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La letteratura non ha ancora chiarito quale sia il ruolo dei movimenti oculari nella percezione del movimento in assenza di possibilità di inseguimento degli stimoli. In questo studio abbiamo registrato i movimenti oculari di quaranta partecipanti durante un compito di «motion coherence» che impediva l’inseguimento, per indagare se e in che modo i movimenti oculari contribuissero all’accuratezza nella percezione del movimento. L’abilità di discriminare la direzione del movimento è stata studiata in funzione della velocità dei movimenti oculari misurati mediante videoculografo a infrarossi. I risultati confermano che la velocità dei movimenti oculari predice l’accuratezza nella percezione del movimento. Ciò fa supporre che sussista un processo iniziale che accomuna i sistemi atti a governare i movimenti oculari e la percezione del movimento.

Patients with mild traumatic brain injuries (mTBI) often report difficulties in motor coordination and visuo-spatial attention. However, the consequences of mTBI on fine motor and visuo-motor coordination are still not well understood. We aimed to evaluate whether mTBI had a concomitant effect on fine motor ability and visuo-motor integration and whether this is related to visual perception and visuo-spatial attention impairments, including patients at different symptoms stage. Eleven mTBI patients (mean age 22.8 years) and ten healthy controls participated in the study. Visuo-motor integration of fine motor abilities and form recognition were measured with the Beery-Buktenica Developmental Test of Visual-Motor Integration test, motion perception was evaluated with motion coherence test, critical flicker fusion was measured with Pocket CFF tester. Visuo-spatial was assessed with the Ruff 2 & 7 Selection Attention Test. mTBI patients showed reduced visuo-motor integration, form recognition, and motor deficits as well as visuo-spatial attention impairment, while motion perception and critical flicker fusion were not impaired. These preliminary findings suggest that the temporary brain insults deriving from mTBI compromise fine motor skills, visuomotor integration, form recognition, and visuo-spatial attention. The impairment in visuo-motor coordination was associated with speed in visuo-attention and correlated with symptoms severity while motor ability was correlated with time since concussion. Given the strong correlation between visuomotor coordination and symptom severity, further investigation with a larger sample seems warranted. Since there appeared to be differences in motor skills with respect to symptom stage, further research is needed to investigate symptom profiles associated with visuomotor coordination and fine motor deficits in mTBI patients.

Literature on the development of global motion and global form perception demonstrated their asynchronous developmental trajectories. However, former studies have failed to clearly establish the critical period of maturation for these specific abilities. This study aimed to analyze the developmental trajectories of global motion and global form discrimination abilities by controlling for basic visual functions and general cognitive ability and to present the global motion and global form normative scores. A sample of 456 children and adolescents (4–17 years of age) and 76 adults recruited from the Italian and Swedish general population participated in the study. Motion and form perception were evaluated by the motion coherence test and form coherence test, respectively. Raven’s matrices were used to assess general cognitive ability, the Lea Hyvarinen chart test was used for full- and low-contrast visual acuity, and the TNO test was used for stereopsis. General cognitive ability and basic visual functions were strongly related to motion and form perception development. Global motion perception had an accelerated maturation compared with global form perception. For motion perception, an analysis of the oblique effect’s development showed that it is present at 4 years of age. The standardized scores of global motion and form coherence tests can be used for clinical purposes.

This population-based study evaluated motion and form perception in 71 children born extreme premature (EPT; < 27 gestational weeks), aged 6.5 years, as compared to a matched group of 79 control children born at term. Motion and form perception were evaluated by motion coherence and form coherence tests. The EPT group showed a poorer performance on both tasks as compared to the control group. However, after controlling for IQ and visual acuity, the EPT group showed only a significant deficit in motion perception. No association was found between motion perception accuracy and gestational age, previous retinopathy of prematurity, or previous intraventricular hemorrhage in the EPT group. The results highlight the long-term motion perception deficits in children born EPT.

Procura-se, neste texto, analisar o conhecido episódio final do Banquete de Platão, no qual Alcibíades descreve a figura de Sócrates. O objetivo é mostrar semelhanças com o discurso socrático na Apologia e a intenção platônica de retomar, em novos termos filosóficos, a defesa de seu mestre contra a acusação de corromper os jovens.

