pylori eradication: true relapse or persistence? Long-term post-treatment follow-up of a multicenter trial in the north-east of Italy and evaluation of the diagnostic protocol's adequacy.

The effect of eradication of Helicobacter pylori on early stage gastric low-grade MALT lymphoma in 76 patients with follow-up of at least 1 year (12-63 months, mean 28) is reported. No regression was found in five cases after 12-48 months. In one case surgical resection detected the involvement of perigastric lymph nodes overlooked by endoscopic ultrasonography (EUS). Neither progression of the disease nor a high-grade component was documented by repeated gastric mappings, EUS and complete stagings in the other four cases. After histological remission five relapses of low-grade and one relapse of high-grade MALT lymphoma were found 12-48 months after eradication. Subsequent histological remission, without any additional therapy, was found in three relapsed cases. A rapid and persistent histological remission was obtained in 56 patients (73%). A late remission was observed in six cases. Monoclonal remission was found in half of the patients and was frequently delayed. Persistent monoclonality was associated with histological remission in the vast majority of patients. Our data confirm H. pylori eradication as the first choice therapy for early stage gastric low-grade MALT lymphoma and recommend extensive bioptic mapping and endoscopic sonography both in the local staging and in the regression evaluation. The rare cases of late remission encourage us to wait for at least 1 year after eradication of H. pylori. Longer follow-up studies will clarify the meaning of histological relapse/persistence and late remission. The study of non-responder cases could show us a step in lymphomagenesis.

The natural history of ulcerative proctitis: a multicenter, retrospective study. Gruppo di Studio per le Malattie Infiammatorie Intestinali (GSMII).

OBJECTIVE: The aim of this study was to evaluate the clinical features and the long term evolution of patients with a well defined initial diagnosis of ulcerative proctitis. METHODS: Patients with an original diagnosis of ulcerative proctitis who had been seen at any of 13 institutions from 1989 to 1994 were identified. Data on disease onset and subsequent evolution were recorded. In addition, 575 patients with more extensive disease, treated in the same centers, were used as controls. RESULTS: A total of 341 patients satisfied the inclusion criteria. The percentage of smokers in these patients was slightly lower than in controls; no differences were found in the other clinical/demographic variables evaluated. A total of 273 patients entered long term follow-up (mean, 52 months). Proximal extension of the disease occurred in 74 of them (27.1%). The cumulative rate of proximal extension and of extension beyond the splenic flexure was 20% and 4% at 5 yr and 54% and 10% at 10 yr, respectively. The risk of proximal extension was higher in nonsmokers, in patients with >3 relapses/yr, and in patients needing systemic steroid or immunosuppressive treatment. Refractory disease was confirmed as an independent prognostic factor at multivariate analysis. CONCLUSIONS: Proximal extension of ulcerative proctitis is frequent and may occur even late after the original diagnosis. However, the risk of extension beyond the splenic flexure appears to be quite low. Smoking seems to be a protective factor against proximal extension, whereas refractoriness is a risk factor for proximal extension of the disease.

The scaling of human grip configurations.

The many degrees of freedom of the hand and arm afford the wide range and rich adaptability of human grip configurations in action. Several classification schemes of human grip configurations have been proposed, but none is based on scaling laws of physical biology, which are well established for other categorizations of fundamental physical activities such as locomotion. This study examined the preferred human grip configurations used to displace to a new location cubes that varied systematically in length (L), mass (M), and density (ML-3). The body-scaled equation K = log L + (log M)/h (where h refers to anthropometric measures of the hand) predicted the grip configurations used to displace objects. The findings suggest that information about the dynamic scaling relation is picked up visually and organizes the many degrees of freedom of the hand-arm complex in the coordination of prehensile grip configurations.

On taking the grasping out of prehension.

Smeets and Brenner provide a very clear and useful statement of the work that has been stimulated by Jeannerod's 1984 paper but seem more concerned about the viability of model fitting than model assumptions. The theoretical and practical limitations of viewing "grasping as nothing more than pointing" are noted. We reemphasize the importance in prehension of the union of the hand with the object in the act of realizing a task goal.