Italian midwives in Europe: a qualitative study on the experiences of professional migration.

Aim: To explore the reasons for Italian midwives' decision to migrate, and their lived professional and emotional experiences. Methods: A descriptive phenomenological study was conducted recruiting Italian midwives who were working abroad in European countries. We offered a telephone or web interview. Two researchers conducted, audio-recorded, and fully transcribed the interviews and other two researchers, independently, performed a content analysis. Results: Thirty-two midwives having professional experiences in the UK, Ireland, Germany, Switzerland, and Spain were interviewed. Five themes emerged: 1) Education, 2) Migration decision-making, 3) Professional experience abroad, 4) Midwives' perceptions of their role, 5) Satisfaction versus desire to return. Our findings show a general dissatisfaction with Italian job opportunities in terms both of access to employment and work conditions. This scenario is complicated by the status of the professional midwifery in Italy. Conclusion: Stakeholders should ensure that the migration of Italian midwives is not synonymous with dispersion but is a channel of professional growth and mutual exchange.

Motor-like neural dynamics in two parietal areas during arm reaching.

The classical view on motor control makes a clear distinction between the role of motor cortex in controlling muscles and parietal cortex in processing movement plans and goals. However, the strong parieto-frontal connections argue against such clear-cut separation of function. Modern dynamical approaches revealed that population activity in motor cortex can be captured by a limited number of patterns, called neural states that are preserved across diverse motor behaviors. Whether such dynamics are also present in parietal cortex is unclear. Here, we studied neural dynamics in the primate parietal cortex during arm movements and found three main states temporally coupled to the planning, execution and target holding epochs. Strikingly, as reported recently in motor cortex, execution was subdivided into distinct, arm acceleration- and deceleration-related, states. These results suggest that dynamics across parieto-frontal areas are highly consistent and hint that parietal population activity largely reflects timing constraints while motor actions unfold.

Evaluation of effectiveness of photobiostimulation in alleviating side effects after dental implant surgery. A randomized clinical trial

BACKGROUND: To assess if photobiostimulation (PBS) alleviates pain intensity/duration and swelling after implant surgery. MATERIAL AND METHODS: Sixty subjects (27 male and 33 female, with a mean age of 47,13 8.05 years) were included and randomly assigned to experimental group (implant surgery and photobiostimulation), placebo group (implant surgery and simulated photobiostimulation) and control group (implant surgery only). INCLUSION CRITERIA: subjects older than 20 years, with a healthy oral mucosa and requiring implant surgery. EXCLUSION CRITERIA: pregnancy, history of implant failure, light sensitivity, metabolic deseases, consumption of antibiotics or corticosteroids in the last two weeks, smokers and alcohol drinkers. Patients reported the pain experienced by using a numeric rating scale (NRS) at 2 hours, 6 hours, 12 hours, 24 hours and from day 2 to 7. Swelling score was assessed by linear measurements and type and number of analgesic drugs within each time-point were recorded on a spreadsheet. Data of pain and amount of swelling were compared among the three groups by using the Kruskal-Wallis H Test and post-hoc comparisons tests. RESULTS: Pain in the experimental group was less compared to controls and placebo group, at each time intervals (p < 0.001) as well as the maximum pain score (experimental group: median = 2, interquartile range 2-3; control group: median = 8, interquartile range 3,75-9; placebo group: median = 8, interquartile range 6,25-9). Swelling was almost insignificant in the experimental group (maximum value = 1, interquartile range 0-2,75, at 24 hours) compared with control (maximum value = 6, interquartile range 5-8,75, at 24 hours) and placebo (maximum value = 6, interquartile range 5-8, at 24 hours). Subjects in the experimental group assumed less analgesics compared to both controls and placebo groups. CONCLUSIONS: Photobiostimulation is an effective method to reduce pain intensity/duration and swelling after implant surgery

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Use of intralesional cidofovir in the recurrent respiratory papillomatosis: a review of the literature.

