Forgetting to remember: The impact of ecstasy/polydrug use on Prospective Memory in University students
Dr Florentia Hadjiefthyvoulou
Prof. John Fisk (UCLAN), Dr. Nikola Bridges (UCLAN), Dr. Cathy Montgomery (LJMU)
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•Everyday memory
•Cognitive failures
•Prospective memory
Real World Memory
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What is Prospective Memory (PM)?
Prospective Memory involves the remembering to carry out a particular behaviour some time in the future (Ellis, 1996)
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Classification of Prospective Memory
Prospective Memory
Storage/retention phase
Long term Short term
Retrieval phase
Time based Event based
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MDMA Neurotoxicity: Evidence from neuroimaging studies
• Ecstasy increases serotonin levels in the prefrontal cortices (Ricaurte et al., 1992)
• Serotonergic neural damage in the hippocampus (Ricaurte et al., 1992; Fischer et al., 1995; Hatzidimitriou et al., 1999)
• Serotonergic axonal loss in the frontal cortex (McCann et al., 1998)
• Frontal lobe and hippocampus are involved in memory functioning and play an important role in PM processes
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PM deficits in Ecstasy/polydrug users: Neuropsychological evidence• Heffernan et al.,(2001a;b)
• PM impairments in PMQ short-term, long-term and internally cued PM
• Effect not attributed to the use of other drugs• Fisk & Montgomery (2008)
• Cannabis-related deficits on all aspects of real world memory
• Rodgers et al., (2003) • Long-term PM deficits associated with
ecstasy • Short term PM deficits associated with
cannabis
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PM deficits in Ecstasy/polydrug users: Neuropsychological evidence
• Restricted to self-report measures
• Self-report measures limitations
-distinction of event and time based PM
-distorted self perception
• Some laboratory measures of PM– Rendell et al. (2007)
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• Self-perceptions of PM lapses–real or imagined?
• Ecstasy/polydrug-related deficits–General PM deficits or task specific?
•Distinct drug effect?
Questions from previous literature
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Everyday and Prospective Memory deficits in ecstasy/polydrug users
Rationale:
• To investigate the impact of EP use on real world memory
• Simple laboratory measures of PM to measure short/long term PM and event/time based PM
Hadjiefthyvoulou et al. (2010)
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Method
Participants:• 42 EP users• 31 non ecstasy users • University students
Measures:• A drug history questionnaire• Measures of alcohol, smoking, health and IQSelf-report measures • EMQ, CFQ, PMQ and PRMQ
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Method
Laboratory measures- PM pattern recognition test (event based PM)- PM fatigue test (time based PM/ short term PM)- Long term recall PM (long-term PM)- RBMT (2 event, 1 time based PM)
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EMQ PMQST PMQLT PMQIC Techniques CFQ PM
ecstasy/polydrugnon-ecstasy
Effect of ecstasy/polydrug use on self-report measures of real world memory
Mean values
Self-report measures
P<0.05
nsns
P<0.05
ns
P<0.05P<0.05
RBMTAppt
RBMTBel
RBMTM
es
FatigueP
M
Proce
ssingSpee
d PM
Long Ter
m PM
ecstasy/polydrugnon-ecstasy
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Effect of ecstasy/polydrug use on laboratory measures of real world memory
Laboratory measures
Mean values
ns P<.01 ns P<.05
P<.01
P<.05
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• Cannabis–Greater lifetime exposure and increased frequency of use
associated with poorer PM performance• Cocaine–Cocaine use was associated with most laboratory measures of
PM–This study is the first one to link recreational use of
cocaine with PM deficits
• Ecstasy –No aspect of ecstasy use was statistically significant as a
predictor of PM performance
Contributions of other drugs
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Further evidence for PM deficits in ecstasy/polydrug users• Hadjiefthyvoulou et al. (2011)–CAMPROMPT–3 groups–EP related deficits in event and time based PM–No significant differences in PM performance between
cannabis only users and drug naïve–Cocaine use associated with poorer event based PM–No aspect of ecstasy use was statistically significant as a
predictor of PM performance
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General Conclusions • Ecstasy/polydrug users are impaired in all aspects of
PM (not task specific)
• Cocaine is linked with PM lapses
• PM deficits are real rather than imagined
• Which drug is primarily responsible for PM deficits
• Ecstasy/polydrug use adversely effects students’ everyday functioning