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Article ; Online: Role of corpus callosum in unconscious vision.

Sanchez-Lopez, Javier / Cardobi, Nicolo / Parisi, Giorgia / Savazzi, Silvia / Marzi, Carlo A

2024 Volume 196, Page(s) 108839

Abstract: The existence of unconscious visually triggered behavior in patients with cortical blindness (e.g., homonymous hemianopia) has been amply demonstrated and the neural bases of this phenomenon have been thoroughly studied. However, a crosstalk between the ... ...

Abstract	The existence of unconscious visually triggered behavior in patients with cortical blindness (e.g., homonymous hemianopia) has been amply demonstrated and the neural bases of this phenomenon have been thoroughly studied. However, a crosstalk between the two hemispheres as a possible mechanism of unconscious or partially conscious vision has not been so far considered. Thus, the aim of this study was to assess the relationship between structural and functional properties of the corpus callosum (CC), as shown by probabilistic tractography (PT), behavioral detection/discrimination performance and level of perceptual awareness in the blind field of patients with hemianopia. Twelve patients were tested in two tasks with black-and-white visual square-wave gratings, one task of movement and the other of orientation. The stimuli were lateralized to one hemifield either intact or blind. A PT analysis was carried out on MRI data to extract fiber properties along the CC (genu, body, and splenium). Compared with a control group of participants without brain damage, patients showed lower FA values in all three CC sections studied. For the intact hemifield we found a significant correlation between PT values and visual detection/discrimination accuracy. For the blind hemifield the level of perceptual awareness correlated with PT values for all three CC sections in the movement task. Importantly, significant differences in all three CC sections were found also between patients with above-vs. chance detection/discrimination performance while differences in the genu were found between patients with and without perceptual awareness. Overall, our study provides evidence that the properties of CC fibers are related to the presence of unconscious stimulus detection/discrimination and to hints of perceptual awareness for stimulus presentation to the blind hemifield. These results underline the importance of information exchange between the damaged and the healthy hemisphere for possible partial or full recovery from hemianopia.
MeSH term(s)	Humans ; Hemianopsia/diagnostic imaging ; Corpus Callosum/diagnostic imaging ; Visual Perception ; Blindness, Cortical ; Unconsciousness ; Photic Stimulation
Language	English
Publishing date	2024-02-23
Publishing country	England
Document type	Journal Article
ZDB-ID	207151-4
ISSN	1873-3514 ; 0028-3932
ISSN (online)	1873-3514
ISSN	0028-3932
DOI	10.1016/j.neuropsychologia.2024.108839
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Article ; Online: Resting-state functional connectivity in multiple sclerosis patients receiving nabiximols for spasticity.

Gajofatto, Alberto / Cardobi, Nicolò / Gobbin, Francesca / Calabrese, Massimiliano / Turatti, Marco / Benedetti, Maria Donata

BMC neurology

2023 Volume 23, Issue 1, Page(s) 128

Abstract: Background: Nabiximols (Sativex®) is a cannabinoid approved for multiple sclerosis (MS)-related spasticity. Its mechanism of action is partially understood, and efficacy is variable.: Objective: To conduct an exploratory analysis of brain networks ... ...

Abstract	Background: Nabiximols (Sativex®) is a cannabinoid approved for multiple sclerosis (MS)-related spasticity. Its mechanism of action is partially understood, and efficacy is variable. Objective: To conduct an exploratory analysis of brain networks connectivity changes on resting state (RS) functional MRI (fMRI) of MS patients treated with nabiximols. Methods: We identified a group of MS patients treated with Sativex® at Verona University Hospital, who underwent RS brain fMRI in the 4 weeks before (T0) and 4-8 weeks after (T1) treatment start. Sativex® response was defined as ≥ 20% spasticity Numerical Rating Scale score reduction at T1 vs. T0. Connectivity changes on fMRI were compared between T0 and T1 in the whole group and according to response status. ROI-to-ROI and seed-to-voxel connectivity were evaluated. Results: Twelve MS patients (7 males) were eligible for the study. Seven patients (58.3%) resulted Sativex® responders at T1. On fMRI analysis, Sativex® exposure was associated with global brain connectivity increase (particularly in responders), decreased connectivity of motor areas, and bidirectional connectivity changes of the left cerebellum with a number of cortical areas. Conclusions: Nabiximols administration is associated with brain connectivity increase of MS patients with spasticity. Modulation of sensorimotor cortical areas and cerebellum connectivity could play a role in nabiximols effect.
MeSH term(s)	Male ; Humans ; Multiple Sclerosis/diagnostic imaging ; Multiple Sclerosis/drug therapy ; Cannabidiol/therapeutic use ; Dronabinol/therapeutic use ; Cannabinoids ; Drug Combinations ; Muscle Spasticity/diagnostic imaging ; Muscle Spasticity/drug therapy
Chemical Substances	nabiximols (K4H93P747O) ; Cannabidiol (19GBJ60SN5) ; Dronabinol (7J8897W37S) ; Cannabinoids ; Drug Combinations
Language	English
Publishing date	2023-03-29
Publishing country	England
Document type	Journal Article
ZDB-ID	2041347-6
ISSN	1471-2377 ; 1471-2377
ISSN (online)	1471-2377
ISSN	1471-2377
DOI	10.1186/s12883-023-03171-0
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Article ; Online: Path Tracing vs. Volume Rendering Technique in Post-Surgical Assessment of Bone Flap in Oncologic Head and Neck Reconstructive Surgery: A Preliminary Study.