Since family context is considered to be an important environmental factor for the attitude of children towards eating, the perception of psychological distress in children and the parental perception of child behavioural and emotional problems were investigated. School-age children (n = 665; 8–11 years of age), selected from different schools, were classified into weight categories according to their BMI. The children completed the Self-Administrated Psychiatric Scales for Children and Adolescents and their parents completed the Child Behaviour Checklist. Obese children reported more psychological distress compared to the other children, while their parents did not show a greater perception of emotional problems, compared to parents of normal-weight children. This suggests that the psychological distress of obese children might not be recognised by their parents. Our results highlight the role of this lack of parental awareness in child development, and in the progress of the psychological distress related to eating problems.

Aim: To evaluate the visual magnocellular pathway by a coherent motion perception test in children with foetal alcohol syndrome (FAS). Methods: Eighty-nine children (49 with verified FAS and 40 without FAS) aged from 10 to 16 years were included into the study. Both the study and the control group were children living in orphanages. A coherent motion perception test was used. The test consisted of 150 white moving dots on a black background presented in different signal-to-noise ratio conditions. The task was direction detection of the coherently moving dots whose percentage decreased at each step. Results: A significant difference between the two groups was found (p = 0.018). Children with FAS had lower coherent motion perception ability in all the signal-to-noise ratio conditions. A significant difference between difficulty levels (p

A slow oscillatory movement (SOM) has previously been discovered superimposed on the three well known components of fixational eye movements. The purpose of the present study was to explore the visual influence on the control mechanism of the SOM. Three tests with different fixation targets and backgrounds were prepared. The eye position during a fixation task on healthy test subjects has been recorded by the Chronos eye tracking device. The visual stimuli with no or less information triggered larger SOM amplitudes. None of the investigated conditions significantly influenced on SOM frequency.

A slow oscillatory eye movement was discovered in a 20-min-long recording. The frequency of this slow oscillation was lower than any known eye movement. Fixational eye movements were recorded in seven healthy subjects with four different recording techniques and with different sampling frequencies. The frequency of the oscillation is 0.04-0.10 Hz, and the amplitude is less than 0.2°. Right and left eyes oscillate conjugately in the vertical direction implying a neural control. We suggest the oscillation to be a fourth movement in the fixational eye movement system. The influence of the oscillation on visual function is not known nor the underlying mechanism controlling the eye movement.

Given the paucity of prospective randomized controlled trials assessing comparative performances of different dialysis techniques, we compared on-line high-flux hemofiltration (HF) with ultrapure low-flux hemodialysis (HD), assessing survival and morbidity in patients with end-stage renal disease (ESRD).An investigator-driven, prospective, multicenter, 3-year-follow-up, centrally randomized study with no blinding and based on the intention-to-treat principle.Prevalent patients with ESRD (age, 16 to 80 years; vintage6 months) receiving renal replacement therapy at 20 Italian dialysis centers.Patients were centrally randomly assigned to HD (n = 32) or HF (n = 32).All-cause mortality, hospitalization rate for any cause, prevalence of dialysis hypotension, standard biochemical indexes, and nutritional status. Analyses were performed using the multivariate analysis of variance and Cox proportional hazard method.There was significant improvement in survival with HF compared with HD (78%, HF versus 57%, HD) at 3 years of follow-up after allowing for the effects of age (P = 0.05). End-of-treatment Kt/V was significantly higher with HD (1.42 +/- 0.06 versus 1.07 +/- 0.06 with HF), whereas beta(2)-microglobulin levels remained constant in HD patients (33.90 +/- 2.94 mg/dL at baseline and 36.90 +/- 5.06 mg/dL at 3 years), but decreased significantly in HF patients (30.02 +/- 3.54 mg/dL at baseline versus 23.9 +/- 1.77 mg/dL; P0.05). The number of hospitalization events for each patient was not significantly different (2.36 +/- 0.41 versus 1.94 +/- 0.33 events), whereas length of stay proved to be significantly shorter in HF patients compared with HD patients (P0.001). End-of-treatment body mass index decreased in HD patients, but increased in HF patients. Throughout the study period, the difference in trends of intradialytic acute hypotension was statistically significant, with a clear decrease in HF (P = 0.03).This is a small preliminary intervention study with a high dropout rate and problematic generalizability.On-line HF may improve survival independent of Kt/V in patients with ESRD, with a significant decrease in plasma beta(2)-microglobulin levels and increased body mass index. A larger study is required to confirm these results.

