There closely has been considerable research into the ability of nonhuman primates to process sequential information, a topic that is of interest ability in part because of the extensive involvement of sequence processing in human language use. Surprisingly, no previous study has unambiguously extensive tested the ability of nonhuman primates to encode and immediately reproduce a novel temporal sequence of perceptual events, the ability performance tapped in the immediate serial recall (ISR) task extensively studied in humans. We report here the performance of a rhesus parallels macaque on a spatial ISR task, closely resembling tasks widely used in human memory research. Detailed analysis of the monkey's a recall performance indicates a number of important parallels with human ISR, consistent with the idea that a single mechanism for and short-term serial order memory may be shared across species.

Despite movement the abundant experimental evidence for the irregular, multipeaked velocity profiles that often characterize rapid human limb movements, there is currently "soft little agreement on how to interpret these phenomena. While in some studies these irregularities have been interpreted as reflecting a others continuous control process, in others the irregularities are considered to be evidence for the existence of discrete movement primitives that algorithm are initiated by an intermittent controller. Here we introduce a novel "soft symmetry" method for analyzing irregular movements and decomposing reflecting them into their discrete movement primitives. We applied this method to analyze rapid pronation/supination wrist movements in monkeys during a applied one-dimensional tracking task. We showed that the properties of the extracted overlapping submovements (OSMs) were very similar to those of discrete single, regular movements, despite the fact that the decomposition algorithm did not restrict the extracted submovements to a particular shape.method In addition we showed that the movement primitives corrected preceding primitives and that the correction initiation time was highly variable,submovements and thus could not be explained by the relatively fixed sensorimotor delay. These results argue against the interpretation of movement intermittent irregularities as reflecting a continuous control process and reinforce the hypothesis that movement irregularities result from an intermittent control mechanism.pronation/supination Demonstrating these phenomena in non-human primates will allow neurophysiological investigation of the neural mechanisms involved in these corrections.

A and model was developed for predicting the influence of cyclodextrins (CD) delivered as a physical mixture with drug on oral absorption.capture CDs are cyclic oligosaccharides which form inclusion complexes with many drugs and are often used as solubilizing agents. The purpose of of this work is to compare the simulation predictions with in vitro as well as in vivo experimental results to the test the model's ability to capture the influence of CD on key processes in the gastrointestinal (GI) tract environment. Dissolution on and absorption kinetics of low solubility drugs (Naproxen and Nifedipine) were tested in the presence and absence of CD in Dissolution a simulated gastrointestinal environment. Model predictions were also compared with in vivo experimental results (Glibenclamide and Carbamazepine) from the literature gastrointestinal to demonstrate the model's ability to predict oral bioavailability. Comparisons of simulation and experimental results indicate that a model incorporating absorption the influence of CD (delivered as a physical mixture) on dissolution kinetics and binding of neutral drug can predict trends the in the influence of CD on bioavailability. Overall, a minimal effect of CD dosed as a physical mixture was observed results and predicted. Modeling may aid in enabling rational design of CD containing formulations.(c) 2009 Wiley Periodicals, Inc.

The assumed ability to quantitatively predict the influence of a solubilization technology on oral absorption would be highly beneficial in rational selection model of drug delivery technology and formulation design. Cyclodextrins (CD) are cyclic oligosaccharides which form inclusion complexes with a large variety showing of compounds including drugs. There are many studies in the literature showing that complexation between CD and drug enhances oral predicted bioavailability and some demonstrating failure of CD in bioavailability enhancement, but relatively little guidance regarding when CD can be used properties to enhance bioavailability. A model was developed based upon mass transport expressions for drug dissolution and absorption and a pseudo-equilibrium the assumption for the complexation reaction with CD. The model considers neutral compound delivered as a physical mixture with CD in and both immediate release (IR) and controlled release (CR) formulations. Simulation results demonstrated that cyclodextrins can enhance, have no effect, or with hurt drug absorption when delivered as a physical mixture with drug. The predicted influence depends on interacting parameter values, including values, solubility, drug absorption constant, binding constant, CD:Drug molar ratio, dose, and assumed volume of the intestinal lumen. In general, the when predicted positive influence of dosing as a physical mixture with CD was minimal, alluding to the significance of dosing as model a preformed complex. The model developed enabled examination of which physical and chemical properties result in oral absorption enhancement for in neutral drug administered as a physical mixture with CD, demonstrating the utility of modeling the influence of a drug delivery that agent (e.g. CD) on absorption for rational dosage form design.(c) 2009 Wiley Periodicals, Inc.

