A Program of Research Examining the Cognitive Correlates of Methamphetamine Abuse.

Cognitive Battery Broad in Scope Probes Simple Effects –or Uses Instruments Known to Tap Specific Effects

__________________________ Several Studies N’s will be reported Comparison Groups do not differ in: –Age –Gender –Education –Ethnicity

Memory Tests Word Recall Picture Recall Word Recognition Picture Recognition Backward Digit Span

Perceptual Speed and Manipulation of Information Digit Symbol Trail Making A Trail Making B

Other Instruments Ability to Ignore Irrelevant Information Stroop Short Form IQ Shipley-Hartford Vocabulary Shipley-Hartford Abstract Thinking Verbal Fluency FAS Abstract Reasoning WCST

First Question Are there cognitive deficits in individuals currently abusing methamphetamine?

Perceptual Speed and Manipulation of Information N= 65 per group * *

Ability to Ignore Irrelevant Information - Stroop Test N = 65 per group *

Memory Tests N = 65 per group * *

Short Form IQ N= 65 per group *

Other Measures Verbal Fluency FASNS Working Memory for Digits Backward SpanNS Abstract Thinking WCSTNS

Second Question Are the deficits found in current methamphetamine abusers associated with the amount, pattern, frequency or length of use?

Associations with Cognitive Deficits N = 90 MA Abusers No Association was found for Length of Use Age Family History Medical History Gender Route of Administration

Association with Cognitive Deficits N = 90 MA Abusers Frequency of Use Predicts: –Recallp=.02 –Recognitionp=.02 –Wordp=.01 –Picturep=.02 –Stroop Interferencep<.01 –Digit Symbolp=.02

Third Question Are the same deficits found for current abuse of other stimulants such as cocaine?

Comparison of Cognitive Performance of Current Abusers of MA and Cocaine N = 160 Four groups of 40 MA MA comparison Cocaine Cocaine comparison

MA vs. Cocaine MeasureMA Comp Coc. Comp Vocabulary26.630*24.728* Abstract Thinking11.516** * Digit Symbol5366**5156 Trails A3227**3631 Trails B8162**8770 Stroop CW3946** * Word Recall3.16.2*2.54.2** Picture Recall **

Difference on Word Recognition for groups with Wender Scores >46 & <46 Mean Word Recognition WURS> WURS<4615.2(t 80 =2.04, p=.04)

Effect of Childhood ADHD as Measured by the Wender Utah Rating Scale WURS Score does not predict cognitive performance. WURS Score >46 = Probable ADHD 83 Currently Using MA Abusers were divided into two groups: >46 (N=25) and > 46 (N=58).

Differences on WCST between Probable ADHD and Comparison Groups >46 Comparison Categories * Total Errors * Perseverative * Nonperseverative * % Conceptual Level * Failure to Maintain Set * <46 vs. Comparison NS on all Measures

Fourth Question What is the duration of the deficits after use stops?

Memory Months N=22

Ability to Ignore Irrelevant Information Months Cross Sectional Data

Manipulation of Information and Perceptual Speed Months N = 7

Memory Months N=7

Manipulation of Information and Perceptual Speed Months Cross Sectional Data

Manipulation of Information and Perceptual Speed N = 22

Memory Months Cross Sectional Data

Work Planned and in Progress: Further Questions

Questions about Memory Is the problem for abusers task difficulty or verbal material? Does the problem exist for Semantic as well as Episodic Memory? Is Implicit Memory Effected? Is Working Memory Effected?

Questions about Memory Continued What memory process(s) are affected? –Encoding –Rehearsal –Retrieval

Does the problem exist for Semantic as well as Episodic Memory? No We found no difference between MA abusers and the comparison group on Shipley-Hartford Vocabulary and FAS. Both of these are tests of Semantic Memory.

Is Implicit Memory Effected? Preliminary analyses suggest that Implicit Memory is not affected in MA abusers. MA Comparison Word Fragment Words Total Words N (MA=17, Comparison=14)

Is Working Memory Effected? Results from our tests of working memory are not consistent. MA Comparison Missing Digit Sentence Span1.92.4* N ( MA=17, Comparison=14 )

Questions About Attention How pervasive are problems with attention? If attention is a problem, how long does the problem last? Do deficits in attention account for some of the problems with memory?

Questions about Executive Function Are there deficits found on tasks that are associated with a specific area of the prefrontal cortex? Is the score on the measure of childhood ADHD associated with performance on tasks tapping executive function?

Word Recognition

Word Recall