The broad goal of this clinical trial is to demonstrate whether a one-month rehabilitative training with our medical device, iReach, can promote the recovery of spatial and sensorimotor abilities and the cortical reorganization process in children with visual impairment between 3 and 36 months of age.

Development and clinical validation of a novel multisensory medical device: iReach. This device will be used for the rehabilitation and recovery of spatial and sensorimotor abilities compromised by early visual impairment (i.e., blindness or moderate to severe low vision) in children aged between 3 and 36 months. In addition to its clinical value, the investigators aim to fill a technological and methodological gap. Currently, there are no certified medical devices for early intervention, that is, systems that are intuitive, simple, and designed for rehabilitation in the early stages of development.

In detail, the goals of the current clinical trial are:

1. To verify that the number of adverse events is zero, considering reports from the attending physician;
2. To assess improvements in stationary and locomotion abilities, assessed with the Peabody Developmental Motor Scale (PDMS-2) indices;
3. To evaluate further improvements in i) reaction time (s) and frequency and accuracy of response (%) to uni- and multisensory (audio-tactile) stimulations; ii) time to reach and grasp an object (s); iii) number of attempts required to reach and grasp an object (%); iv) number of times the midline of the body is crossed to reach a lateral object (%); v) number of times an object is grasped with two hands if it is larger than the hand (%). These parameters will be extracted from video recordings;
4. To highlight changes in EEG power (dB) in the alpha band (8-12 Hz) measured in the occipital scalp area following rehabilitation with iReach.

iReach, is composed of two devices called Anchors, and a reference Tag, that can be placed either on both the body or external objects. Each Anchor measures its distance from the Tag and translates it into sensory feedback, whose intensity and time duration parameters are configurable. iReach can emit acoustic, vibrational, and RGB light stimuli, either alone or in combination, and is turned on via a button located on the external cover, which is manufactured through 3D printing.

This study is divided into two phases: usability and rehabilitation. The usability phase is aimed at defining the temporal durations of audio-tactile stimulations that will then be used in the rehabilitation phase. The patients enrolled in the iReach Device group of this phase will be involved in a one-month rehabilitation procedure (i.e., training) and will perform activities with iReach presented in the form of games that target localization, locomotion, grasping, and reaching skills. The training will be conducted both at home and at the clinical center and will be preceded and followed by two identical experimental sessions (pre- and post-training), which will monitor improvements in spatial and sensorimotor abilities following rehabilitation. Finally, an additional follow-up experimental session is planned four months after the post-training to verify whether these improvements are still present or not, both behaviorally and cortically. The participants enrolled in the Normal clinical activity group of the experimental phase will only be involved in the pre- and post-training sessions and the follow-up session without undergoing rehabilitation with iReach. The tasks the participants will have to undergo are designed for the specific age bin (i.e., 3-6 months, 6-12 months, 12-36 months)

Inclusion Criteria:

• Obtaining Informed Consent;
• Age between 3 and 36 months;
• Normal vision or visual acuity between 0 and 4.7 cy/deg, assessed using the Teller Acuity Cards;
• Absence of concurrent therapies during the experimentation;
• Adequate cognitive ability for their age, assessed using the Reynell-Zinkin, Bayley III, and/or Griffiths scales;

Exclusion Criteria:

• Children with neurological disorders or cognitive delays (assessed using the Reynell-Zinkin, Bayley III, and/or Griffiths scales);
• Children affected by other sensory disabilities in addition to visual impairment (e.g., deafness) or with motor disorders;
• Premature infants with early gestational age (< 32 weeks);
• Children with diseases affecting the central nervous system or who have experienced epileptic seizures and/or convulsions in the six months before the start of the experimentation;
• Children with tactile hypersensitivity who are taking neuroactive drugs and substances or have taken them in the six months before the start of the experimentation;
• Children with auditory and/or peripheral motor disabilities;
• Children whose parents or legal guardians have not provided informed consent;

Participant masking because the clinical trial involves infants