Introduction
Neglect Definition and Symptomatology
Sensory Neglect
Motor or Premotor Neglect
Representational (Imaginal) Neglect
Range of Space
Frame of Reference
Related Symptoms and Syndromes
Homonymous Hemianopia
Visuospatial neglect | Homonymous hemianopia | |
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Lesions | Fronto-parietal lesions (mainly territory of middle cerebral artery). | Postchiasmatic lesions of the visual tract or occipital lesions (mainly territory of posterior cerebral artery). |
Awareness for deficits | Awareness for deficits is reduced (anosognosia), contralesional parts of the body, the external and internal world seem not to exist anymore. Anosodiaphoria can occur. | Awareness for deficits can be reduced initially but improves quickly. Anosognosia and anosodiaphoria are rare. |
Modalities | Multimodal deficits can occur (visual, auditory, tactile, motor, olfactory). | Restricted to deficits of the visual modality. |
Visual behaviour | Lack of attention to contralesional hemispace, independent of gaze direction. Deviation of gaze, head and sometime upper body towards the ipsilesional side. Reduced eye contact with conversational partner. | Loss of contralesional visual field with respect to the position of the head and eyes. Compensational eye and head movements towards the contralesional hemispace. |
Drawing and cancellation | Contralesional omissions in drawing or cancellation tests. | Drawing and cancellation tests are mostly unaffected. |
Line bisection | Ipsilesional deviation. | Contralesional deviation occurs frequently. |
Attention (Posner paradigm) | Attentional shift is impaired. | Attentional shift is not impaired. |
Compensation | Cueing on the contralesional side can lead to a transient improvement. | Compensation of visual deficits with head- and eye-movements occurs spontaneously (over-compensation may occur). Cueing does not have an impact. |
Central fixation | Difficulty in maintaining central fixation. | Central fixation is not impaired. |
VEPs | Near normal response of VEPs. Prolonged latency can occur on affected side. | Different response of VEPs in ipsi- and contralesional visual field. |
Extinction | Visual extinction is commonly associated. | Visual extinction is not commonly associated. |
Extinction
Hemiparesis
Modulation of Visuospatial Neglect Symptoms by Other Cognitive Functions
The Role of Non-spatial Attention in Visuospatial Neglect
The Role of Working Memory and Executive Functions in Visuospatial Neglect
Awareness of Deficits
Theoretical and Functional-Anatomical Models
Attention-Shifting and Disengagement of Attention
Biased Body-Centered Matrix
Heilman’s and Mesulam’s Hemispatial Theory
Interhemispheric Rivalry Model
Functional-Anatomical Models
Diagnosis
Tests | Brief description | Comments and recommendations |
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Cancellation | Crossing out visual targets on a paper sheet. Omissions of contralesional targets indicates visuospatial neglect. | Good sensitivity (Marsh & Kersel, 1993). Qualitative interpretation enhances the detection rate. Starting point is most sensitive to visuospatial neglect. |
Line bisection | Marking the middle point of horizontal lines. Ipsilesional deviation indicates visuospatial neglect. | Easy and fast administration, used for screening rather than for clinical diagnosis. Good retest reliability (Facchin, Beschin, Pisano, & Reverberi, 2016). Note, that false positive results can result from HH. |
Copying figures and drawing | Copying (e.g., flower, house etc.) or drawing objects (e.g., clock). Omissions or cramming of contralesional details indicates visuospatial neglect. | Assesses mainly representational aspects of visuospatial neglect. Interpretation is limited by subjectivity. |
Reading | Reading a paragraph of text. Omissions of words or letters at the contralesional side of a line or a word indicate visuospatial neglect. | Assesses ‘Neglect dyslexia’. |
