Sensori-motor and Perceptual Functions of the PPC.

Sensori-motor and Perceptual Functions of the Posterior Parietal Cortex (PPC) in Patients With Optic Ataxia (AO) and Healthy Subjects.

Status

Recruiting

Phases

Unknown

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT03286686

Acronym

PPCfonctions

Enrollment

160

Registered

2017-09-18

Start date

2018-02-22

Completion date

2031-02-22

Last updated

2026-01-20

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy Volunteers, Optic Ataxia

Keywords

optic ataxia, posterior parietal cortex functions, multisensory integration

Brief summary

To produce hand's movement directed towards a target, the investigator must combine several sensory information, such as vision or proprioception. The posterior parietal cortex (PPC) is a region of the cortex involved in this multisensory integration. A lesion of the PPC cause a visuo-motor trouble called optic ataxia but these patients also have perceptual troubles. The aim of the study is to understand the different functions of the PPC and especially how the processes of spatial coding of the sensory information influences perception and motor planning. In this study, the investigator want to explore the sensory motor and the perceptual performance of patients with optic ataxia compared with healthy subjects, using 6 behavioral tests. Objectify the consequences of PPC impairment (visual-motor and perceptual consequences) on patients' quality of life and autonomy.

Interventions

BEHAVIORALpoint targets

In the experiences 1 and 2, the participant needs to point different visual targets (LED) in the dark.

BEHAVIORALtactile stimulation

In the experience 3, a tactile stimulation is applied to the middle finger of the 2 hands. The participant needs to indicate into a microphone when he feels the stimulation.

BEHAVIORALvisual images

Target dots or visual images are presented on a computer screen. The participant is required to point to the targets or to react as soon as possible by pressing a response button when they are detected.

Study design

Allocation

NON_RANDOMIZED

Intervention model

PARALLEL

Primary purpose

BASIC_SCIENCE

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

18 Years to 75 Years

Healthy volunteers

Yes

Inclusion criteria

All patients and healthy subjects: * male and female, age from 18 to 75 years included * normal vision or corrected vision * covered by social security * signed written informed consent Patients: * neurological injury in posterior parietal cortex supported by a cerebral MRI * present optic ataxia symptoms Healthy subjects * no known neurological injury

Exclusion criteria

\- unable to comply with the tasks (neurological, psychiatric, sensory or motor troubles)

Design outcomes

Primary

Measure	Time frame
response error - number of pointing error	Day 0 after each stimulation
response error -measure of reaction times	Day 0 after each stimulation
response error - percentage of right responses	Day 0 after each stimulation

Countries

France

Contacts

CONTACTLaure PISELLA, PhD

laure.pisella@inserm.fr4 72 91 34 05

PRINCIPAL_INVESTIGATORLaure PISELLA, PhD

INSERM U1028 - Impact - CRNL

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026