Prior to the release of ImageJ in 1997, a similar freeware image analysis program known as NIH Image had been developed for Macintosh computers running pre-Mac OS X operating systems.

A contour was then traced around the perimeter of the crushed region, as assessed by its increased optical density, using the polygon tool provided by NIH Image.

The recorded images were analyzed using NIH Image 1.61 software (available via download at http:rsb.info.nih.gov/nih-image).

Confocal stacks were projected and then imported into NIH Image 1.6 software (freeware at http://rsb.info.nih.gov/nih-image/).

Where can I find information about NIH Image (the software package)?

NIH Image is a public domain image processing and analysis program for the Macintosh.

Signal intensities of protein bands were quantified with NIH Image 1.62.

Signal intensities were quantified with ImageQuant software (Molecular Dynamics) or NIH Image 1.62.

The orientation of the tract was measured by drawing a line parallel to its edges and measuring the angle of this line using NIH Image 1.60 software.

Neurite length was assessed by tracing the neurite using the straight-line tool in NIH Image.