37 results on '"Bottari D"'
Search Results
2. Esperienze atipiche nel corso dello sviluppo
- Author
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Nava, E, Bottari, D, Nava, E, and Bottari, D
- Published
- 2019
3. High vowel processing in deaf Italian children with unilateral cochlear implants: a behavioral and neurophysiological study
- Author
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Garrapa L., Bottari D., Calabrese A., Pavani F., De Benedetto, Vitale V., Monastero P., Greco M., GRIMALDI, Milko Antonino, Vincenzo Galatà, Garrapa, L., Bottari, D., Grimaldi, Milko Antonino, Calabrese, A., Pavani, F., De, Benedetto, Vitale, V., Monastero, P., and Greco, M.
- Published
- 2013
4. High vowel processing in deaf Italian children with unilateral cochlear implants: A neurophysiologic and behavioral study
- Author
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Garrapa L., Bottari D., Calabarese A., Pavani F., De Benedetto M., Vitale S., Monastero P., Greco M., GRIMALDI, Milko Antonino, Garrapa, L., Bottari, D., Grimaldi, Milko Antonino, Calabarese, A., Pavani, F., De Benedetto, M., Vitale, S., Monastero, P., and Greco, M.
- Subjects
otorhinolaryngologic diseases - Abstract
Cochlear implants partially restore auditory sensation in individuals affected by severe to profound hearing loss. We investigated vowel detection, identification, and discrimination in a group of congenitally-deafened, unilaterally-implanted, Italian children and in a group of age-matched controls, by combining behavioral and neurophysiologic measures. Comparable vowel identification and discrimination performance emerged for cochlear-implant and normal- hearing ch ildren at the behavioral level. At the neurophysiologic level, on the other hand, cochlear-implant children appeared to lag behind their age-matched normal- hearing peers for vowel detection and identification, but not for vowel discrimination. Length of cochlear implant use sign ificantly affected vowel processing at the neurophysiologic level, although not systematically.
- Published
- 2013
5. Detection, identification, and discrimination of /i/, /u/, and /ɛ/ in Italian cochlear-implant children: a behavioral and neurophysiological study
- Author
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1.9. Garrapa L., Bottari D., Pavani F., Calabrese A., De Benedetto M., Vitale S., GRIMALDI, Milko Antonino, 1. 9. Garrapa, L., Bottari, D., Pavani, F., Calabrese, A., De Benedetto, M., Vitale, S., and Grimaldi, Milko Antonino
- Published
- 2013
6. Audio-Tactile Integration in Congenitally and Late Deaf Cochlear Implant Users
- Author
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Nava, E, Bottari, D, Villwock, A, Fengler, I, Büchner, A, Lenarz, T, Röder, B, NAVA, ELENA HAE KYUNG, Röder, B., Nava, E, Bottari, D, Villwock, A, Fengler, I, Büchner, A, Lenarz, T, Röder, B, NAVA, ELENA HAE KYUNG, and Röder, B.
- Abstract
Several studies conducted in mammals and humans have shown that multisensory processing may be impaired following congenital sensory loss and in particular if no experience is achieved within specific early developmental time windows known as sensitive periods. In this study we investigated whether basic multisensory abilities are impaired in hearing-restored individuals with deafness acquired at different stages of development. To this aim, we tested congenitally and late deaf cochlear implant (CI) recipients, age-matched with two groups of hearing controls, on an audio-tactile redundancy paradigm, in which reaction times to unimodal and crossmodal redundant signals were measured. Our results showed that both congenitally and late deaf CI recipients were able to integrate audio-tactile stimuli, suggesting that congenital and acquired deafness does not prevent the development and recovery of basic multisensory processing. However, we found that congenitally deaf CI recipients had a lower multisensory gain compared to their matched controls, which may be explained by their faster responses to tactile stimuli. We discuss this finding in the context of reorganisation of the sensory systems following sensory loss and the possibility that these changes cannot be "rewired" through auditory reafferentation. © 2014 Nava et al.
- Published
- 2014
7. Enhanced reactivity to visual stimuli in deaf individuals
- Author
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Bottari, D, Nava, E, Ley, P, Pavani, F, NAVA, ELENA HAE KYUNG, Pavani, F., Bottari, D, Nava, E, Ley, P, Pavani, F, NAVA, ELENA HAE KYUNG, and Pavani, F.
- Abstract
Purpose: Several studies have reported faster response time to visual stimuli in profoundly deaf individuals. This result is often linked to the processing of peripheral targets, and it is assumed to occur in relation to attention orienting. We evaluated whether enhanced reactivity to visual events in profoundly deaf individuals can be explained by faster orienting of visual attention alone. Methods: We examined 11 deaf individuals and 11 hearing controls, in a simple detection task and in a shape discrimination task. While simple detection can be performed under distributed attention, shape discrimination requires orienting of spatial attention to the target. The same visual targets served for both tasks, presented at central or peripheral locations and corrected for cortical magnification. Results: The simple detection task revealed faster RTs in deaf than hearing controls, regardless of target location. Moreover, while hearing controls paid a cost in responding to peripheral than central targets, deaf participants performed equally well regardless of target eccentricity. In the shape discrimination task deaf never outperformed hearing controls. Conclusions: These findings reveal that enhanced reactivity to visual stimuli in the deaf cannot be explained only by faster orienting of visual attention and can emerge for centr l as well as peripheral targets. Moreover, the persisting advantage for peripheral locations in the deaf, observed here under distributed attention, suggests that this spatially-selective effect could result from reorganised sensory processing rather than different attentional gradients. © 2010 - IOS Press and the authors. All rights reserved.
- Published
- 2010
8. Hearing again with two ears: Recovery of spatial hearing after bilateral cochlear implantation
- Author
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Nava, E, Bottari, D, Portioli, G, Bonfioli, F, Beltrame, M, Formigoni, P, Pavani, F, NAVA, ELENA HAE KYUNG, Beltrame, MA, Pavani, F., Nava, E, Bottari, D, Portioli, G, Bonfioli, F, Beltrame, M, Formigoni, P, Pavani, F, NAVA, ELENA HAE KYUNG, Beltrame, MA, and Pavani, F.
- Abstract
Bilateral cochlear implants (CI) offer a unique opportunity for the study of spatial hearing plasticity in humans. Here we studied the recovery of spatial hearing in two sequential bilateral CI recipients, adopting a longitudinal approach. Each recipient was tested in a sound-source identification task shortly after bilateral activation and at 1, 6, and 12 months follow-up. The results show fast recovery (1 month from CI activation) in the recipient who had substantial experience with auditory cues in adulthood. By contrast, the bilateral CI recipient who developed profound deafness in childhood, regained spatial hearing abilities only 12 months after CI activation. These findings provide the first direct evidence that recovery of auditory spatial abilities in bilateral CI recipients can occur shortly after activation of the two devices. In addition, they suggest that previous auditory experience can constrain the time course of this recovery. © 2008 Elsevier Ltd. All rights reserved.