BIT (Behavioural inattention test) | Compilation of 17 subtests (such as the ones described above, and tasks related to ADL-functions). An overall index can be calculated. | Assesses functional performance. |
Catherine Bergego scale | 10-item checklist that assesses visuospatial neglect-specific behavior in ADL. | Widely used in clinical studies. |
Comb and Razor test | The patient is asked to comb their hair and shave. Omissions on contralesional side of the face indicate personal visuospatial neglect. | Used for bedside-screening rather than for clinical diagnosis. |
Eyetracking oculography | Requires the patient to focus at the midpoint of a given object, image, or task. An orientation bias towards the ipsilesional side indicates visual visuospatial neglect. | Pure assessment of visual visuospatial neglect as no manual exploration is necessary. Does not assess other aspects of visuospatial neglect. |
Test for attentional performance (TAP): subtest ‘Neglect’ | Pressing a button when a peripheral flicker stimulus appears on a screen together with distractor stimuli. Omissions on the contralesional side indicate visuospatial neglect. | If a patient suffers from HH, visuospatial neglect cannot be diagnosed with this test. |
Test for attentional performance (TAP): subtest ‘Covert Attention’ | Reacting to stimuli presented on either side of the screen preceded by a valid or invalid cue stimulus. Visuospatial neglect is indicated by reaction times in invalid trials towards the contralesional hemi-field that are even more prolonged than in healthy subjects. | Used to differentiate visuospatial neglect from visual field deficits. |
Virtual reality | Exploration of a virtual environment conveyed through a head-mounted display. The system tracks eye and head movements. | This allows the safe assessment of ADL in a virtual environment. More information on validity, reliability, or sensitivity is required. |
Clinical observation and information from relatives | Behavioural observation (e.g., during self-care, dressing, eating, or in therapeutic settings). This should also include information obtained from care-givers. | Adds important diagnostic value. |
Therapy
Types | Interventions | Brief descriptions |
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Compensation | Visual scanning | Improve scanning patterns by learning systematic search strategies using paper-pencil and large screen projections. |
Optokinetic stimulation | Induce left pursuit movement with the aid of leftward moving background targets and hereby shifting attention to the contralesional hemi-space. Can be combined with other interventions. | |
Limb activation | Improve attention toward the neglected hemifield by moving the contralesional limb in the neglected hemispace. | |
Cueing | Activate attention towards neglected side with “cueing” stimuli (visual, auditory or tactile). | |
Spatial perception | Feedback-related training of visuospatial deficits, reduction of uncertainty in space perception. | |
Neck muscle vibration | Re-center the spatial egocentric frame of reference by modifying the afferent neck proprioceptive inputs relative to the position of the head to the trunk. | |
TENS | Re-center the spatial egocentric frame of reference by transcutaneous electroneural stimulation of the left neck muscles with a low-voltage current. | |
Trunk rotation | Re-center the spatial egocentric frame of reference by modifying the afferent information relative to the position of the head to the trunk. | |
Caloric (vestibular) stimulation | Induce nystagmus towards the affected side with cold contralesional or warm ipsilesional caloric stimulation of the ear. | |
Eye patches | Increase leftward saccades by occluding the unaffected right hemifield. | |
Fresnel prisms | Shift the affected visual hemifield towards the unaffected ipsilesional egocentric frame of reference. | |