OBJECTIVE: Recurrent respiratory papillomatosis (RRP) is characterized by exophytic, benign, and papillary lesions infected by the virus in the epithelium of the upper aerodigestive tract. RRP is caused by persistent infection of the respiratory epithelium by human papillomavirus (HPV) HPV6 and-11. The clinical course of RRP is unpredictable, frequently relapsing, and may be lifelong. The aim of this study is to evaluate the efficacy and safety of the use of intralesional Cidofovir in the treatment of RRP. PATIENTS AND METHODS: We have selected articles on the use of cidofovir as adjuvant therapy in laryngeal papillomatosis. We reviewed 20 reports that enrolled 185 patients with "adult onset recurrent respiratory papillomatosis" (AORRP) and 85 patients with "juvenile onset recurrent respiratory papillomatosis" (JORRP). We evaluated concentration of cidofovir, number of injections, injection interval, therapeutic response, side effects, and progression to dysplasia. RESULTS: The mean concentration of cidofovir was 7.5 mg/ml at injection. The mean number of injections per patient is 6 with 26 days between injections. The percentage of patients with dysplasia after use of cidofovir is 1.48%. The AORRP response to cidofovir is better with a 74% complete response rate, compared to 56.5% of the JORRP. CONCLUSIONS: Intralesion use of cidofovir has a good adjuvant action in RRP increasing the complete remission of the disease. The treatment does not increase the risk of laryngeal dysplasia.

Evaluation of effectiveness of photobiostimulation in alleviating side effects after dental implant surgery. A randomized clinical trial.

BACKGROUND: To assess if photobiostimulation (PBS) alleviates pain intensity/duration and swelling after implant surgery. MATERIAL AND METHODS: Sixty subjects (27 male and 33 female, with a mean age of 47,13 8.05 years) were included and randomly assigned to experimental group (implant surgery and photobiostimulation), placebo group (implant surgery and simulated photobiostimulation) and control group (implant surgery only). INCLUSION CRITERIA: subjects older than 20 years, with a healthy oral mucosa and requiring implant surgery. EXCLUSION CRITERIA: pregnancy, history of implant failure, light sensitivity, metabolic deseases, consumption of antibiotics or corticosteroids in the last two weeks, smokers and alcohol drinkers. Patients reported the pain experienced by using a numeric rating scale (NRS) at 2 hours, 6 hours, 12 hours, 24 hours and from day 2 to 7. Swelling score was assessed by linear measurements and type and number of analgesic drugs within each time-point were recorded on a spreadsheet. Data of pain and amount of swelling were compared among the three groups by using the Kruskal-Wallis H Test and post-hoc comparisons tests. RESULTS: Pain in the experimental group was less compared to controls and placebo group, at each time intervals (p < 0.001) as well as the maximum pain score (experimental group: median = 2, interquartile range 2-3; control group: median = 8, interquartile range 3,75-9; placebo group: median = 8, interquartile range 6,25-9). Swelling was almost insignificant in the experimental group (maximum value = 1, interquartile range 0-2,75, at 24 hours) compared with control (maximum value = 6, interquartile range 5-8,75, at 24 hours) and placebo (maximum value = 6, interquartile range 5-8, at 24 hours). Subjects in the experimental group assumed less analgesics compared to both controls and placebo groups. CONCLUSIONS: Photobiostimulation is an effective method to reduce pain intensity/duration and swelling after implant surgery.