- Published
- 2009
9. Spatial hearing with a single cochlear implant in late-implanted adults
- Author
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Nava, E, Bottari, D, Bonfioli, F, Beltrame, M, Pavani, F, NAVA, ELENA HAE KYUNG, Beltrame, MA, Pavani, F., Nava, E, Bottari, D, Bonfioli, F, Beltrame, M, Pavani, F, NAVA, ELENA HAE KYUNG, Beltrame, MA, and Pavani, F.
- Abstract
We assessed sound localisation abilities of late-implanted adults fitted with a single cochlear implant (CI) and examined whether these abilities are affected by the duration of implant use. Ten prelingually and four postlingually deafened adults who received a unilateral CI were tested in a sound-source identification task. Above chance performance was observed in those prelingual CI recipients who had worn their implant for longer time (9 years on average), revealing some monaural sound localisation abilities in this population but only after extensive CI use. On the contrary, the four postlingual recipients performed equal or better with respect to the best prelingual participants despite shorter experience with the monaural implant (11 months on average). Our findings reveal that some sound localisation ability can emerge in prelingually deafened adults fitted with a single implant, at least in a controlled laboratory setting. This ability, however, appears to emerge only after several years of CI use. Furthermore, the results of four postlingually deafened adults suggest that early experience with auditory cues may result in more rapid acquisition of spatial hearing with a single CI. © 2009 Elsevier B.V. All rights reserved.
- Published
- 2009
10. Hearing again with two ears: recovery of spatial hearing after cochlear implantation
- Author
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Nava, E, Bottari, D, Pavani, F, Nava, E, Bottari, D, and Pavani, F
- Published
- 2008
11. Space and time modulate faster visual detection in the profound deaf
- Author
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Bottari, D, Nava, E, Ley, Pavani, F, Bottari, D, Nava, E, Ley, and Pavani, F
- Published
- 2008
12. Fast recovery of binaural spatial hearing in a bilateral cochlear implant recipient
- Author
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Nava, E, Bottari, D, Bonfioli, F, Beltrame, M, Portioli, G, Formigoni, P, Pavani, F, Beltrame, MA, Nava, E, Bottari, D, Bonfioli, F, Beltrame, M, Portioli, G, Formigoni, P, Pavani, F, and Beltrame, MA
- Published
- 2008
13. Visual temporal order judgment in profoundly deaf individuals
- Author
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Nava, E, Bottari, D, Zampini, M, Pavani, F, NAVA, ELENA HAE KYUNG, Pavani, F., Nava, E, Bottari, D, Zampini, M, Pavani, F, NAVA, ELENA HAE KYUNG, and Pavani, F.
- Abstract
We investigated temporal processing in profoundly deaf individuals by testing their ability to make temporal order judgments (TOJs) for pairs of visual stimuli presented at central or peripheral visual eccentricities. Ten profoundly deaf participants judged which of the two visual stimuli appearing on opposite sides of central fixation was delivered first. Stimuli were presented either symmetrically, at central or peripheral locations, or asymmetrically (i.e. one central and the other peripheral) at varying stimulus onset asynchronies (SOAs) using the method of constant stimuli. Two groups of hearing controls were also tested in this task: 10 hearing controls auditory-deprived during testing and 12 hearing controls who were not subjected to any deprivation procedure. Temporal order thresholds (i.e. just noticeable differences) and points of subjective simultaneity for the two visual stimuli did not differ between groups. However, faster discrimination responses were systematically observed in the deaf than in either group of hearing controls, especially when the first of the two stimuli appeared at peripheral locations. Contrary to some previous findings, our results show that a life-long auditory deprivation does not alter temporal processing abilities in the millisecond range. In fact, we show that deaf participants obtain similar temporal thresholds to hearing controls, while also responding much faster. This enhanced reactivity is documented here for the first time in the context of a temporal processing task, and we suggest it may constitute a critical aspect of the functional changes occurring as a consequence of profound deafness. © 2008 Springer-Verlag.
- Published
- 2008
14. Comparable visual temporal-order-judgment abilities in profoundly deaf and normal-hearing individuals
- Author
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Nava, E, Bottari, D, Zampini, M, Pavani, F, Nava, E, Bottari, D, Zampini, M, and Pavani, F
- Published
- 2007
15. Audiovisual integration in patients with visual deficit
- Author
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Frassinetti, F, Bolognini, N, Bottari, D, Bonora, A, Làdavas, E, Làdavas, E., BOLOGNINI, NADIA, Frassinetti, F, Bolognini, N, Bottari, D, Bonora, A, Làdavas, E, Làdavas, E., and BOLOGNINI, NADIA
- Abstract
In the present study, we investigated the possibility that bimodal audiovisual stimulation of the affected hemifield can improve perception of the visual events in the blind hemifield of hemianopic patients, as it was previously demonstrated in neglect patients. Moreover, it has been shown that ‘‘heteromodal’’ and ‘‘sensory-specific’’ cortices are involved in crossmodal integration. Thus, the second aim of the present study was to examine whether audiovisual integration influences visual detection in patients with different cortical lesions responsible of different kinds of visual disorders. More specifically, we investigated cross-modal, audiovisual integration in patients with visual impairment due to a visual field deficit (e.g., hemianopia) or visuospatial attentional deficit (e.g., neglect) and patients with both hemianopia and neglect. Patients were asked to detect visual stimuli presented alone or in combination with auditory stimuli that could be spatially aligned or not with the visual ones. The results showed an enhancement of visual detection in cross-modal condition (spatially aligned condition) comparing to unimodal visual condition only in patients with hemianopia or neglect; by contrast, the multisensory integration did not occur when patients presented both deficits. These data suggest that patients with visual disorders can enormously benefit the multisensory integration. Moreover, they showed a different influence of cortical lesion on multisensory integration. Thus, the present results show the important adaptive meaning of multisensory integration and are very promising with respect to the possibility of recovery from visual and spatial impairments
- Published
- 2005
16. Audiovisual Integration in Patients with Visual Deficit
- Author
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Elisabetta Làdavas, Annalisa Bonora, Francesca Frassinetti, Nadia Bolognini, Davide Bottari, Frassinetti, F, Bolognini, N, Bottari, D, Bonora, A, and Làdavas, E
- Subjects