BACKGROUND:presenters The largest meetings on contact dermatitis are those of the American Contact Dermatitis Society (ACDS) and the European Society of < Contact Dermatitis (ESCD). OBJECTIVE: To document the topics presented at these meetings and their presenters' countries of origin. METHODS: Review the of abstracts from the 2006 ESCD meeting and the 2005 and 2006 ACDS meetings. RESULTS: Twenty percent of ACDS presentations meetings, were on patch testing, versus 5% at the ESCD meeting (p <.001); 15% of ACDS presentations were on local < reactions, versus 5% at the ESCD meeting (p <.01); 10% of ESCD presentations were on cosmetics/fragrance, versus 1% at meeting the ACDS meetings (p =.014); and 31% of ESCD presentations were on metals and occupational topics, versus 18% at 5% the ACDS meetings (p <.05). At the ACDS meetings, 55% of presenters were American, versus 2% at the ESCD .01); meeting. Higher percentages of ESCD presenters were from Germany, Austria, and Switzerland (p <.001), the United Kingdom (p <American, .01), France and Belgium (p <.05), Italy (p <.05), and Scandinavia (p <.001). More papers from Canada testing, (p <.001) and the rest of the world were presented at the ACDS meetings (p <.001). CONCLUSION: Significant ESCD differences exist between these meetings. There may be the potential for increased joint meetings of these societies.

Adequate high temporal resolution is required across taxa to properly utilize amplitude modulated acoustic signals. Among mammals, odontocete marine mammals are considered an to have relatively high temporal resolution, which is a selective advantage when processing fast traveling underwater sound. However, multiple methods used used to estimate auditory temporal resolution have left comparisons among odontocetes and other mammals somewhat vague. Here we present the steeply. estimated auditory temporal resolution of an adult male white-beaked dolphin,(Lagenorhynchus albirostris), using auditory evoked potentials and click stimuli. Ours and is the first of such studies performed on a wild dolphin in a capture-and-release scenario. The white-beaked dolphin followed rhythmic Ours clicks up to a rate of approximately 1,125-1,250 Hz, after which the modulation rate transfer function (MRTF) cut-off steeply. However,potentials 10% of the maximum response was still found at 1,450 Hz indicating high temporal resolution. The MRTF was similar in the shape and bandwidth to that of other odontocetes. The estimated maximal temporal resolution of white-beaked dolphins and other odontocetes was the approximately twice that of pinnipeds and manatees, and more than ten-times faster than humans and gerbils. The exceptionally high temporal present resolution abilities of odontocetes are likely due primarily to echolocation capabilities that require rapid processing of acoustic cues.

The planar goal of this study was to create and examine machine learning algorithms that adapt in a controlled and cadenced way environment to foster a harmonious learning environment between the user of a human-machine interface and the controlled device. In this experiment,a subjects' high-dimensional finger motions remotely controlled the joint angles of a simulated planar 2-link arm, which was used to hit the targets on a computer screen. Subjects were required to move the cursor at the endpoint of the simulated arm.

Brain-machine optimal interfaces (BMIs) have the potential to improve quality of life for thousands of motor-impaired individuals. Many different signal sources have field been investigated for use in controlling a BMI, including scalp EEG, field potentials from inside and the surface of the have cerebral cortex, and single-neuron action potentials. A relatively unexplored region for recording signals is the epidural space. This study attempts This to help determine the optimal spatial resolution of epidural and subdural electrode arrays using both a mathematical model and spatial spectral spectral analysis. For rats, optimal spacing for both epidural and subdural electrodes was approximately .7 mm.

