Hedonic and autonomic responses in promoting affective touch.

Interpersonal touch is intrinsically reciprocal since it entails a person promoting and another receiving the touch. While several studies have investigated the beneficial effects of receiving affective touch, the affective experience of caressing another individual remains largely unknown. Here, we investigated the hedonic and autonomic responses (skin conductance and heart rate) in the person promoting affective touch.

Effects of prism adaptation and visual scanning training on perceptual and response bias in unilateral spatial neglect.

In some patients with unilateral spatial neglect, symptoms reflect impaired lateralized spatial attention and representation (perceptual bias) whereas in others the inability to respond to stimuli located in contralesional space (response bias). Here, we investigated whether prismatic adaptation (PA) and visual scanning training (VST) differentially affect perceptual and response bias and whether rehabilitation outcome depends on the type of bias underlying symptoms. Two groups of neglect patients in the subacute phase were evaluated before, immediately after, and two weeks following 10 days of PA ( = 9) or VST ( = 9).

Beyond alpha-band: The neural correlate of creative thinking.

The compound nature of creativity entails the interplay of multiple cognitive processes, making it difficult to attribute creativity to a single neural signature. Divergent thinking paradigms, widely adopted to investigate creative production, have highlighted the key role of specific mental operations subserving creativity, such as inhibition of external stimuli, loose semantic associations, and mental imagery. Neurophysiological studies have typically shown a high alpha rhythm synchronization when individuals are engaged in creative ideation.

Effective connectivity underlying neural and behavioral components of prism adaptation.

Prism adaptation (PA) is a form of visuomotor training that produces both sensorimotor and cognitive aftereffects depending on the direction of the visual displacement. Recently, a neural framework explaining both types of PA-induced aftereffects has been proposed, but direct evidence for it is lacking. We employed Structural Equation Modeling (SEM), a form of effective connectivity analysis, to establish directionality among connected nodes of the brain network thought to subserve PA.

Changing your body changes your eating attitudes: embodiment of a slim virtual avatar induces avoidance of high-calorie food.

The virtual-reality full-body illusion paradigm has been suggested to not only trigger the illusory ownership of the avatar's body but also the attitudinal and behavioral components stereotypically associated to that kind of virtual body. In the present study, we investigated whether this was true for stereotypes related to body size: body satisfaction and eating control behavior. Healthy participants underwent the full-body illusion paradigm with an avatar having either a larger or a slimmer body than their own, and were assessed for implicit attitudes towards body image and food calorie content at baseline and after each full-body illusion session.

Self-other distinction modulates the social softness illusion.

The social softness illusion (i.e., the tendency to perceive another person's skin as softer than our own) is thought to promote the sharing of social-emotional experiences because of the rewarding properties of receiving and giving social affective touch.

Callosal anisotropy predicts attentional network changes after parietal inhibitory stimulation.

Hemispatial neglect is thought to result from disruption of interhemispheric equilibrium. Right hemisphere lesions deactivate the right frontoparietal network and hyperactivate the left via release from interhemispheric inhibition. Support for this putative mechanism comes from neuropsychological evidence as well as transcranial magnetic stimulation (TMS) studies in healthy subjects, in whom right posterior parietal cortex (PPC) inhibition causes neglect-like, rightward, visuospatial bias.

Prism Adaptation Modulates Connectivity of the Intraparietal Sulcus with Multiple Brain Networks.

Prism adaptation (PA) alters spatial cognition according to the direction of visual displacement by temporarily modifying sensorimotor mapping. Right-shifting prisms (right PA) improve neglect of left visual field in patients, possibly by decreasing activity in the left hemisphere and increasing it in the right. Left PA shifts attention rightward in healthy individuals by an opposite mechanism.

Left-shifting prism adaptation boosts reward-based learning.

Visuospatial cognition has an inherent lateralized bias. Individual differences in the direction and magnitude of this bias are associated with asymmetrical D2/3 dopamine binding and dopamine system genotypes. Dopamine level affects feedback-based learning and dopamine signaling asymmetry is related to differential learning from reward and punishment.

Motor cortex inhibition by TMS reduces cognitive non-motor procedural learning when immediate incentives are present.

Inhibitory repetitive transcranial magnetic stimulation (rTMS) of the primary motor area (M1) impairs motor sequence-learning, but not basic motor function. It is unknown if this is specific for motor forms of procedural learning or a more general effect. To investigate, we tested the effect of M1-inhibition on the weather prediction task (WPT), a learning task with minimal motor learning component.

The asymmetrical effect of leftward and rightward prisms on intact visuospatial cognition.

Rightward prismatic adaptation (RPA) can reduce neglect symptoms in patients whereas adaptation to leftward deviating prisms (LPA) can induce neglect-like behavior in healthy subjects. One influential anatomo-functional model of prismatic adaptation (PA) postulates that it inhibits activity of the posterior parietal cortex (PPC) contralateral to the prismatic deviation. By hypo-activating the PPC and thus eventually acting on interhemispheric balance, both LPA and RPA could possibly affect visuospatial perception in healthy subjects, however, such behavioral modulation has seldom been reported after RPA.