Cardobi, Nicolò / Nocini, Riccardo / Molteni, Gabriele / Favero, Vittorio / Fior, Andrea / Marchioni, Daniele / Montemezzi, Stefania / D'Onofrio, Mirko

Journal of imaging

2023 Volume 9, Issue 2

Abstract: This study aims to compare a relatively novel three-dimensional rendering called Path Tracing (PT) to the Volume Rendering technique (VR) in the post-surgical assessment of head and neck oncologic surgery followed by bone flap reconstruction. This ... ...

Abstract	This study aims to compare a relatively novel three-dimensional rendering called Path Tracing (PT) to the Volume Rendering technique (VR) in the post-surgical assessment of head and neck oncologic surgery followed by bone flap reconstruction. This retrospective study included 39 oncologic patients who underwent head and neck surgery with free bone flap reconstructions. All exams were acquired using a 64 Multi-Detector CT (MDCT). PT and VR images were created on a dedicated workstation. Five readers, with different expertise in bone flap reconstructive surgery, independently reviewed the images (two radiologists, one head and neck surgeon and two otorhinolaryngologists, respectively). Every observer evaluated the images according to a 5-point Likert scale. The parameters assessed were image quality, anatomical accuracy, bone flap evaluation, and metal artefact. Mean and median values for all the parameters across the observer were calculated. The scores of both reconstruction methods were compared using a Wilcoxon matched-pairs signed rank test. Inter-reader agreement was calculated using Spearman's rank correlation coefficient. PT was considered significantly superior to VR 3D reconstructions by all readers (
Language	English
Publishing date	2023-01-20
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2824270-1
ISSN	2313-433X ; 2313-433X
ISSN (online)	2313-433X
ISSN	2313-433X
DOI	10.3390/jimaging9020024
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Article ; Online: Visuo-spatial attention to the blind hemifield of hemianopic patients: Can it survive the impairment of visual awareness?

Pedersini, Caterina A / Lingnau, Angelika / Sanchez-Lopez, Javier / Cardobi, Nicolo / Savazzi, Silvia / Marzi, Carlo A

Neuropsychologia

2020 Volume 149, Page(s) 107673

Abstract: The general aim of this study was to assess the effect produced by visuo-spatial attention on both behavioural performance and brain activation in hemianopic patients following visual stimulus presentation to the blind hemifield. To do that, we tested ... ...