Male ,Auditory perception ,medicine.medical_specialty ,Signal Detection, Psychological ,Visual perception ,genetic structures ,Cognitive Neuroscience ,media_common.quotation_subject ,Visual impairment ,Spatial Behavior ,Audiology ,M-PSI/02 - PSICOBIOLOGIA E PSICOLOGIA FISIOLOGICA ,multisensory, neglect, hemianopia ,Neglect ,Perceptual Disorders ,Reaction Time ,medicine ,Humans ,Contrast (vision) ,Attention ,Hemianopsia ,Aged ,Retrospective Studies ,media_common ,Cerebral Cortex ,Analysis of Variance ,Multisensory integration ,medicine.disease ,eye diseases ,Acoustic Stimulation ,Auditory Perception ,Visual Perception ,Female ,medicine.symptom ,Psychology ,Neuroscience ,Photic Stimulation - Abstract
In the present study, we investigated the possibility that bimodal audiovisual stimulation of the affected hemifield can improve perception of the visual events in the blind hemifield of hemianopic patients, as it was previously demonstrated in neglect patients. Moreover, it has been shown that “hetero-modal” and “sensory-specific” cortices are involved in cross-modal integration. Thus, the second aim of the present study was to examine whether audiovisual integration influences visual detection in patients with different cortical lesions responsible of different kinds of visual disorders. More specifically, we investigated cross-modal, audiovisual integration in patients with visual impairment due to a visual field deficit (e.g., hemianopia) or visuospatial attentional deficit (e.g., neglect) and patients with both hemianopia and neglect. Patients were asked to detect visual stimuli presented alone or in combination with auditory stimuli that could be spatially aligned or not with the visual ones. The results showed an enhancement of visual detection in cross-modal condition (spatially aligned condition) comparing to unimodal visual condition only in patients with hemianopia or neglect; by contrast, the multi-sensory integration did not occur when patients presented both deficits. These data suggest that patients with visual disorders can enormously benefit the multisensory integration. Moreover, they showed a different influence of cortical lesion on multi-sensory integration. Thus, the present results show the important adaptive meaning of multisensory integration and are very promising with respect to the possibility of recovery from visual and spatial impairments.
- Published
- 2005
17. Audio-tactile integration in congenitally and late deaf cochlear implant users
- Author
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Elena Nava, Brigitte Röder, Davide Bottari, Andreas Büchner, Thomas Lenarz, Agnes Villwock, Ineke Fengler, Nava, E, Bottari, D, Villwock, A, Fengler, I, Büchner, A, Lenarz, T, and Röder, B
- Subjects
Male ,medicine.medical_treatment ,lcsh:Medicine ,audio-tactile integration, cochlear implants, congenital and late deafness, plasticity, brain, sensitive periods ,Audiology ,Deafness ,0302 clinical medicine ,Hearing ,Time windows ,Cochlear implant ,Human Performance ,Psychology ,10. No inequality ,lcsh:Science ,Multidisciplinary ,Crossmodal ,05 social sciences ,Sensory loss ,Experimental Psychology ,Middle Aged ,Sensory Systems ,Auditory System ,Female ,Sensory Perception ,Research Article ,Adult ,medicine.medical_specialty ,Sensory system ,Context (language use) ,050105 experimental psychology ,Tactile stimuli ,03 medical and health sciences ,Young Adult ,Neuropsychology ,Sensitive periods ,medicine ,otorhinolaryngologic diseases ,Reaction Time ,Humans ,0501 psychology and cognitive sciences ,Behavior ,lcsh:R ,Biology and Life Sciences ,Cochlear Implants ,Persons With Hearing Impairments ,Touch ,lcsh:Q ,Sensory Deprivation ,030217 neurology & neurosurgery ,Neuroscience - Abstract
Several studies conducted in mammals and humans have shown that multisensory processing may be impaired following congenital sensory loss and in particular if no experience is achieved within specific early developmental time windows known as sensitive periods. In this study we investigated whether basic multisensory abilities are impaired in hearing-restored individuals with deafness acquired at different stages of development. To this aim, we tested congenitally and late deaf cochlear implant (CI) recipients, age-matched with two groups of hearing controls, on an audio-tactile redundancy paradigm, in which reaction times to unimodal and crossmodal redundant signals were measured. Our results showed that both congenitally and late deaf CI recipients were able to integrate audio-tactile stimuli, suggesting that congenital and acquired deafness does not prevent the development and recovery of basic multisensory processing. However, we found that congenitally deaf CI recipients had a lower multisensory gain compared to their matched controls, which may be explained by their faster responses to tactile stimuli. We discuss this finding in the context of reorganisation of the sensory systems following sensory loss and the possibility that these changes cannot be "rewired" through auditory reafferentation. © 2014 Nava et al.
- Published
- 2014
18. Brain Encoding of Naturalistic, Continuous, and Unpredictable Tactile Events.
- Author
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Castellani N, Federici A, Fantoni M, Ricciardi E, Garbarini F, and Bottari D
- Subjects
- Humans, Male, Female, Young Adult, Adult, Brain physiology, Fingers physiology, Touch physiology, Evoked Potentials, Somatosensory physiology, Brain Mapping, Functional Laterality physiology, Electroencephalography methods, Touch Perception physiology, Physical Stimulation
- Abstract
Studies employing EEG to measure somatosensory responses have been typically optimized to compute event-related potentials in response to discrete events. However, tactile interactions involve continuous processing of nonstationary inputs that change in location, duration, and intensity. To fill this gap, this study aims to demonstrate the possibility of measuring the neural tracking of continuous and unpredictable tactile information. Twenty-seven young adults (females, 15) were continuously and passively stimulated with a random series of gentle brushes on single fingers of each hand, which were covered from view. Thus, tactile stimulations were unique for each participant and stimulated fingers. An encoding model measured the degree of synchronization between brain activity and continuous tactile input, generating a temporal response function (TRF). Brain topographies associated with the encoding of each finger stimulation showed a contralateral response at central sensors starting at 50 ms and peaking at ∼140 ms of lag, followed by a bilateral response at ∼240 ms. A series of analyses highlighted that reliable tactile TRF emerged after just 3 min of stimulation. Strikingly, topographical patterns of the TRF allowed discriminating digit lateralization across hands and digit representation within each hand. Our results demonstrated for the first time the possibility of using EEG to measure the neural tracking of a naturalistic, continuous, and unpredictable stimulation in the somatosensory domain. Crucially, this approach allows the study of brain activity following individualized, idiosyncratic tactile events to the fingers., Competing Interests: The authors declare no competing financial interests., (Copyright © 2024 Castellani et al.)