Association between marfan syndrome and oral health status: A systematic review and meta-analysis

Background: The purpose was to identify and assess the existing scientific evidence from epidemiologic, non-experimental, observational studies of associations between Marfan's syndrome and oral diseases. Material and Methods: Electronic literature searches in MEDLINE (OVID), The Cochrane Library, Scopus and the Web of Science were conducted to identify all relevant articles. Eligibility was based on inclusion criteria, and quality assessments were conducted. The outcome variables were probing depth, gingival margin, clinical attachment level, bleeding on probing, gingival status, periodontal status, tooth mobility, furcation involvement and decayed, missing and filled teeth index. After extracting data, meta-analyses were carried out. Results: Out of 527 potentially eligible papers, 3 cross-sectional studies were included. No statistically significant differences were found in the number of sites with bleeding on probing (OR: 1.26; 95% CI: 0.47 to 3.42; P = 0.65; I2: 0%), probing depth (MD: -0.14 mm; 95% CI: -0.24 to 0.53; P = 0.46; I2: 93%), periodontal status (WMD: 0.68 points; 95% CI: -0.48 to 1.83; P = 0.25; I2: 98%) nor number of decayed, missing and filled teeth index score (MD: 1.08 points.; 95% CI: -1.27 to 3.42; P = 0.37; I2: 0%). Conclusions: Patients diagnosed with Marfan's syndrome do not seem to have worsened oral health status. Due to the high number of patients with Marfan's syndrome that have prosthetic heart valves, an adequate dental monitoring as well as a strict maintenance therapy program should be implemented

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Association between Marfan syndrome and oral health status: A systematic review and meta-analysis.

BACKGROUND: The purpose was to identify and assess the existing scientific evidence from epidemiologic, non-experimental, observational studies of associations between Marfan's syndrome and oral diseases. MATERIAL AND METHODS: Electronic literature searches in MEDLINE (OVID), The Cochrane Library, Scopus and the Web of Science were conducted to identify all relevant articles. Eligibility was based on inclusion criteria, and quality assessments were conducted. The outcome variables were probing depth, gingival margin, clinical attachment level, bleeding on probing, gingival status, periodontal status, tooth mobility, furcation involvement and decayed, missing and filled teeth index. After extracting data, meta-analyses were carried out. RESULTS: Out of 527 potentially eligible papers, 3 cross-sectional studies were included. No statistically significant differences were found in the number of sites with bleeding on probing (OR: 1.26; 95% CI: 0.47 to 3.42; P = 0.65; I2: 0%), probing depth (MD: -0.14 mm; 95% CI: -0.24 to 0.53; P = 0.46; I2: 93%), periodontal status (WMD: 0.68 points; 95% CI: -0.48 to 1.83; P = 0.25; I2: 98%) nor number of decayed, missing and filled teeth index score (MD: 1.08 points.; 95% CI: -1.27 to 3.42; P = 0.37; I2: 0%). CONCLUSIONS: Patients diagnosed with Marfan's syndrome do not seem to have worsened oral health status. Due to the high number of patients with Marfan's syndrome that have prosthetic heart valves, an adequate dental monitoring as well as a strict maintenance therapy program should be implemented.

Reduced neural representation of arm/hand actions in the medial posterior parietal cortex.

Several investigations at a single-cell level demonstrated that the medial posterior parietal area V6A is involved in encoding reaching and grasping actions in different visual conditions. Here, we looked for a "low-dimensional" representation of these encoding processes by studying macaque V6A neurons tested in three different tasks with a dimensionality reduction technique, the demixed principal component analysis (dPCA), which is very suitable for neuroprosthetics readout. We compared neural activity in reaching and grasping tasks by highlighting the portions of population variance involved in the encoding of visual information, target position, wrist orientation and grip type. The weight of visual information and task parameters in the encoding process was dependent on the task. We found that the distribution of variance captured by visual information in the three tasks did not differ significantly among the tasks, whereas the variance captured by target position and grip type parameters were significantly higher with respect to that captured by wrist orientation regardless of the number of conditions considered in each task. These results suggest a different use of relevant information according to the type of planned and executed action. This study shows a simplified picture of encoding that describes how V6A processes relevant information for action planning and execution.

Mandibular advancement devices vs nasal-continuous positive airway pressure in the treatment of obstructive sleep apnoea. Systematic review and meta-analysis.