Abstract	The general aim of this study was to assess the effect produced by visuo-spatial attention on both behavioural performance and brain activation in hemianopic patients following visual stimulus presentation to the blind hemifield. To do that, we tested five hemianopic patients and six age-matched healthy controls in an MRI scanner during the execution of a Posner-like paradigm using a predictive central cue. Participants were instructed to covertly orient attention toward the blind or sighted hemifield in different blocks while discriminating the orientation of a visual grating. In patients, we found significantly faster reaction times (RT) in valid and neutral than invalid trials not only in the sighted but also in the blind hemifield, despite the impairment of consciousness and performance at chance. As to the fMRI signal, in valid trials we observed the activation of ipsilesional visual areas (mainly lingual gyrus - area 19) during the orientation of attention toward the blind hemifield. Importantly, this activation was similar in patients and controls. In order to assess the related functional network, we performed a psychophysiological interactions (PPI) analysis that revealed an increased functional connectivity (FC) in patients with respect to controls between the ipsilesional lingual gyrus and ipsilateral fronto-parietal as well as contralesional parietal regions. Moreover, the shift of attention from the blind to the sighted hemifield revealed stronger FC between the contralesional visual areas V3/V4 and ipsilateral parietal regions in patients than controls. These results indicate a higher cognitive effort in patients when paying attention to the blind hemifiled or when shifting attention from the blind to the sighted hemfield, possibly as an attempt to compensate for the visual loss. Taken together, these results show that hemianopic patients can covertly orient attention toward the blind hemifield with a top-down mechanism by activating a functional network mainly including fronto-parietal regions belonging to the dorsal attentional network.
MeSH term(s)	Blindness/diagnostic imaging ; Functional Laterality ; Hemianopsia/diagnostic imaging ; Humans ; Magnetic Resonance Imaging ; Orientation ; Parietal Lobe ; Photic Stimulation ; Reaction Time ; Visual Perception
Language	English
Publishing date	2020-11-10
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	207151-4
ISSN	1873-3514 ; 0028-3932
ISSN (online)	1873-3514
ISSN	0028-3932
DOI	10.1016/j.neuropsychologia.2020.107673
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Article ; Online: Magnetic resonance imaging short protocols for intraductal papillary mucinous neoplasm (IPMN) surveillance: The time has come.

D'Onofrio, Mirko / Geraci, Luca / De Robertis, Riccardo Lombardi / Cardobi, Nicolò / Balduzzi, Alberto / Tomaiuolo, Luisa / Bardhi, Eda / Faccioli, Niccolò / Aluffi, Gregorio / Marchegiani, Giovanni / Salvia, Roberto

Digestive and liver disease : official journal of the Italian Society of Gastroenterology and the Italian Association for the Study of the Liver

2024

Abstract: Background/objectives: To analyze the diagnostic performance of three short magnetic resonance imaging (MRI) protocols for the follow-up of pancratic intraductal papillary mucinous neoplasms (IPMN).: Methods: Follow-up MRI examinations of 287 ... ...

Abstract	Background/objectives: To analyze the diagnostic performance of three short magnetic resonance imaging (MRI) protocols for the follow-up of pancratic intraductal papillary mucinous neoplasms (IPMN). Methods: Follow-up MRI examinations of 287 patients with IPMN performed in two centers were retrospectively retrieved. Four MRI protocols were identified as follows: T1-weighted (T1w), T2-weighted (T2w), and MRCP sequences (protocol 1); T1w, T2w, MRCP, and diffusion-weighted (DWI) sequences (protocol 2); T1w, T2w, MRCP, and post-contrast T1w-sequences (protocol 3); and a comprehensive protocol including all previous sequences (protocol 4). Three radiologists with different experience in abdominal imaging expressed their opinion upon the optimal patient's management upon the evaluation of each protocol. Intra-and inter-observer agreement and concordance with the clinical decision expressed by a pancreatic surgeon were calculated with Cohen's kappa test. Results: 223 patients were included (66±10 years; 92 men, 131 women). 143 patients had branch-duct-IPMNs, 25 main-duct-IPMNs and 55 mixed-type-IPMNs. 79 patients underwent surgery, resulting in 52 high-grade dysplasia (HGD) and 27 low-grade dysplasia (LGD). Concordance for the expert reader between protocols 1, 2 and 3 and the actual clinical decision were 0.63, 0.72, and 0.74 respectively (95% CI, 0.53-0.73, 0.63-0.81, and 0.65-0.83). Inter-observer agreement between reader 1 and reader 2, reader 1 and reader 3, and reader 2 and reader 3 were: 0.71, 0.50, and 0.75 for protocol 1 (95% CI, 0.63-0.81, 0.40-0.60, and 0.66-0.84);0.68, 0.54, and 0.84 for protocol 2 (95% CI, 0.59-0.77, 0.44-0.64, and 0.76-0.91); and 0.77, 0.65, and 0.86 for protocol 3 (95% CI, 0.69-0.86, 0.55-0.74, and 0.80-0.93). Conclusions: Short MRI protocol is suitable for IPMN surveillance.
Language	English
Publishing date	2024-04-12
Publishing country	Netherlands
Document type	Journal Article
ZDB-ID	1459373-7
ISSN	1878-3562 ; 1125-8055
ISSN (online)	1878-3562
ISSN	1125-8055
DOI	10.1016/j.dld.2024.03.005
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Article ; Online: CT radiomic models to distinguish COVID-19 pneumonia from other interstitial pneumonias.