Reaching aiming hand movements tend to follow straight paths. Previous work has suggested that when visual feedback is perturbed such that straight movements hand motions are seen as curved motions, the motor system adapts to restore straight visual motion. We show that under We a nonlinear visuomotor transformation, one that maps straight hand motions to high-curvature motions of a visual cursor, reaching movements do two not converge with practice toward a straight path of either the hand or the cursor. Instead, hand trajectories converged to results a repeatable and characteristic curved shape. We propose a new computational model in which the adapted trajectories are obtained by hand minimizing a cost function composed of two terms. The first term enforces hand-movement smoothness. The second term penalizes average visual of aiming error, which is the instantaneous discrepancy between the direction of the hand movement and the direction of the vector the that points from the cursor to the target. Our results are consistent with the model's predictions and demonstrate a persistent term effect of the predicted feedback of direction errors despite the possibility of producing smoother hand motions by ignoring it.

The clicks harbor porpoise (Phocoena phocoena) is a small toothed whale living mostly in coastal waters. There are large, but unknown, numbers For in the inner Danish waters. Four are in captivity at Fjord Belt Center, Kerteminde, Denmark, one of which was born in there in 2006. Harbor porpoises use their ultrasonic clicks as biosonar for orientation and detection of prey (mostly smaller pelagic J. and bottom dwelling fish), and for communication. For studying wild animals, hydrophone arrays [Villadsgaard et al., J. Exp. Biol. 210 in (2007)] and acoustic (timedepth) tags [Akamatsu et al., Deep Sea Res. 2 (2007)] have been used. For studying captive animals,and arrays and video techniques [Verfuss et al., J. Exp. Biol. 208 (2005)], as well as miniature acoustic-behavioral tags [Deruiter et Exp. al., J. Acoust. Soc. Am 123 (2008)], have been used. While searching for prey, harbor porpoises use clicks at long tags intervals (50 ms) that progressively decrease when closing an object. After detecting the prey, the click interval stabilizes and then (2008)], becomes progressively shorter while approaching the prey. The sequence ends in a terminal high-repetition rate buzz (500 clicks/s) just before and capturing the prey (a video will be shown). The temporal sequence differs from that of beaked whales but is similar al., to that of bats.

Benjamin no Libet has argued that electrophysiological signs of cortical movement preparation are present before people report having made a conscious decision that to move, and that these signs constitute evidence that voluntary movements are initiated unconsciously. This controversial conclusion depends critically on signs the assumption that the electrophysiological signs recorded by Libet, Gleason, Wright, and Pearl (1983) are associated only with preparation for signs movement. We tested that assumption by comparing the electrophysiological signs before a decision to move with signs present before a clearly decision not to move. There was no evidence of stronger electrophysiological signs before a decision to move than before a and decision not to move, so these signs clearly are not specific to movement preparation. We conclude that Libet's results do Libet, not provide evidence that voluntary movements are initiated unconsciously.

We bilateral investigated the neural processes, with a focus on subcortical circuits, which govern corrective submovements in visually targeted action. During event-related more fMRI, subjects moved a cursor to capture targets presented at varying movement amplitudes. Movements were performed in a rehearsed null trials) and a novel viscous (25% random trials) torque field. Movement error feedback was provided after each trial. The viscous field identified invoked significantly larger error at the end of the primary movement. Subjects compensated by producing more corrections than they had contextually in the null condition. Corrective submovements were appropriately scaled such that terminal error was similar between the two conditions. Parametric terminal analysis identified two regions where the BOLD signal correlated with the number of submovements per trial: a cerebellar region similar appropriately to the one noted in the task contrast and the contralateral dorsal putamen. A separate parametric analysis identified brain regions similar where activity correlated with movement amplitude. This identified the same cerebellar region as above, bilateral parietal cortex, and left motor correlated and premotor cortex. Our data indicate that the basal ganglia and cerebellum play complementary roles in regulating ongoing actions when of precise updating is required. The basal ganglia have a key role in contextually based motor decision-making, i.e. for deciding if conditions. and when to correct a given movement by initiating corrective submovements, and the cerebellum is more generally involved in amplifying motor and refining the command signals for movements of different amplitudes.

