1,721,020 research outputs found
Specific effect of a cognitive-motor dual-task training on sport performance and brain processing associated with decision-making in semi-elite basketball players
No full textObjectives: In this study, we aimed at evaluating the effects of cognitive-motor dual-task training (CMDT) on sport-specific athletic performance and cognitive functions of semi-elite basketball players. Further, we investigated the CMDT effects on reactive brain processing by employing event-related potential (ERP) analysis. Design: A randomized controlled trial was conducted including 52 young semi-elite basketball players (28 females mean age 16.3 ± 1.1 years) who were randomly assigned into an experimental (Exp) group executing the CMDT and a control (Con) group performing standard motor training. Method: Athletes' sport-specific performance was evaluated with dribbling tests before and after a five-week training. Cognitive performance was assessed by measuring speed and accuracy in a discrimination response task. Brain activity associated with sensory processing, selective attention, and decision-making was measured through the P1, N1, and P3 components. The CMDT consisted of simultaneous execution of dribbling exercises and cognitive tasks which were realized using interactive devices located around the athlete on the basket court. Data were submitted to a mixed analysis of variance. Results: Both groups showed some improvements from pre-to post-tests, but the Exp group improved basket-specific performance by 13% more than the Con group; in addition, the cognitive performance also improved more in the Exp group (25.8% in accuracy and 5.4% response speed). According to the EEG results, training did not affect sensory processing and attentional processing which were equally increased after both kinds of training; however, decision-making processes were specifically affected by the experimental training. Conclusions: This study confirmed the effectiveness of the proposed CMDT protocol on both sport-specific and cognitive performance of basketball players and showed that the neural basis of these benefits may be mediated by more intense decisional processing allowing faster connection between sensory encoding and response execution
Electrophysiological sign of stronger auditory processing in females than males during passive listening
No full text: Available literature shows sex-related differences in both anatomy and functions of the auditory cortex. However, only few data are available on passive listening. By means of event-related potentials (ERPs), we analyzed the proactive and reactive stages of processing related to passive listening in 36 healthy young participants, equally balanced between genders. The anterior positivity (aP), a newly discovered pre-stimulus component originating in auditory cortices and indexing auditory readiness, was not different between genders; the post-stimulus components (the N1 and the N2, originating in primary and secondary auditory cortices) were larger in females than males. These results not only provide significant insights on sex-related differences during listening, but also encourage the potential use of passive tasks, which allow for better understanding of basic neural processing, without interferences from cognitive requirements of active tasks
Time Course of Reactive Brain Activities during a Stroop Color-Word Task: Evidence of Specific Facilitation and Interference Effects
No full text: The Stroop test represents a widely used task in basic and clinical research for approaching the cognitive system functioning in humans. However, a clear overview of the neurophysiological signatures associated with the different sub-domains of this task remains controversial. In the present study, we leveraged the EEG technique to explore the modulation of specific post-stimulus ERPs components during the Stroop test. Critically, to better disentangle the contribution of facilitation (i.e., faster color identification times for color-congruent Stroop words) and interference (i.e., longer color identification times for color-incongruent Stroop words) processes prompted by the Stroop test, we delivered congruent and incongruent trials in two separate experimental blocks, each including the respective neutral condition. Thanks to this methodological manipulation, we were able to clearly dissociate the two sub-processes. Electrophysiological results suggest specific markers of brain activity for the facilitation and the interference effects. Indeed, distinctive Stroop-related ERPs (i.e., the P3, the N450, and the LPC) were differently modulated in the two sub-processes. Collectively, we provide evidence of selected brain activities involved in the reactive stage of processing associated with the Stroop effect
Short-term monocular deprivation alters early components of visual evoked potentials
