Honors Program


Date of this Version


Document Type



Murphy, C. C. (2024). Effect of Methamphetamine Use Disorder on White Matter Integrity and Cognition. Undergraduate Honors Thesis. University of Nebraska-Lincoln.


Methamphetamine is known to cause a wide range of health effects, one of which is neuronal damage due to exposure to increased dopamine levels. Individuals who use methamphetamine have also been found to experience various impairments of cognitive functioning. I examined the relationship between cognitive impairment and fractional anisotropy, a measure of white matter impairment, within people who use methamphetamine. Regions of the brain involved in reward pathways have high concentrations of dopamine receptors, so their white matter integrity was of particular interest. Cognitive functioning was measured using two tests: the Neuro-QoL and the dimensional change card sort task. These measured everyday experiences of cognitive impairment and executive functioning and cognitive functioning, respectively. Cognitive functioning was found to be impaired in people who use methamphetamine, according to both tests. However, white matter integrity in the analyzed regions was not found to be significantly different from that of controls. White matter integrity was also not found to be correlated with cognitive functioning impairments within people who use methamphetamine. This result suggests that areas other than those studied may be more important to cognitive impairment and would be useful to study in the future. As methamphetamine use rises, understanding the connection between methamphetamine use, white matter integrity, and cognitive impairment would allow better treatments to be developed and provide added insight to the rising methamphetamine addiction crisis.