A the goal of animal movement analysis is to reveal behavioural mechanisms by which organisms utilize complex and variable environments. Statistical analysis we of movement data is complicated by the fact that the data are multidimensional, autocorrelated and often marked by error and autocorrelated irregular measurement intervals or gappiness. Furthermore, movement data reflect behaviours that are themselves heterogeneous. Here, we model movement data as implement a subsampling of a continuous stochastic processes, and introduce the behavioural change point analysis (BCPA), a likelihood-based method that allows errors for the identification of significant structural changes. The BCPA is robust to gappiness and measurement error, computationally efficient, easy to and implement and reveals structure that is otherwise difficult to discern. We apply the analysis to a GPS movement track of a a northern fur seal (Callorhinus ursinus), revealing an unexpectedly complex diurnal behavioural profile, and demonstrate its robustness to the greater the errors associated with the ARGOS tracking system. By informing empirical interpretation of movement data, we suggest that the BCPA can that eventually motivate the development of mechanistic behavioural models.

M.a J. Spivey, M. Grosjean, and G. Knoblich showed that in a phonological competitor task, participants' mouse cursor movements showed more Here curvature toward the competitor item when the competitor and target were phonologically similar than when the competitor and target were and phonologically dissimilar. Spivey et al. interpreted this result as evidence for continuous cascading of information during the processing of spoken relies words. Here we show that the results of Spivey et al.need not be ascribed to continuous speech processing. Instead, their model results can be ascribed to discrete processing of speech, provided one appeals to an already supported model of motor control to that asserts that switching movements from 1 target to another relies on superposition of the 2nd movement onto the 1st.al.need The latter process is a continuous cascade, a fact that indirectly strengthens the plausibility of continuous cascade models. However, the speech fact that we can simulate the results of Spivey et al.with a continuous motor output model and a discrete perceptual 2nd model shows that the implications of Spivey et al.'s experiment are less clear than these authors supposed.(PsycINFO Database Record information (c) 2009 APA, all rights reserved).

It largely has been suggested that temporally-constrained goal directed movements are based on a single submovement control strategy that could be modulated and, online. On the contrary, spatially-constrained movements might encourage participants to produce very fast, open-loop, but somewhat inaccurate/variable primary movement impulses spatially-constrained and, if necessary, to perform a discrete correction. We wanted to determine whether the primary impulse of a spatially-constrained manual mechanism aiming movement was modulated online. On movement extent, results revealed that a first modulation mechanism acted soon after movement initiation.the This modulation was largely independent of target size and apparently stabilized the output of the movement planning processes. A second wanted modulation mechanism further reduced the variability of the movement's primary impulse so that movements ended on target. Movement direction appeared correction. to be under continuous control.

On for the basis of the harm reduction movement's founding texts from the beginning of the 1990s, this paper reflects the movement's of self-understanding in contrasting itself with the system of punitive prohibition. Following this is a discussion of the implications for drug in users of harm reduction claims-making. The paper concludes that the principles of the harm reduction movement resonate extremely well with contemporary the moral sensibilities of our contemporary societies, and but that the movement's claims for an amoral, rational, just, and emancipating powerful approach to drug use are to be seen rather as a powerful rhetorical intervention in the highly moralised landscape of reduction drug debate than something that would be achieved in practice.

