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Abstract.Heart rate variability (HRV) has been linked to effective functioning of prefrontal-subcortical inhibitory circuits. Despite the recognized role of the prefrontal cortex (PFC) in executive functions linked to inhibitory capacity, studies linking HRV to executive functions are inconsistent, likely due to potential confounders. The present study sought to examine this relation in a sample of 50 healthy participants (31 females; Mage= 24.2 years) who underwent assessment of resting HRV and two executive tasks assessing inhibitory control, namely the Rule Shift Cards and the Hayling Sentence Completion Test. Hierarchical multiple regressions showed that HRV predicted performance on both tasks (i.e., time taken to inhibit a strongly activated response) above and beyond the role of sex, body mass index, and impulsivity. Present results disconfirm that the HRV-executive function association is only due to confounders, and corroborate such relationship with the use of two ecological tasks assessing inhibitory control. Current findings support the Neurovisceral Integration Model and provide plausible explanation for previous inconsistent results.

The golden ratio (GR) is an irrational number (close to 1.618) that repeatedly occurs in nature as well as in masterpieces of art. The GR has been considered a proportion perfectly representing beauty since ancient times, and it was investigated in several scientific fields, but with conflicting results. This study aims at investigating if this proportion is associated with a judgment of beauty independently of the type of the stimulus, and the factors that may affect this aesthetic preference. In Experiment 1, an online psychophysical questionnaire was administered to 256 volunteers asked to choose among three possible proportions between the parts of the same stimulus (GR, 1.5, and 1.8). In Experiment 2, we recorded eye movements in 15 participants who had to express an aesthetic judgment on the same stimuli of Experiment 1. The results revealed a slight overall preference for GR (53%, p< .001), with higher preferences for stimuli representing humans, anthropomorphic sculptures, and paintings, regardless of the cultural level. In Experiment 2, a shorter dwell time was significantly associated with a better aesthetic judgment (p= .005), suggesting the possibility that GR could be associated with easier visual processing, and it could be hence considered as a visual affordance.

It has recently been discovered that during a virtual reality task of painting, if the subjects have the illusion of recreating an artistic masterpiece, they improve their performances and perceive less fatigue compared to simply coloring a virtual canvas. This phenomenon has been called the Michelangelo effect. However, it was unclear if this effect was related to the aesthetic experience of beauty or if it was specific to artistic stimuli. To clarify this point, 26 healthy subjects performed the virtual task of erasing a blank sheet on the canvas, revealing an image that could be a painting or a photo, classified as beautiful or not. Beautiful paintings were famous artistic portraits, non‐beautiful paintings were rough reproductions of them. Photos of popular people were matched with paintings according to their similarity for somatic traits, posture, and clothes. Beautiful and non‐beautiful photos were classified according to whether the pictured person was famous or not for their beauty. For each stimulus the objective beauty, subjective beauty, and effort to complete the task perceived by the subject were self‐assessed on a numerical rating scale, recorded and analyzed. Furthermore, the hand kinematic trajectory was instrumentally recorded and its spatiotemporal parameters were computed. Less fatigue was perceived for the paintings than for the photos (p =.020), but not for beautiful versus non‐beautiful stimuli (p =.325). Only in the artistic stimuli, subjective beauty was found to be negatively correlated with perceived fatigue (p =.030) and performed errors (p =.005). The kinematic parameters were found to be affected by the interactions between the gender of the participant and that of the person in the photo. These results supported the idea that the Michelangelo effect was stronger when subjects interacted with artefacts, modulated by the perceived beauty of the artistic stimulus.

Even when focused on an effortful task we retain the ability to detect salient environmental information, and even irrelevant visual stimuli can be automatically detected. However, to which extent unattended information affects attentional control is not fully understood. Here we provide evidences of how the brain spontaneously organizes its cognitive resources by shifting attention between a selective-attending and a stimulus-driven modality within a single task. Using a spatial cueing paradigm we investigated the effect of cue-target asynchronies as a function of their probabilities of occurrence (i.e., relative frequency). Results show that this accessory information modulates attentional shifts. A valid spatial cue improved participants’ performance as compared to an invalid one only in trials in which target onset was highly predictable because of its more robust occurrence. Conversely, cuing proved ineffective when spatial cue and target were associated according to a less frequent asynchrony. These patterns of response depended on asynchronies’ probability and not on their duration.

The aim of this study was to investigate whether it is possible to strengthen the rehabilitation of spatial hemineglect by combining standard training for spatial scanning with optokinetic stimulation. A simple randomized design was used: one group of neglect patients was treated with a combination of the two techniques, and a second group received only the standard treatment. Both treatments were given for six consecutive weeks and produced significant improvements. However, addition of the optokinetic stimulation did not improve the patients' performance. Also, none of the independent variables (i.e., presence/absence of hemianopia) predicted the positive effect occasionally observed in individual patients.