Sustained attention | Improve spatial attention by activating the arousal system (using alerting stimuli). | |
Substitution | Prism adaptation | Re-center the spatial egocentric frame of reference by using prism adaptation and successive visuo-motor actions (exploiting the after-effect of leftward shift towards the neglected hemifield). |
Diminished background pattern and foreground clutter | Minimize the required visual attention during visual scene navigation by reducing background and foreground environmental distractors. | |
Restitution | Pharmacological treatment | Improve attention by using dopaminergic, noradrenergic or pro-cholinergic drugs. |
Mental imagery | Improve representational (imagery) neglect by using visual or movement imagery. | |
VR space remapping | Remap the egocentric reference frame towards the affected hemifield by using VR systems. | |
Compensation and restitution | Feedback training | Increase patients’ self awareness (restitution) with feedback sessions (video, mirror, verbal, visuo-motor) following certain tasks, pointing out their behaviour, and teaching them “compensatory” strategies. |
TMS and tDCS | Disrupt the integrated neuronal acitvity of the intact side, dampen the attention to the ipsilesional side and thereby restore orientation balance between both hemispheres (compensation), or alternatively, induce the process of neuroplasticity (restitution). | |
Unknown | Music therapy | Stimulation via sensory and emotional pathways. |
The Role of Noninvasive Stimulation in the Treatment of Visuospatial Neglect
Studies with Animals
Studies with Healthy Subjects
Studies with Stroke Patients: Systematic Review
Search Strategy and Information Sources
Eligibility Criteria
Results
Design | Total sample/ weeks post-stroke | Stimulation site | Intensity/ current | Number of pulses per session/Duration | Number of sessions | Tpye and timing of visuospatial neglect-assessment | Main results | |
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rTMS | ||||||||
Oliveri et al. (2001) | within-subject, cross-over: Stim vs sham | n = 7 / 15.7a w (1–48)b | contralesional PPC | 115% of motor threshold | 10 pulses at 25 Hz | single session | LB; during stim | ↓ Ipsilesional bias in LB |
Brighina et al. (2003) | within-subject, uncontrolled | n = 3 / 14.6 w (12–20) | contralesional PPC | 90% of motor threshold | 900 pulses at 1 Hz | 7 sessions over 14 d | LB; 15 d before, at beginning, at end and 15 d after stim period | ↓ Ipsilesional bias in LB after stim and at FU |
Shindo et al. (2006) | within-subject, uncontrolled | n = 2 / 24 w | contralesional PPC | 95% of motor threshold | 900 pulses at 0.9 Hz | 6 sessions over 2 w | BIT; 2 w before, 1d before, 1 d after, 2 w after, 4 w after, 6 w after stim period. | ↑ BIT-scores after stim and at each FU |
Koch et al. (2008) | within -subject, uncontrolled | n = 12 / 4–24 w (no individual data provided) | contralesional PPC | 90% of motor threshold | 600 pulses at 1 Hz | single session | Naming of chimeric objects; before and after stim | ↑ Correctly named objects after stim |
Song et al. (2009) >RCT | between-subject; Stim+rehab vs rehab only | n = 14 (7 vs 7)c / 4.7 w (2–9) | contralesional PPC | 90% of motor threshold | 15 min at 0.5 Hz (450 pulses) | 28 sessions over 14 d | LB, CT; 2 w before, at the beginning, at the end, 2 w after stim period. | ↓ Ipsilesional bias in LB, ↓ omissions in CT in experimental, but not control group after stim and at FU |
Lim, Kang, and Paik (2010) | between-subject: stim+rehab vs rehab only (retrospectively selected) | n = 14 (7 vs 7) / 14.3 w (1–67) | contralesional PPC | 90% of motor threshold | 900 pulses at 1 Hz | 10 sessions over 2 w | LB, Albert test; 1 d before and 1d after stim period | ↑ Improvement in LB stim group |