BACKGROUND: Obstructive sleep apnoea (OSA) is a common disorder that may affect at least 2 to 4% of the adult population. Nasal-Continuous Positive Airway Pressure (N-CPAP) is today considered the gold standard for the treatment of OSA. The development of oral appliances (OAs) represents a new approach for the management of this pathology. The aim of this systematic review is to compare the efficacy of OAs and N-CPAP in the treatment of patients with mild to severe OSA. MATERIAL AND METHODS: A PubMed-MEDLINE and Cochrane databases search of articles published between 1982 and 2016 comparing the effect of N-CPAP and OAs in OSA patients was conducted during July 2016. The studies were selected and stratified according to PRISMA and SORT criteria. The main outcome measure was post-treatment Apnoea-Hypopnoea Index (AHI) while secondary outcomes included post-treatment Epworth Score Scale (ESS) score and lowest Oxygen Saturation level. RESULTS: N-CPAP was significantly more effective in suppressing AHI than OA. Moreover, N- CPAP was significantly more effective in increasing post-treatment lowest Oxygen Saturation level than OA. However, no significant different in decreasing ESS values was found between the two treatments. CONCLUSIONS: On the basis of evidence in this review it would appear appropriate to offer OA therapy to those who are unwilling or unable to persist with CPAP therapy. N-CPAP still must be considered the gold standard treatment for OSA and, therefore, OAs may be included in the list of alternative options.

Transoral robotic surgery (TORS): a new tool for high risk tracheostomy decannulation.

Tracheostomy decannulation has always been considered a procedure with an attendant risk, especially in patients with a reduced upper airway diameter as is commonly observed in the obstructive sleep apnoea (OSA) population. We report on 4 cases where transoral robotic surgery (TORS) helped in the management of long-term cannulated patients. The aims of our paper are: 1. To demonstrate how the otolaryngology team can help identify patients at high risk for decannulation failure; and 2. To demonstrate how TORS may aid in the decannulation process of patients at high risk for failure due to severe tongue base hypertrophy. From our experience, TORS appears to offer an effective option to aid in the decannulation of patients with a severe hypertrophy of the base of tongue and floppy epiglottis.

Hipofosfatemia y su relación con el inicio del soporte nutricional en pacientes críticos / Hypophosphatemia and its relationship with the start of nutritional support in critical patients

Objetivos: Establecer la relación entre el inicio del soporte nutricional y el desarrollo de hipofosfatemia. Determinar la incidencia de hipofosfatemia, evaluar el desarrollo de hipofosfatemia en pacientes clasificados "en riesgo" de desarrollar síndrome de realimentación según la guía NICE, relacionar hipofosfatemia y gravedad de la enfermedad mediante el puntaje APACHE II. Materiales y Métodos: Estudio analítico, observacional y retrospectivo, que evaluó la determinación plasmática seriada antes del inicio del soporte nutricional y al primer día de este, en 61 enfermos críticos. Los pacientes fueron clasificados como "con riesgo" o "sin riesgo" de desarrollar síndrome de realimentación según la guía NICE y se calculó el puntaje APACHE II. El análisis se llevó a cabo con las prueba t de Student y correlación lineal para datos cuantitativos, y ji al cuadrado para datos cualitativos. Se consideraron estadísticamente significativos valores p<0,05. Resultados: El nivel de fosfato del día 0 sin alimentación al día 1 del soporte nutricional disminuyó significativamente (p = 0,001). La incidencia de hipofosfatemia al día 1 fue del 6% y la de hipofosfatemia grave, 2,6%. La clasificación mediante la guía NICE no produjo diferencia significativa en el valor de fosfato (p = 0,103). No se halló asociación entre hipofosfatemia y puntaje APACHE II (p = 0,73). Conclusiones: La disminución del nivel de fosfato en pacientes críticos al comienzo del soporte nutricional manifiesta la relación de este ion con el inicio de la alimentación. La hipofosfatemia no fue condicionada por la clasificación "en riesgo" según la guía NICE o la gravedad de la enfermedad por APACHE II. Estos hallazgos confirman la importancia del monitoreo periódico de los valores de fosfato y de aquellos factores de riesgos que puedan conducir a su disminución(AU)

