# Interhemispheric Clusters

## Inputs

- Left Metric/Shape File A

- Left Metric/Shape File B
- Right Metric/Shape File A
- Right Metric/Shape File B
- Fiducial Coordinate File
- Open Topology File
- Area Correction Metric/Shape File
- Area Correction Metric/Shape File Column
- Cluster Negative Threshold
- Cluster Positive Threshold
- Left/Right Shuffled T-Map Iterations
- Shuffled T-Map Iterations
- P-Value (typically 0.05)

- Option to compute Degrees-of-Freedom
- Option to compute P-Value

## Outputs

- Left T-Map Metric/Shape File
- Left Shuffled T-Map Metric/Shape File
- Right T-Map Metric/Shape File
- Right Shuffled T-Map Metric/Shape File
- T-Map Metric/Shape File
- Shuffled T-Map Metric/Shape File
- Paint File showing clusters.
- Text Report of clusters

## Algorithm

- Create the T-Map for the left hemisphere
metric/shape files A & B.
- Create the T-Map for the right
hemisphere metric/shape files A & B.
- Create the T-Map metric/shape file which contains one column that
is the product of the T-Values from the left and right T-Map files.
- Create the left shuffled
T-Map file.
- Create the right shuffled
T-Map file.
- Create the Shuffled T-Map metric/shape file which contains
"shuffled T-Map iterations" columns where each column is the product of
a randomly selected column from the left and right shuffled T-Map files.
- Search for clusters in the T-Map metric/shape file.
- Search for clusters in the Shuffled T-Map metric/shape file.
- In the shuffled T-Map clusters, find the area of the the
"P-Value" largest cluster. For example, if there are 100
iterations in the shuffled T-Map file and the P-Value is 0.05, use the
area from the 5th largest cluster.
- Determine the P-Value for each of the T-Map clusters by finding
its rank in the Shuffled T-Map file. For example, if the area of
a T-Map cluster is between the 7th and 8th largest Shuffled T-Map
clusters and there are 100 Shuffled T-Map clusters, the T-Map cluster's
p-value is 0.07.
- Create the text report.
- Create the Paint File showing the significant T-Map clusters.