Search results for " Photic Stimulation"
showing 9 items of 19 documents
Developmental Trajectories of Internally and Externally Driven Temporal Prediction.
2015
The ability to generate temporal prediction (TP) is fundamental to our survival since it allows us to selectively orient our attention in time in order to prioritize relevant environmental information. Studies on adult participants showed that externally and internally driven mechanisms can be engaged to establish TP, both resulting in better behavioural performance. However, few studies on children have investigated the ability to engage internally and externally driven TP, especially in relation to how these mechanisms change across development. In this study, 111 participants (88 children between six and eleven years of age, and 23 adults) were tested by means of a simple reaction time p…
RELATIVISTIC COMPRESSION AND EXPANSION OF EXPERIENTIAL TIME IN THE LEFT AND RIGHT SPACE
2007
Time, space and numbers are closely linked in the physical world. However, the relativistic-like effects on time perception of spatial and magnitude factors remain poorly investigated. Here we wanted to investigate whether duration judgments of digit visual stimuli are biased depending on the side of space where the stimuli are presented and on the magnitude of the stimulus itself. Different groups of healthy subjects performed duration judgment tasks on various types of visual stimuli. In the first two experiments visual stimuli were constituted by digit pairs (1 and 9), presented in the centre of the screen or in the right and left space. In a third experiment visual stimuli were constitu…
The polymodal sensory cortex is crucial for controlling lateral postural stability: evidence from stroke patients.
2000
International audience; In modern literature, internal models are considered as a general neural process for resolving sensory ambiguities, synthesising information from disparate sensory modalities, and combining efferent and afferent information. The polymodal sensory cortex, especially the temporoparietal junction (TPJ), is thought to be a nodal point of the network underlying these properties. According to this view, a pronounced disruption of the TPJ functioning should dramatically impair body balance. Surprisingly, little attention has been paid to this possible relationship, which was the subject of investigation in this study. Twenty-two brain-damaged patients and 14 healthy subject…
Age-related differences in a delayed pointing of a M�ller-Lyer illusion
2003
It has been suggested that movements to visible or remembered targets are differently sensitive to the Müller-Lyer (ML) illusion. Indeed, when the target is continuously visible, movements rely on the veridical object characteristics, whereas remembered movements are thought to reflect the perceived characteristics of the object. The aim of the present study was to determine how movements to visible or remembered targets are influenced by the ML illusion in children aged 7 to 11 years old. Participants were asked to make a perceptual judgment or to point a shaft extremity of the ML configurations (Closed, Control, and Open) in three visual conditions (Closed Loop, Open Loop-0-s delay, and 5…
''Motor Resonance Mechanisms Are Preserved In Alzheimer's Disease Patients''
2012
Bisio, A. | Casteran, M. | Ballay, Y. | Manckoundia, P. | Mourey, F. | Pozzo, T.; International audience; ''This study aimed to better characterize the sensorimotor mechanisms underlying motor resonance, namely the relationship between motion perception and movement production in patients suffering from Alzheimer's disease (AD). This work first gives a kinematic description of AD patients' upper limb movements, then it presents a simple paradigm in which a dot with different velocities is moved in front of the participant who is instructed to point to its final position when it stopped. AD patients' actions, as well as healthy elderly participants, were similarly influenced by the dot veloc…
Resonance of cortico-cortical connections of the motor system with the observation of goal directed grasping movements
2010
Goal directed movements require the activation of parietal, premotor and primary motor areas. In monkeys, neurons of these areas become active also during the observation of movements performed by others, especially for coding the goal of the action (mirror system). Using bifocal transcranial magnetic stimulation (TMS) in healthy subjects, we tested whether the observation of goal directed reach to grasp actions may lead to specific changes in the short-latency connections linking key areas of the mirror system, such as the anterior intraparietal cortex (AIP) and the ventral premotor cortex (PMv), with the primary motor cortex (M1). We found that AIP-M1 and PMv-M1 cortico-cortical interacti…
The columnar gene vnd is required for tritocerebral neuromere formation during embryonic brain development of Drosophila.
2006
International audience; In Drosophila, evolutionarily conserved transcription factors are required for the specification of neural lineages along the anteroposterior and dorsoventral axes, such as Hox genes for anteroposterior and columnar genes for dorsoventral patterning. In this report, we analyse the role of the columnar patterning gene ventral nervous system defective (vnd) in embryonic brain development. Expression of vnd is observed in specific subsets of cells in all brain neuromeres. Loss-of-function analysis focussed on the tritocerebrum shows that inactivation of vnd results in regionalized axonal patterning defects, which are comparable with the brain phenotype caused by mutatio…
Subliminal fear priming potentiates negative facial reactions to food pictures in women with anorexia nervosa.
2010
BackgroundTo investigate hedonic reactivity and the influence of unconscious emotional processes on the low sensitivity to positive reinforcement of food in anorexia nervosa (AN).MethodAN and healthy women were exposed to palatable food pictures just after a subliminal exposure to facial expressions (happy, disgust, fear and neutral faces), either while fasting or after a standardized meal (hungerversussatiety). Both implicit [facial electromyographic (EMG) activity from zygomatic and corrugator muscles, skin conductance, heart rate, and videotaped facial behavior] and explicit (self-reported pleasure and desire) measures of affective processes were recorded.ResultsIn contrast to healthy wo…
A Preliminary Study on Photic Driving in the Electroencephalogram of Children with Autism across a Wide Cognitive and Behavioral Range.
2022
Intermittent photic stimulation (IPS) is a useful technique in electroencephalography (EEG) to investigate the neurophysiological anomalies of brain activity. Although not an active task, IPS has also been explored in ASD; it is thought to capture local potential oscillators at specific frequencies and perhaps tap into rhythmic activity in a way that general resting-state recordings cannot. Previous studies suggest that individuals with ASD showed photic driving reactivity predominantly at lower frequencies of stimulation. In our study we used IPS to measure rhythmic oscillatory activity in a sample of 81 ASD children. We found a significant correlation linking ASD children with photic driv…