Objectives: Establish the relationship between onset of nutritional support and development of hypophosphatemia.To determine the incidence of hypophosphatemia and assess development of hypophosphatemia in patients classified as "at risk" of refeeding syndrome according to NICE guide. To relate hypophosphatemia and severity of the disease through APACHE II score. Materiales and Methods: Analytical, observational and retrospective study to evaluate the serial laboratory results before nutritional support and the first day of it in 61 critically ill patients. Patients were classified as "at risk" or "not at risk" of developing refeeding syndrome according to NICE guide and APACHE II score. Analysis of quantitative data was performed using Student t test and linear correlation; chi-squared test was used for qualitative data. A value of p<0.05 was considered statistically significant. Results: Phosphate level without food on day 0 to day 1 of nutritional support decreased significantly (p=0.001). The incidence of hypophosphatemia to day 1 was 6% and that of severe hypophosphatemia was 2.6%. NICE guide classification produced no significant difference in the level of phosphate (p=0.103). No association between hypophosphatemia and APACHE II score (p=0.73) was found. Conclusiones: The decreased level of phosphate found at the start of nutritional support in critically ill patients shows the relationship of this ion with the start of feeding. Hypophosphatemia was not conditioned by "at risk" classification according to the NICE guide or the severity of the disease according to APACHE II score. These findings confirm the importance of regular monitoring of phosphate and those risk factors that could lead to its decline(AU)

Reference frames for reaching when decoupling eye and target position in depth and direction.

Spatial representations in cortical areas involved in reaching movements were traditionally studied in a frontoparallel plane where the two-dimensional target location and the movement direction were the only variables to consider in neural computations. No studies so far have characterized the reference frames for reaching considering both depth and directional signals. Here we recorded from single neurons of the medial posterior parietal area V6A during a reaching task where fixation point and reaching targets were decoupled in direction and depth. We found a prevalent mixed encoding of target position, with eye-centered and spatiotopic representations differently balanced in the same neuron. Depth was stronger in defining the reference frame of eye-centered cells, while direction was stronger in defining that of spatiotopic cells. The predominant presence of various typologies of mixed encoding suggests that depth and direction signals are processed on the basis of flexible coordinate systems to ensure optimal motor response.

Multiple representation of reaching space in the medial posterior parietal area V6A.

During foveal reaching, the activity of neurons in the macaque medial posterior parietal area V6A is modulated by both gaze and arm direction. In the present work, we dissociated the position of gaze and reaching targets, and studied the neural activity of single V6A cells while the eyes and reaching targets were arranged in different spatial configurations (peripheral and foveal combinations). Target position influenced neural activity in all stages of the task, from visual presentation of target and movement planning, through reach execution and holding time. The majority of neurons preferred reaches directed toward peripheral targets, rather than foveal. Most neurons discharged in both premovement and action epochs. In most cases, reaching activity was tuned coherently across action planning and execution. When reaches were planned and executed in different eye/target configurations, multiple analyses revealed that few neurons coded reaching actions according to the absolute position of target, or to the position of target relative to the eye. The majority of cells responded to a combination of both these factors. These data suggest that V6A contains multiple representations of spatial information for reaching, consistent with a role of this area in forming cross-reference frame representations to be used by premotor cortex.

Common neural substrate for processing depth and direction signals for reaching in the monkey medial posterior parietal cortex.