- Published
- 2024
- Full Text
- View/download PDF
19. Dissecting abstract, modality-specific and experience-dependent coding of affect in the human brain.
- Author
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Lettieri G, Handjaras G, Cappello EM, Setti F, Bottari D, Bruno V, Diano M, Leo A, Tinti C, Garbarini F, Pietrini P, Ricciardi E, and Cecchetti L
- Subjects
- Humans, Photic Stimulation, Prefrontal Cortex, Brain Mapping methods, Magnetic Resonance Imaging, Brain, Emotions
- Abstract
Emotion and perception are tightly intertwined, as affective experiences often arise from the appraisal of sensory information. Nonetheless, whether the brain encodes emotional instances using a sensory-specific code or in a more abstract manner is unclear. Here, we answer this question by measuring the association between emotion ratings collected during a unisensory or multisensory presentation of a full-length movie and brain activity recorded in typically developed, congenitally blind and congenitally deaf participants. Emotional instances are encoded in a vast network encompassing sensory, prefrontal, and temporal cortices. Within this network, the ventromedial prefrontal cortex stores a categorical representation of emotion independent of modality and previous sensory experience, and the posterior superior temporal cortex maps the valence dimension using an abstract code. Sensory experience more than modality affects how the brain organizes emotional information outside supramodal regions, suggesting the existence of a scaffold for the representation of emotional states where sensory inputs during development shape its functioning.
- Published
- 2024
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20. Sound suppresses earliest visual cortical processing after sight recovery in congenitally blind humans.
- Author
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Sourav S, Kekunnaya R, Bottari D, Shareef I, Pitchaimuthu K, and Röder B
- Subjects
- Humans, Visual Perception, Sound, Thalamus, Blindness, Visual Cortex
- Abstract
Neuroscientific research has consistently shown more extensive non-visual activity in the visual cortex of congenitally blind humans compared to sighted controls; a phenomenon known as crossmodal plasticity. Whether or not crossmodal activation of the visual cortex retracts if sight can be restored is still unknown. The present study, involving a rare group of sight-recovery individuals who were born pattern vision blind, employed visual event-related potentials to investigate persisting crossmodal modulation of the initial visual cortical processing stages. Here we report that the earliest, stimulus-driven retinotopic visual cortical activity (<100 ms) was suppressed in a spatially specific manner in sight-recovery individuals when concomitant sounds accompanied visual stimulation. In contrast, sounds did not modulate the earliest visual cortical response in two groups of typically sighted controls, nor in a third control group of sight-recovery individuals who had suffered a transient phase of later (rather than congenital) visual impairment. These results provide strong evidence for persisting crossmodal activity in the visual cortex after sight recovery following a period of congenital visual deprivation. Based on the time course of this modulation, we speculate on a role of exuberant crossmodal thalamic input which may arise during a sensitive phase of brain development., (© 2024. The Author(s).)
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- 2024
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21. Distinguishing Fine Structure and Summary Representation of Sound Textures from Neural Activity.
- Author
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Berto M, Ricciardi E, Pietrini P, Weisz N, and Bottari D
- Subjects
- Humans, Acoustic Stimulation, Sound, Evoked Potentials, Auditory physiology, Acoustics, Auditory Perception physiology, Auditory Cortex physiology
- Abstract
The auditory system relies on both local and summary representations; acoustic local features exceeding system constraints are compacted into a set of summary statistics. Such compression is pivotal for sound-object recognition. Here, we assessed whether computations subtending local and statistical representations of sounds could be distinguished at the neural level. A computational auditory model was employed to extract auditory statistics from natural sound textures (i.e., fire, rain) and to generate synthetic exemplars where local and statistical properties were controlled. Twenty-four human participants were passively exposed to auditory streams while the electroencephalography (EEG) was recorded. Each stream could consist of short, medium, or long sounds to vary the amount of acoustic information. Short and long sounds were expected to engage local or summary statistics representations, respectively. Data revealed a clear dissociation. Compared with summary-based ones, auditory-evoked responses based on local information were selectively greater in magnitude in short sounds. Opposite patterns emerged for longer sounds. Neural oscillations revealed that local features and summary statistics rely on neural activity occurring at different temporal scales, faster (beta) or slower (theta-alpha). These dissociations emerged automatically without explicit engagement in a discrimination task. Overall, this study demonstrates that the auditory system developed distinct coding mechanisms to discriminate changes in the acoustic environment based on fine structure and summary representations., Competing Interests: The authors declare no competing financial interests., (Copyright © 2023 Berto et al.)
- Published
- 2023
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22. Altered neural oscillations underlying visuospatial processing in cerebral visual impairment.
- Author
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Federici A, Bennett CR, Bauer CM, Manley CE, Ricciardi E, Bottari D, and Merabet LB
- Abstract
Visuospatial processing deficits are commonly observed in individuals with cerebral visual impairment, even in cases where visual acuity and visual field functions are intact. Cerebral visual impairment is a brain-based visual disorder associated with the maldevelopment of central visual pathways and structures. However, the neurophysiological basis underlying higher-order perceptual impairments in this condition has not been clearly identified, which in turn poses limits on developing rehabilitative interventions. Using combined eye tracking and EEG recordings, we assessed the profile and performance of visual search on a naturalistic virtual reality-based task. Participants with cerebral visual impairment and controls with neurotypical development were instructed to search, locate and fixate on a specific target placed among surrounding distractors at two levels of task difficulty. We analysed evoked (phase-locked) and induced (non-phase-locked) components of broadband (4-55 Hz) neural oscillations to uncover the neurophysiological basis of visuospatial processing. We found that visual search performance in cerebral visual impairment was impaired compared to controls (as indexed by outcomes of success rate, reaction time and gaze error). Analysis of neural oscillations revealed markedly reduced early-onset evoked theta [4-6 Hz] activity (within 0.5 s) regardless of task difficulty. Moreover, while induced alpha activity increased with task difficulty in controls, this modulation was absent in the cerebral visual impairment group identifying a potential neural correlate related to deficits with visual search and distractor suppression. Finally, cerebral visual impairment participants also showed a sustained induced gamma response [30-45 Hz]. We conclude that impaired visual search performance in cerebral visual impairment is associated with substantial alterations across a wide range of neural oscillation frequencies. This includes both evoked and induced components suggesting the involvement of feedforward and feedback processing as well as local and distributed levels of neural processing., Competing Interests: The authors report no competing interests., (Published by Oxford University Press on behalf of the Guarantors of Brain 2023.)
- Published
- 2023
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23. The development of oscillatory and aperiodic resting state activity is linked to a sensitive period in humans.