Cardobi, Nicolò / Benetti, Giulio / Cardano, Giuseppe / Arena, Cinzia / Micheletto, Claudio / Cavedon, Carlo / Montemezzi, Stefania

La Radiologia medica

2021 Volume 126, Issue 8, Page(s) 1037–1043

Abstract: Purpose: To classify COVID-19, COVID-19-like and non-COVID-19 interstitial pneumonia using lung CT radiomic features.: Material and methods: CT data of 115 patients with respiratory symptoms suspected for COVID-19 disease were retrospectively ... ...

Abstract	Purpose: To classify COVID-19, COVID-19-like and non-COVID-19 interstitial pneumonia using lung CT radiomic features. Material and methods: CT data of 115 patients with respiratory symptoms suspected for COVID-19 disease were retrospectively analyzed. Based on the results of nasopharyngeal swab, patients were divided into two main groups, COVID-19 positive (C +) and COVID-19 negative (C-), respectively. C- patients, however, presented with interstitial lung involvement. A subgroup of C-, COVID-19-like (CL), were considered as highly suggestive of COVID pneumonia at CT. Radiomic features were extracted from the whole lungs. A dual machine learning (ML) model approach was used. The first one excluded CL patients from the training set, eventually included on the test set. The second model included the CL patients also in the training set. Results: The first model classified C + and C- pneumonias with AUC of 0.83. CL median response (0.80) was more similar to C + (0.92) compared to C- (0.17). Radiomic footprints of CL were similar to the C + ones (possibly false negative swab test). The second model, however, merging C + with CL patients in the training set, showed a slight decrease in classification performance (AUC = 0.81). Conclusion: Whole lung ML models based on radiomics can classify C + and C- interstitial pneumonia. This may help in the correct management of patients with clinical and radiological stigmata of COVID-19, however presenting with a negative swab test. CL pneumonia was similar to C + pneumonia, albeit with slightly different radiomic footprints.
MeSH term(s)	Adult ; Aged ; Aged, 80 and over ; COVID-19/diagnostic imaging ; Diagnosis, Differential ; Female ; Humans ; Lung Diseases, Interstitial/diagnostic imaging ; Male ; Middle Aged ; Models, Theoretical ; Retrospective Studies ; Tomography, X-Ray Computed
Language	English
Publishing date	2021-05-27
Publishing country	Italy
Document type	Journal Article
ZDB-ID	205751-7
ISSN	1826-6983 ; 0033-8362
ISSN (online)	1826-6983
ISSN	0033-8362
DOI	10.1007/s11547-021-01370-8
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Article ; Online: Neural bases of visual processing of moving and stationary stimuli presented to the blind hemifield of hemianopic patients.

Pedersini, Caterina A / Lingnau, Angelika / Cardobi, Nicolò / Sanchez-Lopez, Javier / Savazzi, Silvia / Marzi, Carlo A

Neuropsychologia

2020 Volume 141, Page(s) 107430

Abstract: Unilateral damage to post-chiasmatic visual pathways or cortical areas results in the loss of vision in the contralateral hemifield, known as hemianopia. Some patients, however, may retain the ability to perform an above chance unconscious detection or ... ...

