Neglect

Cognitive rehabilitation of neglect through multisensory stimulation

AvDesk is a multisensory telerehabilitation device, the result of a long-standing collaboration with IRCCS Stella Maris and the University of Bologna. For over 20 years, work has been ongoing on a compensatory rehabilitative treatment that has shown clinically significant results in subjects with both hemianopsia and neglect (unilateral spatial neglect).

By delivering temporally and spatially coincident audiovisual stimuli, AvDesk stimulates the multisensory neurons of the superior colliculus, promoting the recovery of exploration skills and gaze orientation toward the neglected hemispace.

What is neglect (unilateral spatial neglect)?

The neglect, or unilateral spatial neglect (USN), is a neuropsychological disorder characterized by the inability to orient attention, perceive stimuli, and respond to them in the hemispace contralateral to the brain lesion, in the absence of primary sensory or motor deficits that justify it.

In daily practice, a person with neglect may not eat food placed on the left half of the plate, not read the left side of a page, not shave half of their face, or bump into objects and doorframes on the neglected side. The disorder significantly compromises autonomy, personal safety, and participation in motor rehabilitation.

What are the causes of neglect?

Neglect typically occurs following lesions of the right cerebral hemisphere (particularly the posterior parietal cortex, the superior temporal gyrus, or the fronto-parietal circuits) and therefore manifests as neglect of the left hemispace. The most frequent causes are:

• stroke (ischemic or hemorrhagic) of the right hemisphere
• traumatic brain injury
• brain tumors affecting the parietal regions
• vascular malformations and aneurysms
• neurodegenerative diseases with fronto-parietal involvement

Neglect often occurs in comorbidity with hemianopsia (visual field deficit), making the clinical picture and rehabilitation even more complex.

How AvDesk supports neglect rehabilitation

The AvDesk protocol for neglect is based on the principle of multisensory integration: the patient, sitting in front of the device, maintains central fixation and must respond to stimuli presented in the neglected hemispace. Stimuli can be visual (light), auditory (sound), or bimodal (audio + visual, temporally coincident).

Bimodal stimuli particularly effectively activate the multisensory neurons of the superior colliculus, a subcortical structure that typically remains preserved even in cortical lesions that cause neglect. Repeated stimulation of these neurons exploits brain plasticity to strengthen compensatory attentional and oculomotor circuits, promoting a progressive expansion of visual exploration toward the neglected side.

The treatment is short (typically two weeks of daily sessions), non-invasive, well-tolerated, and can be delivered in a clinic or via telerehabilitation with remote monitoring by the specialist.

Clinical evidence

The effectiveness of multisensory stimulation in neglect is documented in peer-reviewed literature. Below are two reference studies published in Neuropsychological Rehabilitation:

• Multisensory stimulation for the rehabilitation of unilateral spatial neglect
  Zigiotto L. et al., Neuropsychological Rehabilitation, 2021. DOI: 10.1080/09602011.2020.1779754.
• Behavioural and functional changes in neglect after multisensory stimulation
  Làdavas E., Tosatto L., Bertini C., Neuropsychological Rehabilitation, 2020. DOI: 10.1080/09602011.2020.1786411.

For the complete scientific literature, please consult the dedicated page.