- Author
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Ossandón JP, Stange L, Gudi-Mindermann H, Rimmele JM, Sourav S, Bottari D, Kekunnaya R, and Röder B
- Subjects
- Adult, Humans, Blindness congenital, Electroencephalography, Vision Disorders, Visual Cortex, Cataract, Eye Abnormalities
- Abstract
Congenital blindness leads to profound changes in electroencephalographic (EEG) resting state activity. A well-known consequence of congenital blindness in humans is the reduction of alpha activity which seems to go together with increased gamma activity during rest. These results have been interpreted as indicating a higher excitatory/inhibitory (E/I) ratio in visual cortex compared to normally sighted controls. Yet it is unknown whether the spectral profile of EEG during rest would recover if sight were restored. To test this question, the present study evaluated periodic and aperiodic components of the EEG resting state power spectrum. Previous research has linked the aperiodic components, which exhibit a power-law distribution and are operationalized as a linear fit of the spectrum in log-log space, to cortical E/I ratio. Moreover, by correcting for the aperiodic components from the power spectrum, a more valid estimate of the periodic activity is possible. Here we analyzed resting state EEG activity from two studies involving (1) 27 permanently congenitally blind adults (CB) and 27 age-matched normally sighted controls (MCB); (2) 38 individuals with reversed blindness due to bilateral, dense, congenital cataracts (CC) and 77 age-matched sighted controls (MCC). Based on a data driven approach, aperiodic components of the spectra were extracted for the low frequency (Lf-Slope 1.5 to 19.5 Hz) and high frequency (Hf-Slope 20 to 45 Hz) range. The Lf-Slope of the aperiodic component was significantly steeper (more negative slope), and the Hf-Slope of the aperiodic component was significantly flatter (less negative slope) in CB and CC participants compared to the typically sighted controls. Alpha power was significantly reduced, and gamma power was higher in the CB and the CC groups. These results suggest a sensitive period for the typical development of the spectral profile during rest and thus likely an irreversible change in the E/I ratio in visual cortex due to congenital blindness. We speculate that these changes are a consequence of impaired inhibitory circuits and imbalanced feedforward and feedback processing in early visual areas of individuals with a history of congenital blindness., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)
- Published
- 2023
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24. Crossmodal plasticity following short-term monocular deprivation.
- Author
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Federici A, Bernardi G, Senna I, Fantoni M, Ernst MO, Ricciardi E, and Bottari D
- Subjects
- Adult, Humans, Visual Perception, Sensory Deprivation physiology, Neuronal Plasticity physiology, Vision, Monocular physiology, Visual Cortex physiology
- Abstract
A brief period of monocular deprivation (MD) induces short-term plasticity of the adult visual system. Whether MD elicits neural changes beyond visual processing is yet unclear. Here, we assessed the specific impact of MD on neural correlates of multisensory processes. Neural oscillations associated with visual and audio-visual processing were measured for both the deprived and the non-deprived eye. Results revealed that MD changed neural activities associated with visual and multisensory processes in an eye-specific manner. Selectively for the deprived eye, alpha synchronization was reduced within the first 150 ms of visual processing. Conversely, gamma activity was enhanced in response to audio-visual events only for the non-deprived eye within 100-300 ms after stimulus onset. The analysis of gamma responses to unisensory auditory events revealed that MD elicited a crossmodal upweight for the non-deprived eye. Distributed source modeling suggested that the right parietal cortex played a major role in neural effects induced by MD. Finally, visual and audio-visual processing alterations emerged for the induced component of the neural oscillations, indicating a prominent role of feedback connectivity. Results reveal the causal impact of MD on both unisensory (visual and auditory) and multisensory (audio-visual) processes and, their frequency-specific profiles. These findings support a model in which MD increases excitability to visual events for the deprived eye and audio-visual and auditory input for the non-deprived eye., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interests., (Copyright © 2023. Published by Elsevier Inc.)
- Published
- 2023
- Full Text
- View/download PDF
25. Interactions between auditory statistics processing and visual experience emerge only in late development.
- Author
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Berto M, Ricciardi E, Pietrini P, and Bottari D
- Abstract
The auditory system relies on local and global representations to discriminate sounds. This study investigated whether vision influences the development and functioning of these fundamental sound computations. We employed a computational approach to control statistical properties embedded in sounds and tested samples of sighted controls (SC) and congenitally (CB) and late-onset (LB) blind individuals in two experiments. In experiment 1, performance relied on local features analysis; in experiment 2, performance benefited from computing global representations. In both experiments, SC and CB performance remarkably overlapped. Conversely, LB performed systematically worse than the other groups when relying on local features, with no alterations on global representations. Results suggest that auditory computations tested here develop independently from vision. The efficiency of local auditory processing can be hampered in case sight becomes unavailable later in life, supporting the existence of an audiovisual interplay for the processing of auditory details, which emerges only in late development., Competing Interests: The authors declare no competing interests., (© 2021 The Author(s).)
- Published
- 2021
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26. The size-weight illusion is unimpaired in individuals with a history of congenital visual deprivation.
- Author
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Pant R, Guerreiro MJS, Ley P, Bottari D, Shareef I, Kekunnaya R, and Röder B
- Subjects
- Adolescent, Adult, Child, Female, Humans, Male, Perioperative Period, Treatment Outcome, Visual Acuity, Young Adult, Sensory Deprivation, Size Perception, Visual Perception, Visually Impaired Persons, Weight Perception
- Abstract
Visual deprivation in childhood can lead to lifelong impairments in multisensory processing. Here, the Size-Weight Illusion (SWI) was used to test whether visuo-haptic integration recovers after early visual deprivation. Normally sighted individuals perceive larger objects to be lighter than smaller objects of the same weight. In Experiment 1, individuals treated for dense bilateral congenital cataracts (who had no patterned visual experience at birth), individuals treated for developmental cataracts (who had patterned visual experience at birth, but were visually impaired), congenitally blind individuals and normally sighted individuals had to rate the weight of manually explored cubes that differed in size (Small, Medium, Large) across two possible weights (350 g, 700 g). In Experiment 2, individuals treated for dense bilateral congenital cataracts were compared to sighted individuals in a similar task using a string set-up, which removed haptic size cues. In both experiments, indistinguishable SWI effects were observed across all groups. These results provide evidence that early aberrant vision does not interfere with the development of the SWI, and suggest a recovery of the integration of size and weight cues provided by the visual and haptic modality.
- Published
- 2021
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27. EEG frequency-tagging demonstrates increased left hemispheric involvement and crossmodal plasticity for face processing in congenitally deaf signers.