No full textVery little is known about plasticity in the adult visual cortex. In recent years psychophysical studies have shown that short-term monocular deprivation alters visual perception in adult humans. Specifically, after 150 min of monocular deprivation the deprived eye strongly dominates the dynamics of binocular rivalry, reflecting homeostatic plasticity. Here we investigate the neural mechanisms underlying this form of short-term visual cortical plasticity by measuring visual evoked potentials (VEPs) on the scalp of adult humans during monocular stimulation before and after 150 min of monocular deprivation. We found that monocular deprivation had opposite effects on the amplitude of the earliest component of the VEP (C1) for the deprived and non-deprived eye stimulation. C1 amplitude increased (+66%) for the deprived eye, while it decreased (-29%) for the non-deprived eye. Source localization analysis confirmed that the C1 originates in the primary visual cortex. We further report that following monocular deprivation, the amplitude of the peak of the evoked alpha spectrum increased on average by 23% for the deprived eye and decreased on average by 10% for the non-deprived eye, indicating a change in cortical excitability. These results indicate that a brief period of monocular deprivation alters interocular balance in the primary visual cortex of adult humans by both boosting the activity of the deprived eye and reducing the activity of the non-deprived eye. This indicates a high level of residual homeostatic plasticity in the adult human primary visual cortex, probably mediated by a change in cortical excitability
Different proactive and reactive action control in fencers’ and boxers’ brain
No full text: Practicing sport at top level requires excellent physical and cognitive skills. The goal of the present study was to investigate whether specific sport practice may affect the preparation-perception-action stages of processing during a visuo-motor task requiring perceptual discrimination and fast response. We recruited 39 participants (two groups of professional fencers and boxers, and a control group; N=13 for each group) and measured behavioral performance and event-related potentials (ERPs) while performing a go/no-go task. Results revealed that athletes were faster than controls, while fencers were more accurate than boxers. ERP analysis revealed that motor preparation, indexed by the Bereitschaftspotential (BP), was increased in athletes than controls, whereas the top-down attentional control, reflected by the prefrontal negativity (pN) component, was enhanced only in fencers when compared to controls. Most of the post-stimulus ERPs i.e. the N1, the N2, the P3, and the pP2, were enhanced in fencers. Combat sports require fast action execution, but the preparatory brain activity might differ according to the specific practice required by each discipline. Boxers might afford to commit more errors (as reflected by high commission error (CE) rate and by a small pN amplitude), while fencers have to be as much fast and accurate as possible (thanks to an enhanced pN amplitude). Although the possible influence of repetitive head blows on cerebral activity cannot be excluded in boxers, our results suggest that cognitive benefits of high-level sport practice might also be transferred to the daily (i.e., no sport-related) activities
Now You See One Letter, Now You See Meaningless Symbols: Perceptual and Semantic Hypnotic Suggestions Reduce Stroop Errors Through Different Neurocognitive Mechanisms
No full text: Compelling literature has suggested the possibility of adopting hypnotic suggestions to override the Stroop interference effect. However, most of these studies mainly reported behavioral data and were conducted on highly hypnotizable individuals. Thus, the question of the neural locus of the effects and their generalizability remains open. In the present study, we used the Stroop task in a within-subject design to test the neurocognitive effects of two hypnotic suggestions: the perceptual request to focus only on the central letter of the words and the semantic request to observe meaningless symbols. Behavioral results indicated that the two types of suggestions did not alter response time (RT), but both favored more accurate performance compared to the control condition. Both types of suggestions increased sensory awareness and reduced discriminative visual attention, but the perceptual request selectively engaged more executive control of the prefrontal cortex (PFC), and the semantic request selectively suppressed the temporal cortex activity devoted to graphemic analysis of the words. The present findings demonstrated that the perceptual and the semantic hypnotic suggestions reduced Stroop errors through common and specific top-down modulations of different neurocognitive processes but left the semantic activation unaltered. Finally, as we also recruited participants with a medium level of hypnotizability, the present data might be considered potentially representative of the majority of the population
Illusory and veridical mapping of tactile objects in the primary somatosensory and posterior parietal cortex
No full textWhile several behavioral and neuroscience studies have explored visual, auditory, and cross-modal illusions, information about the phenomenology and neural correlates of somatosensory illusions is meager. By combining psychophysics and somatosensory evoked potentials, we explored in healthy humans the neural correlates of 2 compelling tactuo-proprioceptive illusions, namely Aristotle (1 object touching the contact area between 2 crossed fingers is perceived as 2 lateral objects) and Reverse illusions (2 lateral objects are perceived as 1 between crossed-fingers object). These illusions likely occur because of the tactuo-proprioceptive conflict induced by fingers being crossed in a non-natural posture. We found that different regions in the somatosensory stream exhibit different proneness to the illusions. Early electroencephalographic somatosensory activity (at 20 ms) originating in the primary somatosensory cortex (S1) reflects the phenomenal rather than the physical properties of the stimuli. Notably, later activity (around 200 ms) originating in the posterior parietal cortex is higher when subjects resist the illusions. Thus, while S1 activity is related to illusory perception, PPC acts as a conflict resolver that recodes tactile events from somatotopic to spatiotopic frames of reference and ultimately enables veridical perception
