In this task, you will be given sentences in which your task is to recognize the name of the organ of the body. An organ is a collection of tissues that structurally form a functional unit specialized to perform a particular function. Although there might be several correct answers, you need to write one of them.

Example input: I have serious allergy in my left eye.
Example output: eye
Example explanation: Eye is an organ which has been affected, hence should be tagged.
Q:  In a second experiment , we use brain MRI scans of 282 subjects to demonstrate that the proposed segmentation tool is sufficiently sensitive to robustly detect hippocampal volume changes in a study of aging and Alzheimer ' s Disease .
A:
brain