The aim of this study was to assess the specific influence of poststroke depression (PSD) on both basal functional status and rehabilitation results. We performed a case-control study in 290 stroke inpatients, matched for age (±1 year) and onset admission interval (±3 days) and divided in two groups according to the presence (PSD+) or absence (PSD–) of PSD. All PSD+ patients were treated with antidepressants (AD), mainly with fluoxetine. PSD+ patients, despite similar severity of stroke, showed greater disability in coping with activities of daily living (ADL) on admission and greater disability both in ADL and mobility at discharge than PSD– patients. Although both groups exhibited similar average functional improvement during rehabilitation, PSD– patients were nearly twice as likely to show excellent recovery both on ADL and mobility as PSD+ patients (OR = 1.95, 95% CI = 1.01–3.75 and OR = 2.23, 95% CI = 1.14–4.35, respectively). All AD drugs improved depressive symptoms. Few relevant side effects were observed: fluoxetine was discontinued in 2 patients because of insomnia and in 2 patients because of nausea; paroxetine was stopped in 1 patient because of nausea and dry mouth. Our results confirm the unfavorable influence of PSD on functional outcome, despite pharmacological treatment.

Paolucci S, Grasso MG, Antonucci G, Bragoni M, Troisi E, Morelli D, Coiro P, De Angelis D, Rizzi F. Mobility status after inpatient stroke rehabilitation: 1-year follow-up and prognostic factors. Arch Phys Med Rehabil 2001;82:2-8. Objectives:To evaluate the stability of mobility status achieved by stroke patients during hospital rehabilitation treatment over time and to identify reliable prognostic factors associated with mobility changes. Design:Follow-up evaluation in consecutive first-ever stroke patients 1 year after hospital discharge. Multiple logistic regressions were used to analyze increases and decreases in Rivermead Mobility Index (RMI) scores (dependent variables) between discharge and follow-up. Independent variables were medical, demographic, and social factors. Setting:Rehabilitation hospital. Patients:A cohort of 155 patients with sequelae of first stroke, with a final sample of 141. Main Outcome Measures:Mobility status at 1-year follow-up, as measured by the RMI, and odds ratios (OR) for improvement and decline in mobility. Results:Functionally, 19.9% improved the mobility levels achieved during the inpatient rehabilitation treatment; levels of 42.6% worsened. Patients with global aphasia (OR = 5.66; 95% confidence interval [CI], 1.50-21.33), unilateral neglect (OR = 3.01; 95% CI, 1.21-7.50), and age 75 years or older (OR = 5.77; 95% CI, 1.42-23.34) had a higher probability of mobility decline than the remaining patients. Postdischarge rehabilitation treatment (PDT), received by 52.5% of the final sample, was significantly and positively associated with mobility improvement (OR = 5.86; 95% CI, 2.02-17.00). Absence of PDT was associated with a decline in mobility (OR = 3.73; 95% CI, 1.73-8.04). Conclusions:In most cases, mobility status had not yet stabilized at hospital discharge. PDT was useful in preventing a deterioration in mobility improvement achieved during inpatient treatment and in helping increase the likelihood of further mobility improvement. © 2001 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

This study was designed to evaluate functional status at a 1-year follow-up in consecutive first-stroke patients after discharge from rehabilitation hospital and to identify reliable prognostic factors associated with changes in their abilities. Functional evaluation was made of consecutive patients 1 year after discharge to their own homes. Two multiple logistic regressions (forward stepwise) were performed using both improvement and worsening of the Barthel Index score between discharge and follow-up as dependent variables. Independent variables were medical, demographic and social factors. The final sample included 157 out of 172 patients. During the follow-up, 10 patients (5.81%) died because of a new cerebrovascular event, 1 patient died of myocardial infarction, 2 patients had new strokes and 2 fractured their paretic legs. Functionally, 43.3% of the patients maintained the level they achieved during inpatient rehabilitation treatment, 23.6% improved and the remaining 33.1% worsened. Patients with hemineglect and aged ≥65 years had a higher probability of functional worsening (odds ratio, OR = 3.77, 95% confidence interval, CI = 1.42– 10.0 and OR = 3.93, 95% CI = 1.72–8.95, respectively). Postdischarge rehabilitation (performed for 46.5% of the final sample) was significantly and positively associated with functional improvement (OR = 7.23, 95% CI = 2.89–18.05), and its absence with functional worsening (OR = 12.32, 95% CI = 4.47–37.01). In conclusion, in nearly half of the cases, functional status was still not stabilized at the time of discharge from the rehabilitation hospital. Postdischarge outpatient treatment was useful for preventing worsening of the functional ability achived during inpatient treatment and increased the possibility of further functional improvement. Age ≥65 years and hemineglect were predictors of functional worsening at follow-up.

The effectiveness of neglect rehabilitation training has been studied in two randomly selected groups of right brain-damaged patients. All patients proved heminattentive on a standard battery 2 months or more after the CVA. One group received 2 months of treatment immediately after admission to a clinic, and the other group received only general cognitive stimulation for the same amount of time. At the end of this period a comparison showed significant improvement in the first group, based on a standard test battery and a functional scale. The second group was then given rehabilitation training for neglect for the same amount of time and obtained similar improvement. It is concluded that the rehabilitation program produces significant results, which generalize to situations similar to those of everyday life.The importance of the duration of training on the generalization of learning is briefly discussed with reference to previous negative reports in the literature.

