Quantitative EEG Abnormalities are Associated With Memory Impairment in Recently Abstinent Methamphetamine-Dependent Individuals

Abstract

This study examined the association between brain electrical activity, measured using quantitative electroencephalography (QEEG), and performance on measures of episodic memory in a sample of nine methamphetamine-dependent individuals who were evaluated after 4 days of monitored abstinence and 10 non-drug-using comparison subjects. In methamphetamine users, but not in comparison subjects, increased theta power was correlated with poorer performance on the delayed recall subtests of the Rey Auditory Verbal Learning Test and the Rey-Osterrieth Complex Figure Test (p<0.05). There was no association between alpha, beta, and delta power and performance on the memory tests. These results complement previous findings by demonstrating that the electrophysiological abnormalities associated with methamphetamine dependence are likely to affect behavior in an observable and important manner (i.e., memory deficits) when users are not intoxicated.

The Impact of Clinical and Demographic Variables on Cognitive Performance in Methamphetamine-Dependent Individuals in Rural South Carolina

“…The demographic summary of the METH‐dependent individuals in this study is different than what is typically reported in studies of METH‐associated cognitive dysfunction, and may contribute to the differences found. For example, the average age (31.3 years) of our participants is similar to other reports (range 27.5–39.38 years) 36–41 . However, the mean number of years of education completed (11.14) is lower than what has been reported elsewhere (11.7–13.9 years) 36–40,42–49 .…”

“…However, the mean number of years of education completed (11.14) is lower than what has been reported elsewhere (11.7–13.9 years) 36–40,42–49 . In addition, although epidemiological reports indicate that at least half of METH users are female, studies examining the effects of METH on cognition typically include a lower percentage of females (23–46%) 38–42 , 50,51 . Even in studies where the gender distribution is more equitable, sex differences are rarely examined 45,47,48,52 .…”

“…Estimates of IQ are designed to test premorbid intellectual functioning and can therefore provide a gauge by which tests of more fluid cognitive functioning can be assessed. Many studies of cognitive function in METH users have assessed premorbid IQ and reported mean values ranging from 98.9 to 111.02, 36,37,39–41,43,44 however, the mean IQ of the current cohort is substantially lower at 87.28 (Fig. 1A).…”

Nicotine Administration Attenuates Methamphetamine-Induced Novel Object Recognition Deficits

“…Methamphetamine (METH) abuse is a significant public health problem with annual prevalence rate of abuse in 2013 in >1% of adolescents and young adults ( Johnston et al, 2014 ). Extensive clinical evidence indicates that METH abuse causes significant neurocognitive deficits ( Kalechstein et al, 2003 , 2009 ; Gonzalez et al, 2004 ; Hoffman et al, 2006 ; Cherner et al, 2010 ; Casaletto et al, 2014 ). For example, episodic memory is reduced among participants with a history of METH abuse (approximately 11 years), as assessed by performance in learning and recall tests ( Casaletto et al, 2014 ).…”

Electroencephalographic and Convulsive Effects of Binge Doses of (+)- Methamphetamine, 5-methoxydiisopropyltryptamine, and (±)-3,4- Methylenedioxymethamphetamine in Rats

“…The increased theta quantitative EEG power was correlated with decreased reaction times in complex tasks and diminished accuracy on the N-back working memory task [8]. Others have shown that increased theta power (slow wave) in abstinent MA users is correlated with deficits in performance on verbal and nonverbal learning and memory tests [9] and other symptoms (hypertension, elevated heart and respiratory rates, hallucinations) [1, 10]. While MA-induced seizures are typically transient, there are cases showing status epilepticus [1].…”