Kim, Chun, Kim, and Lee (2013) >RCT | between-subject: low-frequency vs high-frequency vs sham | n = 27 (9 vs 9 vs 9) / 2.1 w (no individual data provided) | low frequency over contralesional PPC, high-frequency over ipsilesional PPC | 90% of motor threshold | -low frequency: 1200 pulses at 1 Hz -high-frequency: 1000 pulses at 10 Hz | 10 sessions over 2 w | MFVPT, LB, CT, CBS; before and after stim period. | ↑ Improvement in LB for high-fequency-stim compared to sham. |
Cha and Kim (2015a) >RCT | between-subject:Stim+rehab vs sham+rehab | n = 30 (10 vs 10 vs 10)/ 16.3 w (no individual data provided) | contralesional PPC | 90% of motor threshold | 1200 pulses at 1 Hz | 20 session over 4 w | LB, Albert test; before and after stim period. | ↑ Improvement in LB in experimental group |
Cha and Kim (2015b) >RCT | between-subject:stim+rehab vs sham+rehab | n = 20 (10 v 10)/ 4.6 w (no individual data provided) | contralesional PPC | 90% of motor threshold | 600 pulses at 1 Hz | 20 session over 4 w | MFVPT, LB, Albert Test, Star CT; before and after stim period. | ↑ Improvement in LB and MFVPT in experimental group |
Yang et al. (2015) >RCT | between-subject: low-frequency + rehab vs high-frequency + rehab vs cTBS+rehab vs sham+rehab | n = 38 (9 vs 10 vs 9 vs 10) / 14.8 w (no individual data provided) | contralesional PPC | 80% of motor threshold | -low frequency: 656 pulses at 1 Hz -high-frequency: 1000 pulses at 10 Hz -cTBS: 801 pulses (bursts of 3 pulses at 30 Hz) | 28 sessions over 4 w | CT, LB; 2 w before, at the beginning, at the end, 1 m after stim period. | ↑ CT-scores at FU for stim groups (cTBS>1 Hz > 10 Hz) compared to baseline ↓ Ipsilesional bias in LB at FU for cTBS and 1 Hz group compared to baseline |
Yang, Fong, Wp Li-Tsang, and Zhou (2016) >RCT | between-subject: stim+rehab vs stim+ cueing+rehab vs sensory cueing+rehab vs rehab only | n = 60 (20 vs 20 vs 20)/ 5.5 w (no individual data provided) | contralesional PPC | 90% of motor threshold | 900 pulses at 1 Hz | 10 sessions over 2 w | BIT, CBS; before, 2w after, 6w after stim period. | ↑ Improvement in BIT-scores for stim+cueing group compared to no stim after stim and at FU ↑ Improvement in BIT-scores for stim only group compared to no stim at FU |
spTMS | ||||||||
Oliveri et al. (1999) | within-subject, frontal vs prefrontal vs parietal stim | n = 6 / 4.4 w (4–8) | contralesional frontal, prefrontal, parietal cortex | 110% of motor threshold | single pulse | single session (45 trials) | Extinction test (sensitivity to cutaneous stim); followed by stim after 40 ms | ↓ Extinction during frontal and prefrontal stim |
cTBS | ||||||||
Nyffeler, Cazzoli, Hess, and Muri (2009) | within-subject: stim vs sham vs no intervention | n = 11 / 28.4 w (2–144) | contralesional PPC | 100% of motor threshold | 1602 (2 trains) to 2404 (4 trains) pulses (bursts of 3 pulses at 30 Hz repeated at 10 Hz) | single session | Peripheral visual attention task; before, 1, 3, 8, 24, 32, 96 h after stim. | ↑ Improvement in peripheral visual attention task for up to 8 h after 2 trains and up to 32 h after 4 trains in stim condition |
Cazzoli et al. (2012) | between-subject: stim followed by sham vs sham followed by stim vs no intervention | n = 24 (8 vs 8 vs 8) / 3.8 w (no individual data provided) | contralesional PPC | 100% of motor threshold | 2404 pulses - 4 trains (bursts of 3 pulses at 30 Hz repeated at 6 Hz) | 2 sessions over 2 d | CBS, CT, reading task, two part picture test, peripheral perception task; before, after stim and sham, 2 w after stim | ↑ Improvement in CBS-scores and peripheral perception in both stim groups compared to no-stim after stim and at FU |
Koch et al. (2012) >RCT | between-subject: stim vs sham | n = 18 (9 vs 9) / 6.2 w (4–15) | contralesional PPC | 80% of motor threshold | 1200 pulses (bursts of 3 pulses at 50 Hz, repeated at 5 Hz) | 10 session over 2 w | BIT; before, after, 4 w after stimulation period | ↑ BIT-scores for stim compared to sham after stim and at FU |