Many psychophysical studies suggest that target depth and direction during reaches are processed independently, but the neurophysiological support to this view is so far limited. Here, we investigated the representation of reach depth and direction by single neurons in area V6A of the medial posterior parietal cortex (PPC) of macaques, while a fixation-to-reach task in 3-dimensional (3D) space was performed. We found that, in a substantial percentage of V6A neurons, depth and direction signals jointly influenced fixation, planning, and arm movement-related activity. While target depth and direction were equally encoded during fixation, depth tuning became stronger during arm movement planning, execution, and target holding. The spatial tuning of fixation activity was often maintained across epochs, and depth tuning persisted more than directional tuning across epochs. These findings support for the first time the existence of a common neural substrate for the encoding of target depth and direction during reaches in the PPC. Present results also highlight the presence of several types of V6A cells that process independently or jointly signals about eye position and arm movement planning and execution in order to control reaches in 3D space. A conceptual framework for the processing of depth and direction for reaching is proposed.

Body-centered, mixed, but not hand-centered coding of visual targets in the medial posterior parietal cortex during reaches in 3D space.

The frames of reference used by neurons in posterior parietal cortex (PPC) to encode spatial locations during arm reaching movements is a debated topic in modern neurophysiology. Traditionally, target location, encoded in retinocentric reference frame (RF) in caudal PPC, was assumed to be serially transformed to body-centered and then hand-centered coordinates rostrally. However, recent studies suggest that these transformations occur within a single area. The caudal PPC area V6A has been shown to represent reach targets in eye-centered, body-centered, and a combination of both RFs, but the presence of hand-centered coding has not been yet investigated. To examine this issue, 141 single neurons were recorded from V6A in 2 Macaca fascicularis monkeys while they performed a foveated reaching task in darkness. The targets were presented at different distances and lateralities from the body and were reached from initial hand positions located at different depths. Most V6A cells used body-centered, or mixed body- and hand-centered coordinates. Only a few neurons used pure hand-centered coordinates, thus clearly distinguishing V6A from nearby PPC regions. Our findings support the view of a gradual RF transformation in PPC and also highlight the impact of mixed frames of reference.

The human homologue of macaque area V6A.

In macaque monkeys, V6A is a visuomotor area located in the anterior bank of the POs, dorsal and anterior to retinotopically-organized extrastriate area V6 (Galletti et al., 1996). Unlike V6, V6A represents both contra- and ipsilateral visual fields and is broadly retinotopically organized (Galletti et al., 1999b). The contralateral lower visual field is over-represented in V6A. The central 20°-30° of the visual field is mainly represented dorsally (V6Ad) and the periphery ventrally (V6Av), at the border with V6. Both sectors of area V6A contain arm movement-related cells, active during spatially-directed reaching movements (Gamberini et al., 2011). In humans, we previously mapped the retinotopic organization of area V6 (Pitzalis et al., 2006). Here, using phase-encoded fMRI, cortical surface-based analysis and wide-field retinotopic mapping, we define a new cortical region that borders V6 anteriorly and shows a clear over-representation of the contralateral lower visual field and the periphery. As with macaque V6A, the eccentricity increases moving ventrally within the area. The new region contains a non-mirror-image representation of the visual field. Functional mapping reveals that, as in macaque V6A, the new region, but not the nearby area V6, responds during finger pointing and reaching movements. Based on similarity in position, retinotopic properties, functional organization and relationship with the neighboring extrastriate visual areas, we propose that the new cortical region is the human homologue of macaque area V6A.

Human v6: the medial motion area.

Cortical-surface-based functional Magnetic Resonance Imaging mapping techniques and wide-field retinotopic stimulation were used to verify the presence of pattern motion sensitivity in human area V6. Area V6 is highly selective for coherently moving fields of dots, both at individual and group levels and even with a visual stimulus of standard size. This stimulus is a functional localizer for V6. The wide retinotopic stimuli used here also revealed a retinotopic map in the middle temporal cortex (area MT/V5) surrounded by several polar-angle maps that resemble the mosaic of small areas found around macaque MT/V5. Our results suggest that the MT complex (MT+) may be specialized for the analysis of motion signals, whereas area V6 may be more involved in distinguishing object and self-motion.

Real-time supervisor system based on trinary logic to control experiments with behaving animals and humans.