- Author
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Bottari D, Bednaya E, Dormal G, Villwock A, Dzhelyova M, Grin K, Pietrini P, Ricciardi E, Rossion B, and Röder B
- Subjects
- Adult, Brain Waves, Deafness congenital, Facial Expression, Female, Functional Laterality, Humans, Male, Photic Stimulation, Sign Language, Young Adult, Brain physiopathology, Deafness physiopathology, Electroencephalography, Facial Recognition physiology, Neuronal Plasticity, Signal Processing, Computer-Assisted
- Abstract
In humans, face-processing relies on a network of brain regions predominantly in the right occipito-temporal cortex. We tested congenitally deaf (CD) signers and matched hearing controls (HC) to investigate the experience dependence of the cortical organization of face processing. Specifically, we used EEG frequency-tagging to evaluate: (1) Face-Object Categorization, (2) Emotional Facial-Expression Discrimination and (3) Individual Face Discrimination. The EEG was recorded to visual stimuli presented at a rate of 6 Hz, with oddball stimuli at a rate of 1.2 Hz. In all three experiments and in both groups, significant face discriminative responses were found. Face-Object categorization was associated to a relative increased involvement of the left hemisphere in CD individuals compared to HC individuals. A similar trend was observed for Emotional Facial-Expression discrimination but not for Individual Face Discrimination. Source reconstruction suggested a greater activation of the auditory cortices in the CD group for Individual Face Discrimination. These findings suggest that the experience dependence of the relative contribution of the two hemispheres as well as crossmodal plasticity vary with different aspects of face processing., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interests., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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28. Biological Action Identification Does Not Require Early Visual Input for Development.
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Rajendran SS, Bottari D, Shareef I, Pitchaimuthu K, Sourav S, Troje NF, Kekunnaya R, and Röder B
- Subjects
- Humans, Motion, Movement, Visual Acuity, Motion Perception
- Abstract
Visual input during the first years of life is vital for the development of numerous visual functions. While normal development of global motion perception seems to require visual input during an early sensitive period, the detection of biological motion (BM) does not seem to do so. A more complex form of BM processing is the identification of human actions. Here, we tested whether identification rather than detection of BM is experience dependent. A group of human participants who had been treated for congenital cataracts (CC; of up to 18 years in duration, CC group) had to identify ten actions performed by human line figures. In addition, they performed a coherent motion (CM) detection task, which required identifying the direction of CM amid the movement of random dots. As controls, developmental cataract (DC) reversal individuals (DC group) who had undergone the same surgical treatment as CC group were included. Moreover, normally sighted controls were tested both with vision blurred to match the visual acuity (VA) of CC individuals [vision matched (VM) group] and with full sight [sighted control (SC) group]. The CC group identified biological actions with an extraordinary high accuracy (on average ∼85% correct) and was indistinguishable from the VM control group. By contrast, CM processing impairments of the CC group persisted even after controlling for VA. These results in the same individuals demonstrate an impressive resilience of BM processing to aberrant early visual experience and at the same time a sensitive period for the development of CM processing., (Copyright © 2020 Rajendran et al.)
- Published
- 2020
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29. An electrophysiological biomarker for the classification of cataract-reversal patients: A case-control study.
- Author
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Sourav S, Bottari D, Shareef I, Kekunnaya R, and Röder B
- Abstract
Background: Untreated congenital blindness through cataracts leads to lasting visual brain system changes, including substantial alterations of extrastriate visual areas. Consequently, late-treated individuals (> 5 months of age) with dense congenital bilateral cataracts (CC) exhibit poorer visual function recovery compared to individuals with bilateral developmental cataracts (DC). Reliable methods to differentiate between patients with congenital and developmental cataracts are often lacking, impeding efficient rehabilitation management and introducing confounds in clinical and basic research on recovery prognosis and optimal timing of surgery. A persistent reduction of the P1 wave of visual event-related potentials (VERPs), associated with extrastriate visual cortical activity, has been reported in CC but not in DC individuals. Using two experiments, this study developed and validated P1-based biomarkers for diagnosing a history of congenital blindness in cataract-reversal individuals., Methods: Congenital and developmental cataract-reversal individuals as well as typically sighted matched controls took part in a first experiment used for exploring an electrophysiological biomarker ( N
CC = 13, NDC = 13, NControl = 26). Circular stimuli containing gratings were presented in one of the visual field quadrants while visual event-related potentials (VERPs) were recorded. Two biomarkers were derived from the P1 wave of the VERP: (1) The mean of the normalized P1 amplitude at posterior electrodes, and (2) a classifier obtained from a linear support vector machine (SVM). A second experiment with partially new CC/DC individuals and their matched controls ( NCC = 14, NDC = 15, NControl = 29) was consecutively used to validate the classification based on both biomarkers. Performance of the classifiers were evaluated using receiver operating characteristic (ROC) curve analyses. All cataract-reversal individuals were tested after at least one year of vision recovery., Findings: The normalized P1 amplitude over posterior electrodes allowed a successful classification of the CC from the DC individuals and typically sighted controls (area under ROC curve, AUC = 0.803 and 0.929 for the normalized P1 amplitude and the SVM-based biomarker, respectively). The validation for both biomarkers in experiment 2 again resulted in a high classification success (AUC = 0.800 and 0.883, respectively for the normalized P1 amplitude and the SVM-based biomarker). In the most conservative scenario involving classification of CC from DC individuals in a group of only cataract-reversal individuals, excluding typically sighted controls, the SVM-based biomarker was found to be superior to the mean P1 amplitude based biomarker (AUC = 0.852 compared to 0.757 for the mean P1 based biomarker in validation). Minimum specificity obtained was 80% across all biomarkers., Interpretation: A persistent reduction of the P1 wave provides a highly specific method for classifying cataract patients post-surgically as having suffered from bilateral congenital vs. bilateral developmental cataracts. We suggest that using the P1 based non-invasive electrophysiological biomarker will augment existing clinical classification criteria for individuals with a history of bilateral congenital cataracts, aiding clinical and basic research, recovery prognosis, and rehabilitation efforts., Funding: German Research Foundation (DFG) and the European Research Council (ERC)., Competing Interests: All authors report grants from the German Research Foundation (DFG) and the European Research Council (ERC) during the conduct of the study., (© 2020 The Author(s).)- Published
- 2020
- Full Text
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30. Evidence of a retinotopic organization of early visual cortex but impaired extrastriate processing in sight recovery individuals.