Abstract	Unilateral damage to post-chiasmatic visual pathways or cortical areas results in the loss of vision in the contralateral hemifield, known as hemianopia. Some patients, however, may retain the ability to perform an above chance unconscious detection or discrimination of visual stimuli presented to the blind hemifield, known as "blindsight". An important finding in blindsight research is that it can often be elicited by moving stimuli. Therefore, in the present study, we wanted to test whether moving stimuli might yield blindsight phenomena in patients with cortical lesions resulting in hemianopia, in a discrimination task where stimulus movement is orthogonal to the feature of interest. This could represent an important strategy for rehabilitation because it might improve discrimination ability of stimulus features different but related to movement, e.g. line orientation. We tested eight hemianopic patients and eight age-matched healthy controls in an orientation discrimination task with moving or static visual stimuli. During performance of the task we carried out fMRI scanning and tractography. Behaviourally, we did not find a reliable main effect of motion on orientation discrimination; however, an important result was that in different patients blindsight could occur only with moving or stationary stimuli or with both. As to brain imaging results, following presentation of moving stimuli to the blind hemifield, a widespread fronto-parietal bilateral network was recruited including areas of the dorsal stream and in particular bilateral motion area hMT + whose activation positively correlated with behavioural performance. This bilateral network was not activated in controls suggesting that it represents a compensatory functional change following brain damage. Moreover, there was a higher activation of ipsilesional area hMT+ in patients who performed above chance in the moving condition. By contrast, in patients who performed above chance in the static condition, we found a higher activation of contralesional area V1 and extrastriate visual areas. Finally, we found a linear relationship between structural integrity of the ipsilesional pathway connecting lateral geniculate nucleus (LGN) with motion area hMT+ and both behavioural performance and ipsilesional hMT + activation. These results support the role of LGN in modulating performance as well as BOLD amplitude in the absence of visual awareness in ipsilesional area hMT+ during an orientation discrimination task with moving stimuli.
MeSH term(s)	Hemianopsia ; Humans ; Photic Stimulation ; Visual Cortex ; Visual Pathways/diagnostic imaging ; Visual Perception
Language	English
Publishing date	2020-03-12
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	207151-4
ISSN	1873-3514 ; 0028-3932
ISSN (online)	1873-3514
ISSN	0028-3932
DOI	10.1016/j.neuropsychologia.2020.107430
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Article ; Online: MRI-guided breast biopsy based on diffusion-weighted imaging: a feasibility study.

Montemezzi, Stefania / Cardano, Giuseppe / Storer, Silvia / Cardobi, Nicolò / Cavedon, Carlo / Camera, Lucia

European radiology

2020 Volume 31, Issue 5, Page(s) 2645–2656

Abstract: Objectives: This study evaluated the feasibility of DWI for lesion targeting in MRI-guided breast biopsies. Furthermore, it assessed device positioning on DWI during biopsy procedures.: Methods: A total of 87 biopsy procedures (5/87 bilateral) ... ...

Abstract	Objectives: This study evaluated the feasibility of DWI for lesion targeting in MRI-guided breast biopsies. Furthermore, it assessed device positioning on DWI during biopsy procedures. Methods: A total of 87 biopsy procedures (5/87 bilateral) consecutively performed between March 2019 and June 2020 were retrospectively reviewed: in these procedures, a preliminary DWI sequence (b = 1300 s/mm Results: Mass lesions ranged from 5 to 48 mm, with a mean size of 10.7 mm and a median size of 8 mm. Non-mass lesions ranged from 7 to 90 mm, with a mean size of 33.9 mm and a median size of 31 mm. Positioning of the coaxial system was confirmed on both T1-weighted and DWI sequences. At DWI, the biopsy needle was detectable in 62/64 (96.9%) cases; it was not visible in 2/64 (3.1%) cases. The site marker was always identified using T1-weighted imaging; a final DWI sequence was acquired in 44/64 cases (68.8%). In 42/44 cases (95.5%), the marker was recognizable at DWI. Conclusions: DWI can be used as a cost-effective, highly reliable technique for targeting both mass and non-mass lesions, with a minimum size of 5 mm, detectable at pre-procedural DWI. DWI is also a feasible technique to localize the biopsy device and to confirm the deployment of the site marker. Key points: • MRI-guided breast biopsy is performed in referral centers by an expert dedicated staff, based on prior MR imaging; contrast agent administration is usually needed for lesion targeting. • DWI represents a feasible, highly reliable technique for lesion targeting, avoiding contrast agent administration. • DWI allows a precise localization of both biopsy needle device and site marker.
MeSH term(s)	Biopsy ; Breast/diagnostic imaging ; Breast Neoplasms/diagnostic imaging ; Contrast Media ; Diffusion Magnetic Resonance Imaging ; Feasibility Studies ; Humans ; Magnetic Resonance Imaging ; Retrospective Studies ; Sensitivity and Specificity
Chemical Substances	Contrast Media
Language	English
Publishing date	2020-10-30
Publishing country	Germany
Document type	Journal Article
ZDB-ID	1085366-2
ISSN	1432-1084 ; 0938-7994 ; 1613-3749
ISSN (online)	1432-1084
ISSN	0938-7994 ; 1613-3749
DOI	10.1007/s00330-020-07396-2
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Article ; Online: What cortical areas are responsible for blindsight in hemianopic patients?

Sanchez-Lopez, Javier / Cardobi, Nicolò / Pedersini, Caterina A / Savazzi, Silvia / Marzi, Carlo A

Cortex; a journal devoted to the study of the nervous system and behavior

2020 Volume 132, Page(s) 113–134

Abstract: The presence of above-chance unconscious behavioral responses following stimulus presentation to the blind hemifield of hemianopic patients (blindsight) is a well-known phenomenon. What is still lacking is a systematic study of the neuroanatomical bases ... ...