Purpose: Ocular motility disturbances are common in patients with thyroid-associated ophthalmopathy (TAO). A quantitative evaluation of the isometric force of the eye muscles in TAO might be useful in the detection of early stages of this disease. Methods: A total of 32 patients with TAO were divided into three groups according to whether they had mild active, pronounced, active, or longstanding, inactive disease. A group of six patients with Graves' disease without clinical signs of TAO and a group of 10 control subjects were also studied. The development of isometric force during saccadic eye movements of 5-, 10- and 20-degree amplitude in horizontal and vertical directions of gaze were recorded in the more affected eye in patients and the non-dominant eye in normal subjects, using a suction contact lens/strain gauge technique. Results: Peak tension (Fp) in vertical and horizontal saccadic movements was not significantly different between groups. Steady-state tension (Fs) was significantly higher in the groups with pronounced, active and longstanding, inactive disease than in the other groups for vertical (p

Background Assessment of changes in saccade velocity may be useful in the early detection of thyroid-associated ophthalmopathy (TAO). Two eye-tracking systems were used to measure the velocity of saccadic eye movements in patients with TAO. Method Fourteen patients with active TAO and 14 healthy controls were enrolled for recordings with two eye-tracking systems: the magnetic scleral search coil (MSC; Skalar Medical) and the infrared reflection systems (IR; Orbit XY-1000). The MSC is generally considered the "gold standard" method for tracking of rapid eye movements. The IR system uses novel computer technology and is based on sampling of reflected infrared light from the surface of the eyes. Main sequence plots constructed from the recorded saccadic peak velocity and amplitude were analyzed for differences between patients and healthy controls. Results There were no significant differences between patients with TAO and healthy controls in the constructed main sequence plots of maximum velocity (VMAX) and the slope constant (C). Conclusions Main sequence analysis of saccadic eye movements was not useful for detecting TAO in this experimental setting with either of the two eye-tracking methods. This is hypothesized to be due to compensation for the early orbital changes in TAO by neural adaptation of the saccades in the brain stem. The contradictory results between this and previous studies cannot be easily explained. We assume that there is a large heterogeneity in the saccadic eye movement performance in both the normal population and the TAO-population. Also, differences in the study design may cause dissimilar outcomes and hence incoherent conclusions. A non-invasive recording system that is able to generate a minimum amount of intra- and inter-individual variability and a study design where normal variability can be reduced to a minimum may be useful for future identification of early eye muscle changes in TAO.

This text intends to analyse a passage of Plato’s Republic III on kinds of poetry and elocution. Some variation in use of vocabulary relationed with idea of imitation ( mimesis ) is observed. This fact seems to introduce problems to understand the meaning and aims of the doctrine. I try to propose a way of explaining and solving that semantic variation, basing analysis on theses the dialogue has just established.