Electrophysiological evidence of phonemotopic representations of vowels in the primary and secondary auditory cortex
No full textHow the brain encodes the speech acoustic signal into phonological representations is a fundamental question for the neurobiology of language. Determining whether this process is characterized by tonotopic maps in primary or secondary auditory areas, with bilateral or leftward activity, remains a long-standing challenge. Magnetoencephalographic studies failed to show hierarchical and asymmetric hints for speech processing. We employed high-density electroencephalography to map the Salento Italian vowel system onto cortical sources using the N1 auditory evoked component. We found evidence that the N1 is characterized by hierarchical and asymmetrical indexes in primary and secondary auditory areas structuring vowel representations. Importantly, the N1 was characterized by early and late phases. The early N1 peaked at 125–135 msec and was localized in the primary auditory cortex; the late N1 peaked at 145–155 msec and was localized in the left superior temporal gyrus. We showed that early in the primary auditory cortex, the cortical spatial arrangements—along the lateral-medial and anterior-posterior gradients—are broadly warped by phonemotopic patterns according to the distinctive feature principle. These phonemotopic patterns are carefully refined in the superior temporal gyrus along the inferior-superior and anterior-posterior gradients. The dynamical and hierarchical interface between primary and secondary auditory areas and the interaction effects between Height and Place features generate the categorical representation of the Salento Italian vowels
Effects of a Cognitive-Motor Training on Anticipatory Brain Functions and Sport Performance in Semi-Elite Basketball Players
No full textThe aim of this research was to test the possible effects of cognitive–motor training (CMT) on athletes’ sport performance and cognitive functions. Namely, specific athletic tests, brain processes associated with anticipatory event-related potential (ERP) components and behavioral performance during a cognitive discrimination response task were evaluated pre- and post-training. Twenty-four young semi-professional basketball players were recruited for the study and randomly divided into an experimental (Exp) group executing the CMT training and a control (Con) group performing standard motor training. The CMT training protocol included exercises in which participants performed cognitive tasks during dribbling exercises using interactive devices which emitted visual and auditory stimuli, in which athletes’ responses were recorded. Results showed that following training, only the Exp group improved in all sport-specific tests (17%) and more than the Con group (88% vs. 60%) in response accuracy during the cognitive test. At brain level, post-training anticipatory cognitive processes associated with proactive inhibition and top-down attention in the prefrontal cortex were earlier and heightened in the Exp group. Our findings confirm previous studies on clear improved efficacy of CMT training protocols on sport performance and cognition compared to training based on motor exercises only, but extend the literature in showing that these effects might be explained by enhanced anticipatory brain processing in the prefrontal cortex. The present study also suggests that in order to achieve specific athletic goals, the brain adapts cognitive functions by means of neuroplasticity processes
Modality predictability modulation confirms the sensorial readiness function of the pre-stimulus activity in sensory brain areas
No full text: The auditory Positivity (aP) and the visual Negativity (vN) are recently discovered modality-specific event-related potential (ERP) components associated with sensory readiness, which seems promising to study anticipatory perception and attention. However, a crucial aspect of these waves remains to be determined since it is still unclear if these components are indeed related to sensory readiness or represent the result of stimulus predictably. Indeed, earlier studies found these components in tasks where stimuli were repeatedly presented uniquely in the same sensory modality. To disentangle this issue, we used an experimental design consisting of three passive tasks: a unimodal auditory condition, a unimodal visual condition, and an intermodal condition in which the visual and auditory stimuli were unpredictably alternated. Then, we compared the amplitudes of the aP and vN in the three conditions and performed correlation analyses between pre-stimulus and post-stimulus components. Crucially, results showed that in the intermodal condition the components still occur, but their amplitudes are decreased compared to unimodal condition, providing evidence that they are only partially dependent on the task and that expectancy might modulate them. This result is in line with the "modality-shift effect" costs phenomenon which can occur also for passive tasks even before stimulus presentation. In addition, the amplitude of the post-stimulus components correlated with pre-stimulus ERP. Collectively, the present study confirms that the aP and the vN reflect sensory readiness processes that "boost" post-stimulus auditory N1 and visual P1 components
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