- Author
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Sourav S, Bottari D, Kekunnaya R, and Röder B
- Subjects
- Adolescent, Adult, Animals, Cataract Extraction, Child, Electroencephalography, Female, Humans, Male, Visual Acuity physiology, Visual Fields physiology, Visual Pathways physiology, Young Adult, Cataract congenital, Recovery of Function physiology, Retina physiology, Vision Disorders physiopathology, Visual Cortex physiology
- Abstract
Numerous studies in visually deprived nonhuman animals have demonstrated sensitive periods for the functional development of the early visual cortex. However, in humans it is yet unknown which visual areas are shaped to which degree based on visual experience. The present study investigated the functional organization and processing capacities of early visual cortex in sight recovery individuals with either a history of congenital cataracts (CC) or late onset cataracts (developmental cataracts, DC). Visual event-related potentials (VERPs) were recorded to grating stimuli which were flashed in one of the four quadrants of the visual field. Participants had to detect rarely occurring grating orientations. The CC individuals showed the expected polarity reversal of the C1 wave between upper and lower visual field stimuli at the typical latency range. Since the C1 has been proposed to originate in the early retinotopic visual cortex, we concluded that one basic feature of the retinotopic organization, upper versus lower visual field organization, is spared in CC individuals. Group differences in the size and topography of the C1 effect, however, suggested a less precise functional tuning. The P1 wave, which has been associated with extrastriate visual cortex processing, was significantly attenuated in CC but not in DC individuals compared to typically sighted controls. The present study thus provides evidence for fundamental aspects of retinotopic processing in humans being independent of developmental vision. We suggest that visual impairments in sight recovery individuals may predominantly arise at higher cortical processing stages.
- Published
- 2018
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31. Sight restoration after congenital blindness does not reinstate alpha oscillatory activity in humans.
- Author
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Bottari D, Troje NF, Ley P, Hense M, Kekunnaya R, and Röder B
- Subjects
- Adolescent, Adult, Blindness physiopathology, Blindness surgery, Child, Electroencephalography, Evoked Potentials, Visual, Female, Humans, Male, Photic Stimulation, Task Performance and Analysis, Young Adult, Blindness congenital, Vision, Ocular
- Abstract
Functional brain development is characterized by sensitive periods during which experience must be available to allow for the full development of neural circuits and associated behavior. Yet, only few neural markers of sensitive period plasticity in humans are known. Here we employed electroencephalographic recordings in a unique sample of twelve humans who had been blind from birth and regained sight through cataract surgery between four months and 16 years of age. Two additional control groups were tested: a group of visually impaired individuals without a history of total congenital blindness and a group of typically sighted individuals. The EEG was recorded while participants performed a visual discrimination task involving intact and scrambled biological motion stimuli. Posterior alpha and theta oscillations were evaluated. The three groups showed indistinguishable behavioral performance and in all groups evoked theta activity varied with biological motion processing. By contrast, alpha oscillatory activity was significantly reduced only in individuals with a history of congenital cataracts. These data document on the one hand brain mechanisms of functional recovery (related to theta oscillations) and on the other hand, for the first time, a sensitive period for the development of alpha oscillatory activity in humans.
- Published
- 2016
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32. Audio-tactile integration in congenitally and late deaf cochlear implant users.
- Author
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Nava E, Bottari D, Villwock A, Fengler I, Büchner A, Lenarz T, and Röder B
- Subjects
- Adult, Deafness congenital, Deafness etiology, Deafness surgery, Female, Humans, Male, Middle Aged, Reaction Time, Young Adult, Cochlear Implants, Deafness physiopathology, Hearing physiology, Persons With Hearing Impairments, Touch physiology
- Abstract
Several studies conducted in mammals and humans have shown that multisensory processing may be impaired following congenital sensory loss and in particular if no experience is achieved within specific early developmental time windows known as sensitive periods. In this study we investigated whether basic multisensory abilities are impaired in hearing-restored individuals with deafness acquired at different stages of development. To this aim, we tested congenitally and late deaf cochlear implant (CI) recipients, age-matched with two groups of hearing controls, on an audio-tactile redundancy paradigm, in which reaction times to unimodal and crossmodal redundant signals were measured. Our results showed that both congenitally and late deaf CI recipients were able to integrate audio-tactile stimuli, suggesting that congenital and acquired deafness does not prevent the development and recovery of basic multisensory processing. However, we found that congenitally deaf CI recipients had a lower multisensory gain compared to their matched controls, which may be explained by their faster responses to tactile stimuli. We discuss this finding in the context of reorganisation of the sensory systems following sensory loss and the possibility that these changes cannot be "rewired" through auditory reafferentation.
- Published
- 2014
- Full Text
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33. ERP correlates of German Sign Language processing in deaf native signers.
- Author
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Hänel-Faulhaber B, Skotara N, Kügow M, Salden U, Bottari D, and Röder B
- Subjects
- Adult, Female, Germany, Humans, Male, Statistics as Topic, Young Adult, Brain physiology, Cognition physiology, Deafness physiopathology, Deafness rehabilitation, Evoked Potentials physiology, Semantics, Sign Language, Task Performance and Analysis
- Abstract
Background: The present study investigated the neural correlates of sign language processing of Deaf people who had learned German Sign Language (Deutsche Gebärdensprache, DGS) from their Deaf parents as their first language. Correct and incorrect signed sentences were presented sign by sign on a computer screen. At the end of each sentence the participants had to judge whether or not the sentence was an appropriate DGS sentence. Two types of violations were introduced: (1) semantically incorrect sentences containing a selectional restriction violation (implausible object); (2) morphosyntactically incorrect sentences containing a verb that was incorrectly inflected (i.e., incorrect direction of movement). Event-related brain potentials (ERPs) were recorded from 74 scalp electrodes., Results: Semantic violations (implausible signs) elicited an N400 effect followed by a positivity. Sentences with a morphosyntactic violation (verb agreement violation) elicited a negativity followed by a broad centro-parietal positivity., Conclusions: ERP correlates of semantic and morphosyntactic aspects of DGS clearly differed from each other and showed a number of similarities with those observed in other signed and oral languages. These data suggest a similar functional organization of signed and oral languages despite the visual-spacial modality of sign language.