BACKGROUND: The infrared (IR) and the magnetic scleral search coil (MSC) systems for eye tracking were studied with regard to the intra-individual variability in saccadic eye movement recordings. METHOD: Three healthy subjects performed similar saccadic eye movement tasks at five different occasions with both the IR (Orbit XY-1000) and the MSC (Skalar Medical) techniques. The maximum velocity (VMAX) and slope constant (C) of the main sequence plots were analyzed with regard to the coefficient of variation (CV) and the intraclass correlation coefficient (Ricc). In addition, the possible reasons for variability in the IR recordings, especially different causes for noise, were analyzed and discussed. RESULTS: The main sequence data showed intra-individual variation with both recording systems, but the coefficient of variation was higher for VMAX with the IR compared to the MSC method. Ricc analysis showed that 36% of the variance of VMAX and 49% of the variance of C resulted from intra-individual variability in recordings of the IR system. The corresponding results for the MSC recordings regarding VMAX and C were 48% and 88%. CONCLUSIONS: Saccadic eye movement recordings yielded a larger intra-individual variability with the IR system than with the MSC system. The effect that the MSC annulus may have on the ocular motor command signal and the possible low pass filter caused by the coil slipping on the surface of the eye may partly explain the relatively lower velocity in the MSC recordings. Also, noise in the IR recordings induces peaks of eye velocity, which can be reduced considerably by filtering. However, the variability in the recordings, which was larger in the IR than in the MSC recordings, did not seem to be decreased by filtering. The basic level of noise in the recordings was not clearly associated with the amount of reduction of VMAX when the IR recordings were filtered. We suggest that artefacts of the saccadic signal, which can be related to changes in the reflecting surface of the eyes and eyelids, are important factors for explaining the variability and high-velocity peaks in the IR recordings. Lighting conditions was confirmed as a cause for noise, but temperature and air humidity changes in the goggles were not suspected to influence data in the normal experimental setting. Although noise, shortcomings of the recording technique and procedure may offer explanations for the intra-individual variability, the calibration procedure and changes in attention and fatigue of the subject should also be considered.

Este texto pretende fazer algumas observações introdutórias à Filosofia, tentando mostrar que, não sendo uma forma de encontrar respostas prontas para problemas pessoais, ela consiste, sobretudo, numa atividade de pensamento sempre renovada e crítica.

A decreasing drift of the counter-rolled eye position (OCR) during head tilt was recently described. The underlying mechanism is not known. OCR in eleven healthy subjects was recorded (Search coil, Skalar) during a head tilt paradigm in two test conditions. The head was tilted with a velocity below (test 1) and above (test 2) detection threshold for the semicircular canals (SC) and held static for eight minutes. A significant drift of OCR was revealed in test 2 (P = .0006, ANOVA) and close to significant in test 1 (P = .07). No statistical difference was found between the two test conditions. The results suggest that the OCR drift was not caused by the SC complex merely.

Introduction: β-Blockers have been shown to be effective in the treatment of both arterial hypertension and heart failure. However, slow titration of β-blockers over several weeks and rigorous supervision are essential to minimise antiadrenergic adverse effects in patients with heart failure. α1-Blockers are well tolerated and effectively lower blood pressure by reducing peripheral resistance. Patients and methods: This study assessed changes in left ventricular function and quality of life in hypertensive patients with mild heart failure treated with enalapril and furosemide combined with a β-blocker with peripheral vasodilating activity (carvedilol) or an α-blocker (doxazosin), over a 1-year period. Sixty patients aged 45–65 years with untreated essential arterial hypertension and mild heart failure were randomised to receive enalapril + furosemide in combination with carvedilol or doxazosin. Results: In the carvedilol compared with the doxazosin group, ejection fraction diminished significantly (38% vs 42%, p < 0.05) and quality of life worsened significantly (Minnesota Living Heart Failure score 54 vs 47, p < 0.05) during the first 3 weeks of treatment. Ejection fraction and quality of life had significantly improved from baseline in both groups by 12 months. Conclusion: Doxazosin in combination antihypertensive therapy rapidly improves clinical status and haemodynamics in hypertensive patients with mild heart failure by reducing afterload. After 1 year, doxazosin and carvedilol improve clinical and haemodynamic parameters.

Este texto pretende apresentar e comentar as principais características da filosofia socrática, tal como elaborada em diálogos platônicos, que permitem compreender em que sentido essa filosofia pode ser vista como uma forma de ensino e aprendizado.

