The Effects of Bilateral and Unilateral Perceptual-Motor Exercises on Manual Dexterity and Visuospatial Memory in Children With Nonverbal Learning Disorder

The goal of this semi-experimental study is to investigate whether bilateral (limbs of both sides of the body, such as left and right hands) perceptual-motor (PM) exercises and unilateral (limb of only one side of the body, such as only the left hand) PM exercises affect manual dexterity and visuospatial memory in children with nonverbal learning disorder (NVLD). Each type of perceptual-motor exercise (bilateral vs. unilateral) is delivered in two different ways. Within each method, free-play and non-interventional activities are scheduled at different times (e.g., at the beginning vs. the end of the intervention phase). The main questions this study aims to address are:

1. Which type of perceptual-motor (PM) exercise-bilateral or unilateral-is more effective in improving manual dexterity of left and right hands and visuospatial memory in children with nonverbal learning disorder (NVLD)?
2. Which training sequence in unilateral and bilateral groups-free-play and self-oriented activities followed by interventional exercises, or interventional exercises followed by free-play activities-has a greater impact on right and left hands manual dexterity and visuospatial memory scores in children with NVLD?

Study Overview

• Status: Completed
• Conditions: Non-verbal Learning Disorder
• Intervention / Treatment: Behavioral: Free-play activities followed by unilateral perceptual-motor (PM) training intervention; Behavioral: Unilateral perceptual-motor (PM) training intervention followed by free-play activities; Behavioral: Free play non-interventional exercises in first phase followed by bilateral interventional exercises; Behavioral: Bilateral perceptual-motor (PM) training intervention followed by free-play and non-interventional activities in Phase 2

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Iran
  • Isfahan
    • Isfahan, Isfahan, Iran, 43
      • Valiasr Girls' Primary School

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Diagnosing with Nonverbal Learning Disorder (NVLD) based on Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V)

Exclusion Criteria:

• being left-handed

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Unilateral 1 - Free play activities followed by intervention; Five participants of Unilateral main group, receive free-play and non-interventional activities during the first phase, followed by unilateral perceptual-motor exercises in the second phase of the experiment. This arm investigates the effects of Unilateral training and treatment order on manual dexterity and visuospatial memory in NVLD children.	Behavioral: Free-play activities followed by unilateral perceptual-motor (PM) training intervention; The first phase is 6sessions ( one session per week) of free-play and non-interventional activates followed by 18 sessions (three sessions per week) of interventional unilateral training program, where students have to use only their left hand for doing the assignments of protocol.
Other: Unilateral 2 - Unilateral interventional activities followed by free play; Five participants of Unilateral main group, receive unilateral interventional activities during the first phase, followed by non-interventional and free-play activities in the second phase. This arm investigates the effects of Unilateral training and treatment order on manual dexterity and visuospatial memory in NVLD children.	Behavioral: Unilateral perceptual-motor (PM) training intervention followed by free-play activities; The first 18 sessions (3 days per week) students took the unilateral (PM) exercise interventional training program, where they used only their left hand for participating in interventional training program. The second phase started after 18 sessions interventional exercises, with 6sessions (one session per week) of non-interventional , free-play, and self oriented activates.
Other: Bilateral 1 - Free play activities followed by intervention; Five participants of Bilateral main group, receive free-play and non-interventional activities during the first phase, followed by bilateral perceptual-motor exercises in the second phase of the experiment. This arm investigates the effects of Bilateral training and treatment order on manual dexterity and visuospatial memory in NVLD children.	Behavioral: Free play non-interventional exercises in first phase followed by bilateral interventional exercises; The first phase is 6sessions (one session per week) of free-play and non-interventional activates followed by 18 sessions (three sessions per week) of interventional bilateral training program, where students have to use their both hands for doing the assignments of protocol.
Other: Bilateral 2 - interventional activities followed by free play; Five participants of Bilateral main group, receive bilateral interventional activities during the first phase, followed by non-interventional and free-play activities in the second phase. This arm investigates the effects of Bilateral training and treatment order on manual dexterity and visuospatial memory in NVLD children.	Behavioral: Bilateral perceptual-motor (PM) training intervention followed by free-play and non-interventional activities in Phase 2; The first 18 sessions (three sessions per week) students took the bilateral (PM) exercise interventional training program, where they used their both hands for participating in interventional training exercises. The second phase started after 18 sessions interventional exercises, with 6sessions (one session per week) of non-interventional , free-play, and self oriented activates.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Right-hand Manual Dexterity	Pre-test scores are obtained using the Box and Blocks Test (BBT) to assess right hand manual dexterity scores before the start of the experiment. After 24 sessions, when participants have completed both the interventional and non-interventional training programs in each group (e.g., unilateral and bilateral training groups), the Box and Blocks Test (BBT) is administered again to evaluate improvements in manual dexterity scores. Comparisons of pre-test and post-test scores within each subgroup are used to assess the effects of treatment type (unilateral vs. bilateral) and treatment order (interventional exercises in the first phase vs. non-interventional activities in the first phase) on right hand manual dexterity. Scores range from 0 upward, with higher scores reflecting a greater number of blocks successfully transferred within the allotted test time using the right hand.	From enrollment to the end of treatment in each group at 12 weeks
Left-hand Manual Dexterity	Pre-test scores are obtained using the Box and Blocks Test (BBT) to assess left hand manual dexterity scores before the start of the experiment. After 24 sessions, when participants have completed both the interventional and non-interventional training programs in each group (e.g., unilateral and bilateral training groups), the BBT is administered again to evaluate improvements in manual dexterity scores. Comparisons of pre-test and post-test scores within each subgroup are used to assess the effects of treatment type (unilateral vs. bilateral) and treatment order (interventional exercises in the first phase vs. non-interventional activities in the first phase) on left hand manual dexterity. Scores range from 0 upward, with higher scores reflecting a greater number of blocks successfully transferred within the test time slot using the left hand.	From enrollment to the end of treatment at 12 weeks.
Visuospatial memory	Pre-test scores are obtained using the Chorsi Block Test (CBT) to assess visuospatial memory before the start of the experiment. After 24 sessions, when participants have completed both the interventional and non-interventional training programs in each group (e.g., unilateral and bilateral training groups), the CBT is administered again to evaluate progress in visuospatial memory. The comparison of pre-test and post-test scores within each subgroup allows assessment based on treatment type (unilateral vs. bilateral) and treatment order (interventional exercises in the first phase vs. non-interventional activities in the first phase) on visual spatial memory in NVLD children. Scores range from 0 upward, with higher scores reflecting a stronger ability to remember spatial locations and sequences of blocks presented during the test.	From enrollment to the end of treatment at 12weeks

Collaborators and Investigators

• Sponsor: Allameh Tabatabai University

Study record dates

Study Major Dates

• Study Start (Actual): May 1, 2023
• Primary Completion (Actual): July 30, 2023
• Study Completion (Actual): July 30, 2023

Study Registration Dates

• First Submitted: February 6, 2026
• First Submitted That Met QC Criteria: February 6, 2026
• First Posted (Actual): February 12, 2026

Study Record Updates

• Last Update Posted (Actual): February 17, 2026
• Last Update Submitted That Met QC Criteria: February 13, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Bilateral; Unilateral; Manual Dexterity; Perceptual-Motor exercise; Visuospatial Memory; Non-verbal Learning Disorder
• Additional Relevant MeSH Terms: Health Care Quality, Access, and Evaluation; Investigative Techniques; Epidemiologic Methods; Health Care Evaluation Mechanisms; Quality of Health Care; Public Health; Environment and Public Health; Epidemiologic Study Characteristics; Clinical Trials as Topic; Clinical Studies as Topic; Clinical Trials, Phase II as Topic
• Other Study ID Numbers: Allameh Tabataba'i University

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No