Adaptation to Leftward Shifting Prisms Alters Motor Interhemispheric Inhibition.

Adaptation to rightward shifting prisms (rightward prism adaptation, RPA) ameliorates neglect symptoms in patients while adaptation to leftward shifting prisms (leftward prism adaptation, LPA) induces neglect-like behaviors in healthy subjects. It has been hypothesized that prism adaptation (PA) modulates interhemispheric balance between the parietal cortices by inhibiting the posterior parietal cortex (PPC) contralateral to the prismatic deviation, but PA's effects on interhemispheric inhibition (IHI) have not been directly investigated. Since there are hyper-excitable connections between the PPC and primary motor cortex (M1) in the left hemisphere of neglect patients, we reasoned that LPA might mimic right hemisphere lesions by reducing parietal IHI, hyper-exciting the left PPC and PPC-M1 connections, and in turn altering IHI at the motor level.

Paired-Pulse Parietal-Motor Stimulation Differentially Modulates Corticospinal Excitability across Hemispheres When Combined with Prism Adaptation.

Rightward prism adaptation ameliorates neglect symptoms while leftward prism adaptation (LPA) induces neglect-like biases in healthy individuals. Similarly, inhibitory repetitive transcranial magnetic stimulation (rTMS) on the right posterior parietal cortex (PPC) induces neglect-like behavior, whereas on the left PPC it ameliorates neglect symptoms and normalizes hyperexcitability of left hemisphere parietal-motor (PPC-M1) connectivity. Based on this analogy we hypothesized that LPA increases PPC-M1 excitability in the left hemisphere and decreases it in the right one.

Areas of Brain Damage Underlying Increased Reports of Behavioral Disinhibition.

Disinhibition, the inability to inhibit inappropriate behavior, is seen in frontal-temporal degeneration, Alzheimer's disease, and stroke. Behavioral disinhibition leads to social and emotional impairments, including impulsive behavior and disregard for social conventions. The authors investigated the effects of lesions on behavioral disinhibition measured by the Neuropsychiatric Inventory in 177 veterans with traumatic brain injuries.

The left inferior frontal gyrus is crucial for reading the mind in the eyes: brain lesion evidence.

Deficit in the ability to understand and predict the mental states of others is one of the central features of traumatic brain injury (TBI), leading to problems in social-daily life such as social withdrawal and the inability to maintain work or family relationships. Although several functional neuroimaging studies have identified a widely distributed brain network involved in the Reading the Mind in the Eyes Test (RMET), the necessary brain regions engaged in this capacity are still heavily debated. In this study, we combined the RMET with a whole-brain voxel-based lesion symptom mapping (VLSM) approach to identify brain regions necessary for adequate RMET performance in a large sample of patients with penetrating TBI (pTBI).

Object and space perception - is it a matter of hemisphere?

In the 1980s, following Newcombe's observations, Ungerleider and Mishkin put forward the functional subdivision of the visual system into a ventral stream dedicated to object perception and a dorsal stream dedicated to space perception. Ten years after this discovery, the perception-action model re-defined the dorsal stream as responsible for non-conscious visual guidance, and most recently a tripartition has been suggested to account for a variety of visuospatial functions. Here, we investigated the neural underpinnings of object and space perception by combining the administration of the Visual Object Space Perception (VOSP) battery with a voxel-based lesion symptom mapping (VLSM) approach in a large sample of patients with penetrating traumatic brain injury (pTBI).

Prism adaptation in the healthy brain: the shift in line bisection judgments is long lasting and fluctuates.

Rightward prism adaptation has been shown to ameliorate visuospatial biases in right brain-damaged patients with neglect, and a single session of prism adaptation can lead to improvements that last up to several hours. Leftward prism adaptation in neurologically healthy individuals induces neglect-like biases in visuospatial tasks. The duration of these effects in healthy individuals, typically assumed to be ephemeral, has never been investigated.

Isolated theory of mind deficits and risk for frontotemporal dementia: a longitudinal pilot study.

Objective: Recent data suggest that theory of mind (ToM) deficits represent an early symptom of the behavioural variant of frontotemporal dementia (bvFTD). However, longitudinal data on the natural history of subjects presenting with isolated ToM deficits are lacking. The aim of the study was to verify if isolated ToM deficits represent an at-risk state for prefrontal dysfunction and bvFTD.

A voxel-based lesion study on facial emotion recognition after penetrating brain injury.

The ability to read emotions in the face of another person is an important social skill that can be impaired in subjects with traumatic brain injury (TBI). To determine the brain regions that modulate facial emotion recognition, we conducted a whole-brain analysis using a well-validated facial emotion recognition task and voxel-based lesion symptom mapping (VLSM) in a large sample of patients with focal penetrating TBIs (pTBIs). Our results revealed that individuals with pTBI performed significantly worse than normal controls in recognizing unpleasant emotions.

Severity of unilateral spatial neglect is an independent predictor of functional outcome after acute inpatient rehabilitation in individuals with right hemispheric stroke.

Objective: To investigate the relationship between severity of unilateral spatial neglect (USN) and functional recovery in activities of daily living after a right-hemisphere stroke.

Design: Observational study.

Setting: Rehabilitation hospital in Italy.