- Published
- 2014
- Full Text
- View/download PDF
34. Sensitive periods for the functional specialization of the neural system for human face processing.
- Author
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Röder B, Ley P, Shenoy BH, Kekunnaya R, and Bottari D
- Subjects
- Adolescent, Adult, Blindness, Cataract, Child, Female, Humans, Male, Face, Models, Neurological, Nerve Net, Visual Perception
- Abstract
The aim of the study was to identify possible sensitive phases in the development of the processing system for human faces. We tested the neural processing of faces in 11 humans who had been blind from birth and had undergone cataract surgery between 2 mo and 14 y of age. Pictures of faces and houses, scrambled versions of these pictures, and pictures of butterflies were presented while event-related potentials were recorded. Participants had to respond to the pictures of butterflies (targets) only. All participants, even those who had been blind from birth for several years, were able to categorize the pictures and to detect the targets. In healthy controls and in a group of visually impaired individuals with a history of developmental or incomplete congenital cataracts, the well-known enhancement of the N170 (negative peak around 170 ms) event-related potential to faces emerged, but a face-sensitive response was not observed in humans with a history of congenital dense cataracts. By contrast, this group showed a similar N170 response to all visual stimuli, which was indistinguishable from the N170 response to faces in the controls. The face-sensitive N170 response has been associated with the structural encoding of faces. Therefore, these data provide evidence for the hypothesis that the functional differentiation of category-specific neural representations in humans, presumably involving the elaboration of inhibitory circuits, is dependent on experience and linked to a sensitive period. Such functional specialization of neural systems seems necessary to archive high processing proficiency.
- Published
- 2013
- Full Text
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35. Botulinum neurotoxin A impairs neurotransmission following retrograde transynaptic transport.
- Author
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Restani L, Novelli E, Bottari D, Leone P, Barone I, Galli-Resta L, Strettoi E, and Caleo M
- Subjects
- Animals, Calcium Signaling, Rats, Rats, Long-Evans, Retinal Neurons drug effects, Retinal Neurons metabolism, Retinal Neurons ultrastructure, Synaptic Transmission physiology, Synaptic Vesicles drug effects, Synaptic Vesicles ultrastructure, Synaptosomal-Associated Protein 25 metabolism, Botulinum Toxins, Type A pharmacology, Synaptic Transmission drug effects, Synaptic Vesicles metabolism, Synaptosomal-Associated Protein 25 antagonists & inhibitors
- Abstract
The widely used botulinum neurotoxin A (BoNT/A) blocks neurotransmission via cleavage of the synaptic protein SNAP-25 (synaptosomal-associated protein of 25 kDa). Recent evidence demonstrating long-distance propagation of SNAP-25 proteolysis has challenged the idea that BoNT/A remains localized to the injection site. However, the extent to which distant neuronal networks are impacted by BoNT/A retrograde trafficking remains unknown. Importantly, no studies have addressed whether SNAP-25 cleavage translates into structural and functional changes in distant intoxicated synapses. Here we show that the BoNT/A injections into the adult rat optic tectum result in SNAP-25 cleavage in retinal neurons two synapses away from the injection site, such as rod bipolar cells and photoreceptors. Retinal endings displaying cleaved SNAP-25 were enlarged and contained an abnormally high number of synaptic vesicles, indicating impaired exocytosis. Tectal injection of BoNT/A in rat pups resulted in appearance of truncated-SNAP-25 in cholinergic amacrine cells. Functional imaging with calcium indicators showed a clear reduction in cholinergic-driven wave activity, demonstrating impairments in neurotransmission. These data provide the first evidence for functional effects of the retrograde trafficking of BoNT/A, and open the possibility of using BoNT/A fragments as drug delivery vehicles targeting the central nervous system., (© 2012 John Wiley & Sons A/S.)
- Published
- 2012
- Full Text
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36. Changes in early cortical visual processing predict enhanced reactivity in deaf individuals.
- Author
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Bottari D, Caclin A, Giard MH, and Pavani F
- Subjects
- Adolescent, Adult, Behavior physiology, Evoked Potentials, Visual, Female, Hearing physiology, Humans, Male, Middle Aged, Photic Stimulation, Time Factors, Young Adult, Deafness physiopathology, Visual Cortex physiology
- Abstract
Individuals with profound deafness rely critically on vision to interact with their environment. Improvement of visual performance as a consequence of auditory deprivation is assumed to result from cross-modal changes occurring in late stages of visual processing. Here we measured reaction times and event-related potentials (ERPs) in profoundly deaf adults and hearing controls during a speeded visual detection task, to assess to what extent the enhanced reactivity of deaf individuals could reflect plastic changes in the early cortical processing of the stimulus. We found that deaf subjects were faster than hearing controls at detecting the visual targets, regardless of their location in the visual field (peripheral or peri-foveal). This behavioural facilitation was associated with ERP changes starting from the first detectable response in the striate cortex (C1 component) at about 80 ms after stimulus onset, and in the P1 complex (100-150 ms). In addition, we found that P1 peak amplitudes predicted the response times in deaf subjects, whereas in hearing individuals visual reactivity and ERP amplitudes correlated only at later stages of processing. These findings show that long-term auditory deprivation can profoundly alter visual processing from the earliest cortical stages. Furthermore, our results provide the first evidence of a co-variation between modified brain activity (cortical plasticity) and behavioural enhancement in this sensory-deprived population.
- Published
- 2011
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37. Audiovisual integration in patients with visual deficit.
- Author
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Frassinetti F, Bolognini N, Bottari D, Bonora A, and Làdavas E
- Subjects
- Acoustic Stimulation methods, Aged, Analysis of Variance, Attention physiology, Cerebral Cortex anatomy & histology, Female, Humans, Male, Photic Stimulation methods, Reaction Time physiology, Retrospective Studies, Spatial Behavior, Auditory Perception physiology, Cerebral Cortex physiopathology, Perceptual Disorders physiopathology, Signal Detection, Psychological physiology, Visual Perception physiology
- Abstract
In the present study, we investigated the possibility that bimodal audiovisual stimulation of the affected hemifield can improve perception of the visual events in the blind hemifield of hemianopic patients, as it was previously demonstrated in neglect patients. Moreover, it has been shown that "hetero-modal" and "sensory-specific" cortices are involved in cross-modal integration. Thus, the second aim of the present study was to examine whether audiovisual integration influences visual detection in patients with different cortical lesions responsible of different kinds of visual disorders. More specifically, we investigated cross-modal, audiovisual integration in patients with visual impairment due to a visual field deficit (e.g., hemianopia) or visuospatial attentional deficit (e.g., neglect) and patients with both hemianopia and neglect. Patients were asked to detect visual stimuli presented alone or in combination with auditory stimuli that could be spatially aligned or not with the visual ones. The results showed an enhancement of visual detection in cross-modal condition (spatially aligned condition) comparing to unimodal visual condition only in patients with hemianopia or neglect; by contrast, the multisensory integration did not occur when patients presented both deficits. These data suggest that patients with visual disorders can enormously benefit the multisensory integration. Moreover, they showed a different influence of cortical lesion on multisensory integration. Thus, the present results show the important adaptive meaning of multisensory integration and are very promising with respect to the possibility of recovery from visual and spatial impairments.
- Published
- 2005
- Full Text
- View/download PDF
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