Interruption of Dorsal Visual Stream Using TMS

Interruption of Dorsal Visual Stream Using TMS in Normal Controls

Trans Cranial Magnetic Stimulation (TMS) over dorsal visual system will disturb the ability to identify objects with decreased level of fragmentation

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Device: No TMS intervention; Device: TMS over the PO3 EEG site; Device: TMS over the vertex

Detailed Description

The participants performed two tasks under three different TMS conditions: no TMS, 10Hz TMS for over the dorsal stream (PO3 EEG site) or over the vertex.

First they performed a perceptual closure task which asked them to identify an object in a series of six progressively less degraded pictures.

Then, they also performed a control task previously shown not to be mediated by the LOC and not to be impaired in schizophrenia: The perception of illusory contours.

• Study Type: Interventional
• Enrollment (Actual): 12
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Israel
  • Tel-hashomer, Israel, 52621
    • Psychiatry Clinic - Sheba Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Normal controls

Exclusion Criteria:

• neurological, ophthalmological or psychiatric problems
• family history of schizophrenia
• left handed

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Randomized
• Interventional Model: Single Group Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: No TMS stimulation; The patients performed 2 tasks: a study and a control assignments with no TMS stimulation.	Device: No TMS intervention; In the "no TMS" condition, no simulation was given and no coil placed near participants' heads.
Experimental: TMS over the dorsal stream; The patients performed 2 tasks: a study and a control assignments under TMS stimulation over the dorsal stream area (PO3 EEG site).	Device: TMS over the PO3 EEG site; 10Hz TMS over the dorsal stream (PO3 EEG site); Other Names: MAGSTIM biphasic stimulator
Sham Comparator: TMS over the vertex; The patients performed 2 tasks: a study and a control assignments under TMS stimulation over the vertex area.	Device: TMS over the vertex; 10Hz TMS for over vertex.; Other Names: MAGSTIM biphasic stimulator

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Results of the study assignments performed by the participants during the study.	The subjects performed 2 tasks: The primary dependent measures consisted of the level of detail needed for correct object identification, response accuracy, and response time in milliseconds for correct responses. Illusory Contour Task: Subjects also performed a pulsed pedestal task, Participants were shown 55 drawings for 500 ms each. Some drawings contained partial contours which defined a geometric shape, while in others the contours did not define a shape. Participants were asked to indicate whether they recognized a geometric shape or not. Accuracy and response time were measured.	The participants performed the tasks once during their study visit

Collaborators and Investigators

• Sponsor: Sheba Medical Center
• Investigators: Principal Investigator: Revital Amiaz, MD, Sheba Medical Center

Study record dates

Study Major Dates

• Study Start: January 1, 2006
• Primary Completion (Actual): July 1, 2010

Study Registration Dates

• First Submitted: January 4, 2007
• First Submitted That Met QC Criteria: January 4, 2007
• First Posted (Estimate): January 5, 2007

Study Record Updates

• Last Update Posted (Estimate): August 4, 2011
• Last Update Submitted That Met QC Criteria: August 3, 2011
• Last Verified: August 1, 2011

More Information

Terms related to this study

• Keywords: Normal Controls
• Other Study ID Numbers: SHEBA-06-4252-RA-CTIL