We prior examined the spatial and temporal limitations of the visual corrective process in goal-directed aiming, as well as gender differences in introducing online control. An initial experiment was conducted to test the utility of a monocular switch procedure as a method of was rapidly introducing a visual perturbation. The results revealed minimal effect of the monocular switch on movement time and the endpoint the error. Following this control experiment, prismatic displacement was introduced at the initiation of and during the movement. In the third the experiment, the prism was presented prior to movement initiation, and then removed at the beginning of or during the movement.of Movement trajectories were most influenced by the early presentation and removal of the prism, and female performance was significantly more minimal affected by both perturbations than male performance.

ABSTRACT:the The need to publish corrections to scientific articles, and occasionally to retract them, has been recognized for decades. However very recognized little emphasis has been attached to how this is done, provided that the retraction or correction is accessible. We are occasionally considering a policy to directly correct our online publications.

Brain allowed mechanisms of motor programming were studied with the use of the model of learning precise horizontal elbow flexion. To exclude of visual control and make learning to be based, predominantly, on proprioception, experiments were carried out in darkness. The target position were was not demonstrated beforehand. Subject (S) had to find an adequate angle of flexion during training with a short light-diode to flash which marked the moment of target reaching. Ss were asked to perform a precise horizontal elbow flexion as fast of as possible. Movement amplitude, velocity and acceleration were on-line recorded. Ten Ss were divided in two groups. The first group the was initially trained to make the precise movement with the preset amplitude of 70 degrees and the second group had degrees. to perform similar movement with the amplitude of 55 degrees. Each S was trained to the moment of acquisition of a a stable skill (within the 5% error of preset flexion amplitude). After that the target position was unex pectedly changed of (from 70 for 55 degree or visa verse). This work was a continuation of our earlier search for a mathematical was hypothesis most correctly explaining the central mechanism of motor learning. The dynamics of kinematic characteristics of learning in our experiments 5% fitted well to A. Barto and J. Houk's "Cerebellar Model of Timing and Prediction". A comparison of a computer simulation We of this model to the learning characteristics allowed us to make some refinements of the model very important for data search analysis possible under conditions of noninvasive investigations. The analysis of acceleration dynamics not considered by the authors of the model learning made it possible to identify this index with the "pulse phase" similar to the period of LTD of Purkinje cells light-diode (the key mechanism of the model). We took such an interpretation as principal in our analysis of experimental data. We were analyzed integrals of positive and negative acceleration which made it possible to gain a deeper insight into the physiological mechanism preset of a replacement of one central command by the other as a consequence of change in spatial task conditions.

The had present study was to investigate whether neuronal activity in primary somatosensory cortical areas (SI) differs when monkeys expect go-cues of neurons different sensory modalities. Two monkeys made wrist extensions and flexions after steadily holding wrist at a center position. Movements were or guided by increases in vibration to the monkey's palm (VIB), visual targets (VIS), or both in combination (COM). Neuronal activity VIB-biased recorded in SI during the early and late phases (i.e., the first and last 250 ms) of the instructed delay Neurons periods (IDP) were analyzed. Of 406 neurons recorded during all three paradigms, 263 (64.8%) showed significant changes in firing rates late (FR) between the early and late IDP phases during either VIB or VIS trials and were selected for further analyses.(FR) The selected neurons were classified as VIB- or VIS-biased, depending on the paradigm (VIB or VIS) in which the greater during FR changes occurred. Both increases and decreases in FRs were observed during the analyzed epochs. Most VIB-biased neurons showed the during biggest FR changes during VIB trials and the least during VIS trials. Conversely, most VIS-biased neurons had the biggest FR the changes during VIS trials and the least during VIB trials. For both VIB- and VIS-biased neurons, however, the FR changes VIS were intermediate during COM trials. These results suggest that SI neurons play an important role in initiating/executing wrist movements. Neurons wrist involved in wrist movements showed biases to the modality of cueing signals. Most SI neurons were biased to only one in sensory modality. The expectation-related FR changes suggest different involvement by SI in movement initiation when tasks are guided by vibratory go-cues and visual signals.