A new method is presented based on trinary logic able to check the state of different control variables and synchronously record the physiological and behavioral data of behaving animals and humans. The basic information structure of the method is a time interval of defined maximum duration, called time slice, during which the supervisor system periodically checks the status of a specific subset of input channels. An experimental condition is a sequence of time slices subsequently executed according to the final status of the previous time slice. The proposed method implements in its data structure the possibility to branch like an if-else cascade and the possibility to repeat parts of it recursively like the while-loop. Therefore its data structure contains the most basic control structures of programming languages. The method was implemented using a real-time version of LabVIEW programming environment to program and control our experimental setup. Using this supervision system, we synchronously record four analog data channels at 500 Hz (including eye movements) and the time stamps of up to six neurons at 100 kHz. The system reacts with a resolution within 1 ms to changes of state of digital input channels. The system is set to react to changes in eye position with a resolution within 4 ms. The time slices, experimental conditions, and data are handled by relational databases. This facilitates the construction of new experimental conditions and data analysis. The proposed implementation allows continuous recording without an inter-trial gap for data storage or task management. The implementation can be used to drive electrophysiological experiments of behaving animals and psychophysical studies with human subjects.

Early- and late-responding cells to saccadic eye movements in the cortical area V6A of macaque monkey.

The cortical area V6A, located in the dorsal part of the anterior bank of the parieto-occipital sulcus, contains retino- and craniocentric visual neurones together with neurones sensitive to gaze direction and/or saccadic eye movements, somatosensory stimulation and arm movements. The aim of this work was to study the dynamic characteristics of V6A saccade-related activity. Extracellular recordings were carried out in six macaque monkeys performing a visually guided saccade task with the head restrained. The task was performed in the dark, in both the dark and light, and sometimes in the light only. The discharge of certain neurones during saccades is due to their responsiveness to visual stimuli. We used a statistical method to distinguish responses due to visual stimulation from those responsible for saccadic control. Out of 597 V6A neurones tested, 66 (11%) showed responses correlated with saccades; 26 of 66 responded also to visual stimulation and 31 of 66 did not; the remaining 9 were not visually tested. We calculated the response latency to saccade onset and its inter-trial variance in 24 of 66 neurones. Saccade neurones could respond before, during or after the saccade. Neurones responding before saccade-onset or during saccades had much higher latency variance than neurones responding after saccades. The early-responding cells had a mean latency (+/-SD) of -64+/-62 ms, while the late-responding cells a mean latency of +89+/-20 ms. The responses to saccadic eye movements were directionally sensitive and varied with the amplitude of the saccade. Responses of late-responding cells disappeared in complete darkness. We suggest that the activity of early-responding cells represents the intended saccadic eye movement or the shift of attention towards another part of the visual space, whereas that of late-responding cells is a visual response due to retinal stimulation during saccades.

'Arm-reaching' neurons in the parietal area V6A of the macaque monkey.

In previous experiments we have found that several cells of area V6A in the macaque superior parietal lobule were activated by small and stereotyped movements of the arms (C. Galletti, P. Fattori, D. F. Kutz & P. P. Battaglini, Eur. J. Neurosci., 1997, 9, 410). This behaviour was not accounted for by retinal information, nor by somatosensory inputs from the arms. We now want to investigate whether V6A neurons are modulated by purposeful movements aimed at reaching visual targets or targets located outside the field of view. V6A neuronal activity was collected while monkeys performed arm movements during an instructed-delay reaching task in darkness. The task required the animal to reach out for a visual target in the peripersonal space and to bring the hand back to its body. Quantitative analysis of neuronal activity carried out on 55 V6A neurons showed that: (i) the great majority of neurons (71%) was significantly modulated during the execution of arm movements; (ii) 30% of neurons were significantly modulated during preparation of reaching; and (iii) modulations during both execution and preparation of reaching occurred in the absence of any visual feedback and were not due to eye movements. V6A reach-related neurons could be useful in guiding the hand to reach its target with or without visual feedback.