The validity of informant- based techniques has been established for the detection of dementia cases by non-pathological individuals, but is still controversial for the assessment of the severity of dementia. This study aimed at ascertaining whether informant- based evaluation (the so-called informant report) of the cognitive and behavioral impairment of a patient is valid for grading the severity of dementia, and consistent with objective assessment of the patient’s cognitive and behavioral functioning. We enrolled 96 community-dwelling outpatients and 56 controls assessed at the Geriatric Evaluation Unit of the University of Modena, Italy. All patients scored lower than 27 on the MMSE, and met DSM-IV inclusion criteria for Alzheimer’s dementia. Patients and controls were administered the CAMDEX interview, containing a section which collects participant (patient or control) and informant evaluations on dementiarelated cognitive and behavioral deficits. The informant report resulted effective at MANOVA for grading the severity of dementia in 4 of its 5 measures (namely, memory, everyday activities, general mental functioning and depressed mood), and was correlated with the scores of several scales of the CAMDEX cognitive section (i.e., CAMCOG). Instead, the participant’s (patient or control) report showed a lower capacity for grading dementia, and was poorly correlated with the psychometric outcomes of cognitive functioning. On the whole, the results corroborated the validity of the informant report in the diagnostic work-up for grading dementia, given its sensitivity to the severity of dementia, and its consistency with cognitive psychometric outcomes.

A statistical analysis was performed on the possible influence of injection sites on botulinum toxin A (BAT) treatment of essential blepharospasm. For this purpose, two groups (a total of 60 patients) were evaluated. The first group was treated with three suprabrow injections and the second one with five lid injections. The amount of BAT was the same in the two groups. Clinical results of the two different techniques appeared to be superimposable. Potentially, lid injection may induce more side effects. This was not, however, noted in our study. This is the first comparative study on the role of injection sites for BAT.

Trata-se de considerar o tema das semelhanças e diferenças entre ceticismo acadêmico e ceticismo pirrônico, para mostrar que as semelhanças, diferentemente do que sustenta parte importante da tradição historiográfica e filosófica, permitem encontrar nos acadêmicos um ceticsmo legítimo. Ao mesmo tempo, busca-se sugerir que as diferenças autorizam uma aproximação entre os acadêmicos e a filosofia moderna, pela via de ua de suas ideias fundamentais: a de subjetividade.

PURPOSE: Slow oscillatory eye movements (SOMs) occur simultaneously with tremor, drifts, and microsaccades during visual fixation. In a previous study, the amplitude of SOM was found to be affected by the visual characteristics of the stimuli. This indicates a perceptual influence on the control of the movement. However, the frequency of SOM did not change. The aim of our study was to investigate how SOM is affected by extraocular muscle tension. METHODS: In a repeated-measurement experiment, 14 subjects were instructed to maintain fixation for 3 minutes on a bright dot presented at four distances (15, 30, 60, and 120 cm). The level of extraocular muscle tension is assumed to increase with decreased fixation distance due to convergence angle. Eye movements were recorded binocularly using a video eye tracker, and the amplitude and frequency of SOM for each eye were obtained by independently filtering the horizontal and vertical eye position signals with a discrete Fourier transformation. RESULTS: The results showed no significant differences for the amplitude. However, the horizontal frequency was found to be significantly lower at the closest distance. No significant differences were found for the vertical frequency. CONCLUSIONS: Based on these findings we conclude that extraocular muscle tension does have an effect on the frequency, but not the amplitude, of the oscillations. The apparent double dissociation between perceptual effects on amplitude versus muscle tension effects on frequency is discussed in relation to the origin and control of SOM.

Este texto pretende desenvolver a tese de que o principal interlocutor de Sócrates em A República, Glauco, irmão de Platão, revela qualidades semelhantes àquelas que serão exigidas dos guardiões e do futuro filósofo e governante da cidade construída na argumentação de Sócrates e seus interlocutores. Procura-se mostrar que isso pode ser encontrado em diversos momentos do diálogo. Pretende-se também extrair algumas consequências para a própria compreensão desse diálogo e da filosofia platônica como um todo.

O presente texto procura mostrar que o discurso cético, mais especificamente o discuso cético pirrônico, se lido a partir de seu "tempo lógico", revela a presença de dificuldades semelhantes às que se podem encontrar nas filosofias dogmáticas. Para isso, analisam-se algumas passagens de Sexto Empírico e de Oswaldo Porchat, bem como a noção de suspensão de juízo (epokhé).