Fu et al. (2015) >RCT | between-subject:stim+rehab vs sham+rehab | n = 20 (10 vs 10)/ 6.1 w (2–16) | contralesional PPC | 80% of motor threshold | 2400 pulses – 4 trains (bursts of 3 pulses at 30 Hz, repeated at 5 Hz) | 14 sessions over 14 d | CT, LB; before, after, 4 w after stim period | ↑ CT-scores for stim compared to sham after stim ↓ Ipsilesional bias in LB for stim compared to sham at FU |
Fu et al. (2017) >RCT | between-subject: stim+visual scanning vs low-intensity stim+visual scanning | n = 12 (6 vs 6) / 5.6 w (no individual data provided) | contralesional PPC | 80% of motor threshold vs 40% of motor threshold (control condition) | 2400 pulses - 4 trains (bursts of 3 pulses at 30 Hz, repeated at 5 Hz) | 10 sessions over 10 d | CT, LB; before and after stim period. | ↓ Ipsilesional bias in LB, ↑ CT-scores for stim compared to sham after stim |
iTBS | ||||||||
Cao et al. (2016) >RCT | between-subject: stim+visual scanning vs low-intensity stim+visual scanning | n = 13 (7 vs 6)/ 4.8 w (no individual data provided) | contralesional DLPFC | 80% of motor threshold vs 40% of motor threshold (control condition) | 600 pulses – 20 short trains (bursts of 3 pulses at 50 Hz repeated at 5 Hz) | 20 sessions over 10 d | LB, CT; before and after stim period | ↑ Improvement in LB, CT in high-intensity- compared to low-intensity-group |
tDCS | ||||||||
Ko, Han, Park, Seo, and Kim (2008) | within -subject, crossover: Stim vs sham | n = 15 / 4–14 w (no individual data provided) | ipsilesional PPC (anodal) | 2.0 mA | 20 min | Single session | LB, CT; before and immediately after stim | ↑ Improvement in LB, CT in stim, but not in sham condition |
Sparing et al. (2009) | within-subject, crossover: left anodal vs left cathodal vs right anodal vs right sham stim | n = 10 / 11.6 w (no individual data provided) | ipsilesional PPC (anodal, sham), contralesional PPC (anodal, cathodal) | 1.0 mA | 10 min | Single session | TAP subtest ‘neglect’, LB; before, immediately after, 20 min after stim | ↓ Ipsilesional bias after stim in left cathodal and right anodal condition |
Sunwoo et al. (2013) | within-subject, crossover: dual (right anodal+left cathodal) vs right anodal vs sham | n = 10 / 111.2 w (4–784) | ipsilesional PPC (anodal), contralesional PPC (cathodal) | 1.0 mA | 20 min | Single session | LB, CT; before, immediately after stim | ↓ Ipsilesional bias for stim groups compared to sham (dual>anodal>sham) |
Brem, Unterburger, Speight, and Jäncke (2014) | within-subject, crossover: cognTr vs cognTr+sham vs cognTr+dual stim | n = 1 / 4 w | ipsilesional PPC (anodal), contralesional PPC (cathodal) | 1.0 mA | 20 min | Single session and 5 sessions over 5 d | TAP subtest ‘covert attention’, LB, CT, copying figures, ADL-questionnaire; before and after single stim sessions, 1 w, 3 m after stim period | ↑ Improvement in covert attention task, qualitative improvement in LB und coyping after stim compared to sham. ↑ Improvement in ADL at 3 m-FU |
Bang and Bong (2015) >RCT | between-subject: dual stim+feedback training vs feedback training | n = 12 (6 vs 6)/ 6.7 w (no individual data provided) | ipsilesional PPC (anodal), contralesional PPC (cathodal) | 1.0 mA | 20 min | 15 sessions over 3 w | MFVPT, LB; before and after stim period | ↓ Ipsilesional bias in LB, ↑ MFVPT-scores in experimental group compared to control group after stim |
Smit et al. (2015) | within-subject: dual stim vs sham | n = 5 / 230.4 w (54–592) | ipsilesional PPC (anodal), contralesional PPC (cathodal) | 2.0 mA | 20 min | 5 sessions over 5 d | LB, CT, drawing; before and after stim period | Null result |
Yi et al. (2016) >RCT | between-subject: left cathodal vs right anodal vs sham | n = 30 (10 vs 10 vs 10)/ no information provided | ipsilesional PPC (anodal), contralesional PPC (cathodal) | 2.0 mA | 30 min | 15 sessions over 3 w | MFVPT, LB, CT, CBS; before and 1 w after stim period | ↑ Improvement in MFVPT, LB, CT for both stim conditions compared to sham. No difference between stim groups |