Gender - There is research findings pertaining to possible gender effect on recovery of functions. For example, Kimura (1983) found better recovery in females after left-hemisphere lesions than in males. This was based on the examination of 224 aphasia (impaired language ability) and apraxia (inability to perform a purposeful body movement) patients with single left hemispheric lesions. Notably speech and apraxia in females often arose from damage to anterior part of the left hemisphere rather than from the posterior region. This was not true for males. Further, progesterone is instrumental in the enhancement of neuronal outgrowth, formation of new myelin sheaths, and regulation of GABA (gama-aminobutyric acid) receptors.

Time since injury and severity - The rate of recovery is initially fastest and usually decreases over time. It has been observed that in cases of moderate to severe injury, recovery is faster during the first six months and then slower over the next two years. Thereafter, spontaneous recovery becomes slower. Severity of the injury is very important for recovery inasmuch as those with mild injuries typically recover faster as compared to those with severe injuries.