Children and adults can approximate numbers of items, compare these approximations, and perform approximate arithmetic operations via a non-symbolic, pre-linguistic system called the Approximate Number System (ANS). Studies using neuroimaging techniques demonstrated the role of the parietal cortex in decoding both non-symbolic and symbolic quantity. Although it has been proven that the parietal regions are involved also in visual processing such as coherence motion perception, little is known about the relationship between these visual processes and the ANS. The aim of this study is to investigate whether the acuity in the ANS is related to dorsal and/or ventral visual functions. A sample of sixty-five typical development children (age 6-10 years; 42 males and 23 females) took part in the experiment. ANS acuity was measured using a numerical discrimination task (Halberda et al., 2008) in which participants were briefly shown arrays of yellow and blue dots and had to identify the more numerous array; a motion coherence test and a form coherence test were applied to evaluate dorsal and ventral stream functions respectively. In the motion test participants were asked to detect the direction of moving dots, in the form test participants had to recognize a form created by spatially aligned dots. We found significant correlations between ANS acuity and motion perception ability (p=0.014) as well as form discrimination ability (p=0.047). More specifically, higher performance in the motion and form tests are related to higher ANS acuity. The effect size values show that the magnitude of the relationship with the ANS was higher for the motion (partial η2=0.09) than for the form coherence test (partial η2=0.06). These results demonstrate that both dorsal and ventral visual processing influence ANS acuity but that the association between ANS and dorsal stream processing is slightly stronger.

Citicoline has been used to improve consciousness levels in cerebral trauma and as a complement for levodopa in Parkinson's disease. It has also been shown that severe glaucomatous visual field deficits improve for at least 4 months with the use of citicoline. In this paper, preliminary results are presented of an open and a double-blind study on the effect of citicoline in amblyopia.The open study was started in 1991. Fifty patients with amblyopia were treated with citicoline (1000 mg i.m. daily for 15 days). They were selected from an age group beyond the plastic period of the visual system. Occlusion or other types of anti-amblyopic treatment were never used at the same time as citicoline. A double-blind study was conducted on 10 more patients, randomly assigned to a treatment or placebo group and followed for 6 months. A statistical test for repeated measures was performed on all the results.A statistically significant improvement in visual acuity was found both for the amblyopic and the sound eye in 46 of the 50 patients (92%). The behaviour was different for normal and amblyopic eyes. The improvement remained stable for at least 4 months. These results have been substantiated by the double-blind study. No side effects were observed.Citicoline improves visual acuity, at least temporarily, in amblyopic patients beyond the plastic period of the visual system. Our results suggest that trials of citicoline as a medical treatment of amblyopia are warranted.

Purpose: To establish whether or not the dynamics of saccadic eye movements are significantly changed in patients with different stages of thyroid-associated ophthalmopathy (TAO) and, subsequently, if analysis of saccades could serve as an additional diagnostic tool for early detection of inflammatory activity in TAO. Methods: Thirty-seven patients with TAO and 10 age- and gender-matched control subjects were investigated. The patients were divided into four groups according to the stage of the disease: (i) early mild disease (n = 10), (ii) early severe disease (n = 11), (iii) long-standing restrictive disease (n = 10) and (iv) proven auto-immune hyperthyroidism without any signs of TAO (n = 6). Horizontal and vertical saccades with amplitudes of 10°, 20°, 30° and 40° were recorded binocularly using the induction scleral search coil technique. The two main sequence constants Vmax and C were calculated for each eye. Repeated measurement analysis of variance was carried out to test for differences between different gaze directions, eyes and groups. Results: In horizontal saccades, significant differences were found between groups but not between abduction and adduction. In vertical saccades, differences between groups and the interaction between groups and up- and down-gaze saccades were significant. Compared with the control group, analysis of the main sequence curves revealed larger differences in patients of group 3 and 4 than in those of group 1 and 2. Whereas in the control group down-gaze saccades were faster than up-gaze saccades, the opposite behaviour was found in all patient groups. The largest differences were detected among those patients who had no signs of TAO (group 4). Conclusions: In this study, significant saccade differences were detected in all patients with TAO. In contrast to our earlier studies where evaluation of multiple individual saccade parameters did not reveal significant differences, analysis of the main sequence constants and mathematical reconstruction of the main sequence curves turned out to be a sensitive technique for reliable detection of subtle ocular motility changes. Significant differences were detected even in patients with auto-immune thyroiditis where no clinical signs of TAO were apparent.

