procedural learning among hiv+ and hiv- individuals with substance dependence
DESCRIPTION
Procedural Learning among HIV+ and HIV- individuals with Substance Dependence. R. Gonzalez, J. Jacobus, J.W. Rodriguez, E.H. Fakhoury, E.M. Martin. Brief Background. HIV is associated with striatal damage Substance use affects striatal systems Striatum is critical for procedural learning - PowerPoint PPT PresentationTRANSCRIPT
Procedural Learning among HIV+ and HIV- individuals with Substance Dependence
R. Gonzalez, J. Jacobus, J.W. Rodriguez,
E.H. Fakhoury, E.M. Martin
Brief Background
• HIV is associated with striatal damage
• Substance use affects striatal systems
• Striatum is critical for procedural learning
• Procedural learning in HIV & substance use – A. Martin et al., (1993)– Kalechstein et al., (1998)– Van Gorp et al., (1999)– Waldrop et al., (2001)
PL Measures
Pursuit Rotor (PR)
• Trace star seeing only mirror image– Go quickly, stay inside lines
– 4 trial blocks, 2 trials each
– DV = time to complete
• Follow light around circle– 55 rpm
– 4 trial blocks, 2 20s trials each
– DV = seconds on target
Mirror Tracing (MT)
Weather Prediction (WP)
• Try to guess “sun” or “rain” based on cards – Participants are not told probability structure
– 4 trial blocks, 50 cards each
Performance on PL Tasks
Performance Indices
| General Deficit(Main Effect)
| PL Deficit(Group X Time)
| # Errors
Time (Trial Blocks)
Per
form
ance
Control Group
Clinical Group
Lea
rnin
g
Hypotheses
• HIV+ participants:– poorer performance, overall, on measures of PL
• General Deficit
– less improvement in performance over time on PL tasks• PL Deficit
• More severe substance use:– poorer performance overall and with poorer PL
• Interaction between HIV and substance use
Participants
• 79 adults with history of cocaine and/or heroin dependence– HIV- : n = 33– HIV+: n = 46
• Negative u-tox & alcohol breath test
• No cocaine or heroin use in last 7 days
• No current abuse or dependence for EtOH and other drugs
• No history of severe thought disorder or unmedicated bipolar disorder
• No history of significant loss of consciousness or neurological problems
Demographics HIV – (n = 33) HIV + (n = 46)
Age 45.8 (7.9) 44.2 (6.6) yrs of education 12.3 (1.8) 11.9 (1.7) AmNART 102.6 (9.3) 100.6 (7.6) % men 87.9% 71.7% Ethnicity/Race Caucasian 9% 2% Hispanic 3% 5% African American 88% 91% Other 0 2%
Psychiatric & Medical HIV – (n = 33) HIV + (n = 46) BDI-2 12 (10.6) 14 (12.6) STAI 38.8 (13.3) 37.7 (13.5) WURS 32.8 (19.1) 30.6 (16.6) % on psych meds 21% 36% HCV+ 30% 43% On methadone 36% 4% CD4 | 396 (206) %AIDS (CD4) | 16% plasma viral load (Md, IQR) | 399 [75, 4970] % detectable viral load | 58% on HAART | 48%
Substance Use Parameters
HIV – (n = 33) HIV + (n = 46) yrs drug use 22.5 (9.1) 22.0 (8.7) dys since last use 120 [64, 263] 182 [86, 373] History of SCID-SAM Dx Alcohol 88% 91% Cocaine 91% 96% Heroin 79% 46% Cannabis 94% 72% Stimulants 7% 24% Hallucinogens 10% 24% Sedatives 17% 29% Injection drug use 42% 46% KMSK (peak) Cocaine + Heroin M, SD 19.5 (6.2) 18 (5.6) Md, Range 19 [6, 29] 16 [9, 28] dys since peak use (Md, IQR) 1095 [240, 2980] 1095 [365, 2351]
Summary of Results
Pursuit Rotor Mirror Tracing Weather Prediction Main Effects HIV .16 < .01 .12 KMSK ns ns ns Time < .01 < .01 ns Interactions HIV x KMSK ns ns ns HIV x Time ns ns ns KMSK x Time ns .08 ns HIV x KMSK x Time .03 .01 .10
5
7
9
11
13
15
Block 1 Block 2 Block 3 Block 4
Pursuit Rotor
se
co
nd
s
HIV- HIV+
10
12
14
16
18
20
22
24
Block 1 Block 2 Block 3 Block 4
Mirror Tracing
se
co
nd
s
HIV- HIV+
Mirror Tracing HIV Main Effect: Hedges ES = 0.65, 95%CI [0.20, 1.11]Significant 3-way interactions
25
27
29
31
33
Block 1 Block 2 Block 3 Block 4
Weather Prediction
# c
orr
ec
t
HIV- HIV+
PR Interaction Effect
-4
-2
0
2
4
6
8
10
12
PR
4/4-
PR
1/1
5 10 15 20 25 30KMSKpeak-tobalcmj
-4
-2
0
2
4
6
8
10
12
PR
4/4-
PR
1/1
5 10 15 20 25 30KMSKpeak-tobalcmjKMSK KMSK
PR
ch
an
ge
PR
ch
an
ge
HIV – HIV +
n = 33 n = 46R2 = .16, p = .02 R2 = .03, p = .24
↑ improvement in PR was associated with history of ↑ severe drug use[only for HIV- subjects]
0
5
10
15
20
ST
Mt1
/4-4
/4
5 10 15 20 25 30KMSKpeak-tobalcmj
MT Interaction Effect
0
5
10
15
20
ST
Mt1
/4-4
/4
5 10 15 20 25 30KMSKpeak-tobalcmj
HIV – HIV +
n = 33 n = 46R2 = .12, p = .05 R2 = .03, p = .26
KMSK
MT
ch
an
ge
MT
ch
an
ge
↑ improvement in MT was associated with history of ↑ severe drug use [only for HIV- subjects]
KMSK
Summary• HIV+ subjects generally performed worse,
overall, on PL tasks– Significant differences on Mirror Tracing– Evidence suggests general deficit
• History of substance use severity and HIV serostatus interacted to affect procedural learning
Possible Explanations• Supersensitivity of striatal dopamine receptors
– Process disrupted by HIV
• HIV+ participants fairly “healthy”
• Control group consisted of individuals with substance dependence
• Amount of striatal damage not sufficient for functional deficits
• HIV deficits are “spotty” affecting multiple systems
Acknowledgements• NIDA
– F32 DA018522 (RG)– R01 DA12828 (EMM)
• University of Illinois Chicago, Dept. of Psychiatry
• HIV & Addictions Neuroscience– Eileen Martin, PhD– Jasmin Vassileva, PhD– Pyrai Vaughn– Elizabeth Walczak– Leslie Ladd– Sarah Wicks