Abstract	The presence of above-chance unconscious behavioral responses following stimulus presentation to the blind hemifield of hemianopic patients (blindsight) is a well-known phenomenon. What is still lacking is a systematic study of the neuroanatomical bases of two distinct aspects of blindsight: the unconscious above chance performance and the phenomenological aspects that may be associated. Here, we tested 17 hemianopic patients in two tasks i.e. movement and orientation discrimination of a visual grating presented to the sighted or blind hemifield. We classified patients in four groups on the basis of the presence of above chance unconscious discrimination without or with perceptual awareness reports for stimulus presentation to the blind hemifield. A fifth group was represented by patients with interruption of the Optic Radiation. In the various groups we carried out analyses of lesion extent of various cortical areas, probabilistic tractography as well as assessment of the cortical thickness of the intact hemisphere. All patients had lesions mainly, but not only, in the occipital lobe and the statistical comparison of their extent provided clues as to the critical anatomical substrate of unconscious above-chance performance and of perceptual awareness reports, respectively. In fact, the two areas that turned out to be critical for above-chance performance in the discrimination of moving versus non-moving visual stimuli were the Precuneus and the Posterior Cingulate Gyrus while for perceptual awareness reports the crucial areas were Intracalcarine, Supracalcarine, Cuneus, and the Posterior Cingulate Gyrus. Interestingly, the proportion of perceptual awareness reports was higher in patients with a spared right hemisphere. As to probabilistic tractography, all pathways examined yielded higher positive values for patients with perceptual awareness reports. Finally, the cortical thickness of the intact hemisphere was greater in patients showing above-chance performance than in those at chance. This effect is likely to be a result of neuroplastic compensatory mechanisms.
MeSH term(s)	Awareness ; Hemianopsia ; Humans ; Photic Stimulation ; Visual Cortex ; Visual Perception
Language	English
Publishing date	2020-08-26
Publishing country	Italy
Document type	Journal Article
ZDB-ID	280622-8
ISSN	1973-8102 ; 0010-9452
ISSN (online)	1973-8102
ISSN	0010-9452
DOI	10.1016/j.cortex.2020.08.007
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Article ; Online: Neural bases of unconscious orienting of attention in hemianopic patients: Hemispheric differences.

Sanchez-Lopez, Javier / Savazzi, Silvia / Pedersini, Caterina A / Cardobi, Nicolò / Marzi, Carlo A

Cortex; a journal devoted to the study of the nervous system and behavior

2020 Volume 127, Page(s) 269–289

Abstract: The aim of this research was to study the behavioral and neurophysiological correlates of visual attention orientation to unseen stimuli presented to the blind hemifield of hemianopic patients, and the existence of hemispheric differences for this kind ... ...

Abstract	The aim of this research was to study the behavioral and neurophysiological correlates of visual attention orientation to unseen stimuli presented to the blind hemifield of hemianopic patients, and the existence of hemispheric differences for this kind of unconscious attention. Behaviorally, by using a Posner paradigm, we found a significant attention effect in speed of response to unseen stimuli similar to that observed in the sighted hemifield and in healthy participants for visible stimuli. Moreover, event-related potential (ERP) and oscillatory attention-related activity were present following stimulus presentation to the blind hemifield. Importantly, in patients this pattern of activity was different as a function of the side of the brain lesion: Left damaged patients showed attention-related ERP and oscillatory activity broadly similar to that found in healthy participants. In contrast, right damaged patients showed a radically different pattern. These data confirm and extend to neurophysiological mechanisms the existence of unconscious visual orienting and are in keeping with a right hemisphere dominance for both unconscious and conscious attention.
MeSH term(s)	Consciousness ; Evoked Potentials ; Functional Laterality ; Hemianopsia ; Humans ; Orientation ; Orientation, Spatial ; Photic Stimulation ; Visual Perception
Language	English
Publishing date	2020-03-26
Publishing country	Italy
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	280622-8
ISSN	1973-8102 ; 0010-9452
ISSN (online)	1973-8102
ISSN	0010-9452
DOI	10.1016/j.cortex.2020.02.015
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In stock of ZB MED Cologne/Königswinter

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In stock of ZB MED Cologne/Königswinter

Order via subito