Este texto pretende apresentar, de forma sucinta, um conjunto de estratégias de filósofos modernos para a retomada e crítica do ceticismo antigo, procurando destacar algumas semelhanças e diferenças This text intends to present briefly some strategies adopted by modern philosophers for reception and criticism of ancient skepticism, and to remark some resemblances and differences

Reading acquisition requires, in addition to appropriate phonological abilities, accurate and rapid selection of sublexical orthographic units by attentional letter string parsing. Spatio-temporal distribution of attentional engagement onto 3-pseudoletter strings was studied in 28 dyslexic and 55 normally reading children by measuring attentional masking (AM). AM refers to an impaired identification of the first of two sequentially presented masked objects (O1 and O2). In the present study, O1 was always centrally displayed, whereas the location of O2 (central or lateral) and the O1–O2 interval were manipulated. Dyslexic children showed a larger AM at the shortest O1–O2 interval and a sluggish AM recovery at the longest O1–O2 interval, as well as an abnormal lateral AM. More importantly, these spatio-temporal deficits of attentional engagement were selectively present in dyslexics with poor phonological decoding skills. Our results suggest that an inefficient spatio-temporal distribution of attentional engagement – probably linked to a parietal lobule dysfunction – might selectively impair the letter string parsing mechanism during phonological decoding.

The magnitude of the association between developmental dyslexia (DD) and motion sensitivity is evaluated in 35 studies, which investigated coherence motion perception in DD. A first analysis is conducted on the differences between DD groups and age-matched control (C) groups. In a second analysis, the relationship between motion coherence threshold and reading ability is considered. Globally, the mean effect size (ES) is moderate (d = 0.675, 2334 subjects) with a large value (d = 0.747) for the between-groups differences in motion perception and a smaller mean ES (d = 0.178) for the correlational studies. The influence on ES of the stimuli parameters and subjects age is analyzed. The number of dots, the age of the subjects, and the type of analysis (i.e. between-group or correlational) are significantly related to the ES. Looking at the ES values, a smaller number of dots constituting the stimuli are associated with larger ES and, interestingly, the children studies are associated with lower ES in comparison with the researches evaluating adults. The large ES value supports the importance of studying motion perception deficits in DD groups, consistently with the claim that dorsal impairment/noise-exclusion deficit could be one of the risk factor of reading difficulties. Copyright © 2010 John Wiley & Sons, Ltd.

Although developmental dyslexia (DD) is frequently associate to a linguistic deficit, the underlying neurobiological cause remains unclear. One prominent vision science hypothesis suggests a specific deficit in magnocellular (M) pathway in DD. However, a recent hypothesis proposes that M-deficits contribute to the etiology of phonological decoding ability (i.e., new word and nonword reading), impairing selectively the attentional orienting process onto letter string. Thus, a specific M-pathway impairment in association with an attentional orienting disorder in DD children with phonological decoding deficit was specifically predicted by this neurobiological hypothesis. In the present study we investigated the M-pathway and attentional orienting in 18 dyslexic (10 with phonological decoding deficit) and in 29 chronological age and IQ matched normally reading children by measuring dynamic stimuli sensibility (i.e., spatial frequency doubling illusion) and the time-course of automatic covert attention (i.e., target detection effect at different SOAs of a non-predictive and peripheral spatial cue), respectively. The results showed a specific deficit of the M-pathway task in dyslexic with phonological decoding deficit. More importantly, the same group of dyslexics with M-deficit presented a sluggish attentional orienting: attentional facilitation was present at longer cue-target SOAs compared with normal readers. These results highlight that a M-deficit linked to a parietal-attentional dysfunction might impair the phonological decoding mechanisms that are critical for reading acquisition.