The aims of this study were: (1) to identify reliable prognostic factors for detecting subgroups of no, low and high response in consecutive patients admitted for rehabilitation of first stroke sequelae, and (2) to quantify the relative risk of poor or excellent prognosis on both Activities of Daily Living (ADL) and mobility for each significant variable. We prospectively studied 440 of 475 patients. From a group of 32 independent variables, those significantly associated with no, low and high effectiveness on both ADL and mobility were selected by means of multiple regression; then, the relative risk was calculated for each variable that significantly entered the multiple regressions. Patients with severe impairment or with global aphasia showed a relative risk of no response 4–6 times higher than that of other patients. An interval before rehabilitation longer than 2 months was associated with an increasing risk of no response. Elderly patients had a significantly higher relative risk of low response both on ADL and mobility. The presence of hemineglect and depression was associated with an increasing risk of low response on ADL but not on mobility. The absence of hemineglect and a short interval are prerequisites for an excellent functional prognosis on both ADL and mobility. A minor impairment, employed status, the absence of global aphasia and age ≤65 years increased the risk of high response. At the beginning of treatment, clear prognostic factors for the detection of subgroups with poor or excellent rehabilitation prognosis can be identified.

A study of the effect of specific training for visual neglect on the recovery of motor and functional impairment in stroke patients is reported. Two groups of right hemisphere stroke patients with hemispatial neglect and one group without neglect were assessed by means of three functional and neurological scales (Rivermead Mobility Index, Barthel Index, Canadian Neurological Scale). Three evaluations were made at 0, 2 and 4 months from the beginning of physical rehabilitation. During the first 2 months of physical rehabilitation one of the two groups of neglect patients was randomly assigned to specific training for neglect, and the second group to a general cognitive intervention; during the final 2 months of rehabilitation the types of training were switched in the two groups. The non-neglect patients improved steadily during physical rehabilitation. In contrast, the functional recovery of the two neglect groups was time-locked to the period of the specific training for neglect. At the time of admission, the two neglect groups performed at the same level; after 2 months of rehabilitation, the group with neglect training showed higher functional recovery than the group with only general cognitive intervention. When the latter group received neglect training, there was no longer any difference between the two neglect groups. This pattern was present for both of the functional scales used but not for the neurological scale. Motor and functional recovery of stroke patients with neglect seems to be significantly improved by the simultaneous presence of a treatment specifically focused on neglect.

The role of local and global visual mechanisms in individual differences in the rod-and-frame (RF) effect was investigated. Field-dependent and field-independent observers, selected on the basis of Witkin and Asch's (1948) classical procedure, were submitted to the small RF test (Coren & Hoy, 1986). Four frame tilts and two gap sizes were used. As expected, direct effects (i.e., rod settings in the direction of frame tilt) were observed at small degrees of frame tilt, while indirect effects (i.e., rod settings in the direction opposite that of frame tilt) were observed at larger frame tilts. Fielddependent observers showed larger direct effects in the case of the small gap. Indirect effects were comparable in both field-dependent and field-independent subjects, regardless of gap size. Following the model proposed by Wenderoth and Johnstone (1987), these findings indicate that low-level visual mechanisms, responsible for local orientation interactions, have a different gain in fielddependent and field-independent individuals. In contrast, global visual mechanisms, presumably acting [ABSTRACT FROM AUTHOR]

The role of the spatial separation between the ends of a rod and a frame's inner edge (gap) in modulating the rod-and-frame effect (RFE) has been studied here with frames subtending either large or small retinal angles. With a large frame, rod settings were always in the direction of frame tilt (direct effects) and varied inversely with gap size. With a small frame, rod settings were in the direction of frame tilt for tilts between 7.5° and 15°; with larger frame tilts, rod settings in the direction opposite that of the frame were observed (indirect effects). Increasing gap size produced a tendency toward negativity (away from frame tilt). Consequently, direct effects were larger for small gaps, while the opposite was true for indirect effects. Overall, these results point to the importance of gap size in modulating the RFE, for both large and small displays. [ABSTRACT FROM AUTHOR]

When required to set the endpoints of an imaginary horizontal line of a given length on the basis of its midpoint printed on a sheet of paper, left neglect patients most frequently misplaced endpoints leftwards. Though giving rise to the very same disproportion usually found with these patients on canonical line bisection tasks, this behaviour cannot be accommodated by current explanations of unilateral neglect. When the task was executed during leftward optokinetic stimulation (OKS), a manoeuvre known temporarily to improve neglect symptoms, the disproportion increased instead of vanishing. We therefore suggest that unilateral neglect is a manifestation of a disorder primarily implying a horizontal anisometry of space representation and that manipulations such as OKS may remove neglect without normalizing the representational medium itself.