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Brain Areas of Time-To-Contact Perception: an Awake Surgery Study

Not Applicable
Recruiting
Conditions
Brain Tumors
Interventions
Behavioral: Behavioral task
Other: Neurological assessment
Procedure: Awake surgery
Registration Number
NCT04128306
Lead Sponsor
University Hospital, Toulouse
Brief Summary

During a brain surgery targeted to remove a brain tumor, the neurosurgeon wakes up the patient to delimit the tumor area exactly, and identify the surrounding areas, to limit the surgery damages. The present project aims at testing the patient in this awake phase to determine the brain areas implied in time to contact (TTC) perception, a function that allows determining the arrival time of moving objects and used in many tasks of our daily life.

Detailed Description

Time to contact (TTC) estimation is a major visual function that allows an observer determining the time a moving object will take to reach him. It is however striking to note that the different brain areas supporting this function are not clearly identified, in particular the contribution of non-visual areas that are engaged in the definition of a peri-personal space for the observer. This lack could be fulfilled during a brain surgery experiment. Indeed, in such a surgery, the patient is awakened, and the surgeon apply direct cortical stimulation to de-activate specific brain areas while testing different cognitive function. The failure to succeed in the task indicates that this area is engaged in the cognitive function. The present study therefore will test different brain areas to investigate their respective contribution in the TTC estimation function.

Three groups of participants will be tested, in pre and per surgery phases. After an initial pre-surgery phase, patients for which the tumor does not interfere with the TTC estimation anility will be enrolled in the Pré-Per group, and tested during the brain surgery. Patients for which the pre-test indicates that the TTC estimation is damaged by the tumor, will be tested in pre-surgery phase only, constituting the Pré-End group. Finally, a control group, paired with the patients, will be tested as well.

For the patients, all the testing phases will be achieved during their medical process. The awake surgery is now a well-established technique, currently and usually done at the University Hospital Toulouse, and the present test in the per surgery phase only lasts a couple of minutes, no more than 5 minutes. As such, there is no additional risk carried out in the project.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
240
Inclusion Criteria

For the patients:

  • Brain tumor that does not affect the dominant hand motricity. The patient that have a tumor in an area targeted for a cortical stimulation will be automatically enrolled within the Pre-End group.
  • Who will agree with all terms and sign the experimental agreement
  • Correct or corrected vision, as allowed by the surgery constraints
  • With no known oculomotor abnormalities (list of exclusion in Annexe)
  • Affiliated to a social security system

For the control group:

  • Who will agree with all terms and sign the experimental agreement
  • Correct or corrected vision
  • With no known oculomotor abnormalities.
  • Affiliated to a social security system
Exclusion Criteria

For the patients:

  • Brain tumor located in the occipital area
  • Legally protected patient, or with unknown ability to sign the experimental agreement, as determined by the medical team.
  • Medical background of neurological diseases of the central nervous system, as Parkinson, Alzheimer, stroke
  • Pregnancy

For the control group:

  • Legally protected patient, or with unknown ability to sign the experimental agreement, as determined by the medical team.
  • Medical background of neurological diseases of the central nervous system, as Parkinson, Alzheimer, stroke
  • Pregnancy

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Control groupBehavioral taskA maximum of 120 healthy matched sex and age subjects with patients will also be included
Control groupNeurological assessmentA maximum of 120 healthy matched sex and age subjects with patients will also be included
Patient groupAwake surgeryA total of 120 patients with brain tumors will be divided into our two groups, divided as follows: 1. In the group Pre-Per, 20 patients will be included by localization of electrical stimulation (60 patients in total). A patient who would be stimulable in two different areas could be included in two different groups. 2. In the group Pre-End, the subjects will be distributed by localization of the brain tumor, by lobe. A total of 20 participants will be included per lobe, corresponding to the frontal, temporal or parietal lobes (as a reminder, a tumor in the occipital lobe is an exclusion criterion), for a total of 60 participants
Patient groupBehavioral taskA total of 120 patients with brain tumors will be divided into our two groups, divided as follows: 1. In the group Pre-Per, 20 patients will be included by localization of electrical stimulation (60 patients in total). A patient who would be stimulable in two different areas could be included in two different groups. 2. In the group Pre-End, the subjects will be distributed by localization of the brain tumor, by lobe. A total of 20 participants will be included per lobe, corresponding to the frontal, temporal or parietal lobes (as a reminder, a tumor in the occipital lobe is an exclusion criterion), for a total of 60 participants
Patient groupNeurological assessmentA total of 120 patients with brain tumors will be divided into our two groups, divided as follows: 1. In the group Pre-Per, 20 patients will be included by localization of electrical stimulation (60 patients in total). A patient who would be stimulable in two different areas could be included in two different groups. 2. In the group Pre-End, the subjects will be distributed by localization of the brain tumor, by lobe. A total of 20 participants will be included per lobe, corresponding to the frontal, temporal or parietal lobes (as a reminder, a tumor in the occipital lobe is an exclusion criterion), for a total of 60 participants
Primary Outcome Measures
NameTimeMethod
Cerebral mapping61 months

Look at how the cognitive functions of perception of time before contact are attached to brain structures, their communication with other zones, their alteration due to brain tumors for patients with a brain tumor compared to control subjects. The treatment of the study being an awakened awakening as part of the routine care, there is no risk of serious adverse event.

Brain mapping will be done through neurological examinations which are questionnaires and a risk-free task. All the tasks and all the questionnaires described in the paragraph "arm and intervention" will make it possible to meet this outcome.

Secondary Outcome Measures
NameTimeMethod
Look the implication of other brain areas61 months

Look to see if brain areas other than those targeted for stimulation in awake surgery are stimulated and therefore play a role in estimating time to contact.The treatment of the study being an awakened awakening as part of the routine care, there is no risk of serious adverse event.

Other brain areas will be define through neurological examinations which are questionnaires and a risk-free task. All the tasks and the questionnaires described in the paragraph "arm and intervention" will make it possible to meet this outcome.

Trial Locations

Locations (1)

University Hospital

🇫🇷

Toulouse, France

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