Acta Ophthalmol. 2010: 88: 872–876 Abstract. Purpose: Succinylcholine (Sch) can induce contracture in slow, multiply innervated muscle fibres of the extraocular muscles in animals of different species. Slow muscle fibres also exist in human eye muscle but their physiological properties have not been studied. Methods: Isometric tension development was recorded in the lateral and medial rectus muscles in 12 patients operated under general anaesthesia. A strain gauge probe was attached with 5−0 silk sutures to the muscle tendon. Recordings were made in 12 eye muscles with the tendon attached to the globe and in four muscles detached from the globe. Muscle activation was produced by i.v. injection of Sch at a dose of 0.2–0.3 mg/kg bodyweight. Results: A single injection of Sch induced slow contractures lasting for several minutes. In the muscles attached to the globe, mean maximal isometric tension was 12.2 g in the lateral rectus and 12.8 g in the medial rectus. Similar tension was shown in the muscles detached from the globe. Conclusions: The contracture of eye muscles in response to Sch showed characteristics typical of slow muscle fibre activation in amphibian and avian muscle and confirmed the participation of slow fibre systems in ocular motor control.

Recent evidence indicates that the 2nd harmonics of steady-state (8 Hz) electroretinograms to either sinusoidal flicker (FERG) or to counterphased gratings (PERG) presented in the macular region (9 degrees) represent different subsets of generators in the inner retina. We evaluated the steady-state macular FERG and PERG 2nd harmonics (2F and 2P, respectively) in 19 normal subjects (19 eyes) and in 23 multiple sclerosis patients (44 eyes; 25 eyes with a history of clinical optic neuritis, and 19 eyes with no history of optic neuritis, subclinical eyes). The mean 2F and 2P amplitudes were significantly reduced, as compared to controls, in both subclinical and optic neuritis eyes. The 2P phase was significantly delayed, as compared to controls, in subclinical eyes, whereas 2F phase was delayed in eyes with optic neuritis. 2F was outside the 95% confidence limits (in amplitude or phase) in 11/19 subclinical eyes and in 25/25 optic neuritis eyes. 2P was outside the normal range in 12/19 subclinical eyes and in 24/25 optic neuritis eyes. These results show that FERG and PERG 2nd harmonics are significantly altered in multiple sclerosis eyes with or without a clinical history of optic neuritis. This finding suggests a dysfunction of inner macular layers which may result from direct retinal involvement or retrograde degeneration.

The aim of this study was to investigate the role of several specific neurocognitive functions in developmental dyslexia (DD). The performances of 60 dyslexic children and 65 age-matched normally reading children were compared on tests of phonological abilities, visual processing, selective and sustained attention, implicit learning, and executive functions. Results documented deficits in dyslexics on both phonological and non-phonological tasks. More stringently, in dyslexic children individual differences in non-phonological abilities accounted for 23.3% of unique variance in word reading and for 19.3% in non-word reading after controlling for age, IQ and phonological skills. These findings are in accordance with the hypothesis that DD is a multifactorial deficit and suggest that neurocognitive developmental dysfunctions in DD may not be limited to the linguistic brain area, but may involve a more multifocal cortical system.

none 5 si PURPOSE: The connective tissue elements forming the check ligaments and portals of the human eye muscles have recently been ascribed with a pulley function. Active positioning of the pulleys over orbital layer contraction during eye movements has been suggested. Other studies have instead demonstrated fibrous tissue connections between all parts of the muscle and the pulleys. We aimed to compare the isometric force developed at the muscle tendon and at the pulleys of the horizontal eye muscles, and to investigate which eye muscle structures might exert force on the pulleys. METHODS: Isometric force development was recorded from the lateral and medial rectus muscles in six patients operated for strabismus under topical anaesthesia. Two strain gauge probes were used, each attached with 5-0 silk sutures either to the muscle tendon or to the pulley. The eye muscles were activated by horizontal saccadic eye movements in steps from 30 degrees in the off-direction to 30 degrees in the on-direction of the muscles. RESULTS: The forces developed at the tendon and pulley were almost identical with respect to amplitude and other parameters. No differences were found in forces developed at the pulleys of the medial and lateral rectus muscles. CONCLUSIONS: The results support the presence of fibrous tissue connections between all eye muscle fibres and pulley structures, rather than orbital fibre control of the pulley. open Lennerstrand, G.; Bolzani, R.; Benassi, M.; Tian, S.; Schiavi, C. Lennerstrand, G.; Bolzani, R.; Benassi, M.; Tian, S.; Schiavi, C.