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Rationale: Prospective memory (PM) deficits in recreational drug users have been documented in recent years. However the assessment of PM has largely been restricted to self report measures that fail to capture the distinction between event based and time based PM.The aim of the present study is to address this limitation.Objectives: Extending our previous research we augmented the range laboratory measures of PM by employing the CAMPROMPT test battery to investigate the impact of illicit drug use on prospective remembering in a sample of cannabis only, ecstasy/polydrug and non users of illicit drugs, separating event and time based PM performance. We also administered measures of executive function and retrospective memory in order to establish whether ecstasy/polydrug deficits in PM were mediated by group differences in these processes.Results: Ecstasy/polydrug users performed significantly worse on both event and time based prospective memory tasks in comparison to both cannabis only and non user groups.Furthermore, it was found that across the whole sample, better retrospective memory and executive functioning was associated with superior PM performance. Nevertheless, this association did not mediate the drug-related effects that were observed. Consistent with our previous study, recreational use of cocaine was linked to PM deficits.Conclusions: PM deficits have again been found among ecstasy/polydrug users which appear to be unrelated to group differences in executive function and retrospective memory.However, the possibility that these are attributable to cocaine use cannot be excluded.Prospective memory (PM) involves remembering to execute a particular behaviour at some future point in time which may be in the short or long term, for example remembering to turn off the lights when leaving a room or remembering to attend a meeting, meet a friend or pass on a message. Self report measures of this construct have been developed (e.g., Crawford et al., 2005;Hannon et al., 1995) and in previous research from our laboratory, Fisk and co-workers have demonstrated apparent impairments on these measures among ecstasy/polydrug users (Montgomery & Fisk, 2007) and cannabis only users (Fisk & Montgomery, 2008). Other researchers have also reported deficits on self report PM measures among users of illicit drugs (Heffernan et al., 2001a;2001b;Rodgers et al., 2001; and studies from our own laboratory and elsewhere have revealed deficits among illicit drug users in laboratory measures of PM (Hadjiefthyvoulou et al., in press;Rendell et al., 2007a;Rendell et al., 2009).Unsurprisingly, given their role in supporting memory functions in general, evidence suggests that PM is dependent on medial temporal-hippocampal processes. For example, in a clinical group with medial temporal sclerosis, Adda et al. (2008) found that PM performance was impaired and that among those with left hemisphere lesions the degree of impairment was correlated with that in delayed (7 day) verbal recall on the Rey Auditory Verbal Learning Task ...

The impact of ecstasy/polydrug use on real-world memory (i.e. everyday memory, cognitive failures and prospective memory [PM]) was investigated in a sample of 42 ecstasy/polydrug users and 31 non-ecstasy users. Laboratory-based PM tasks were administered along with self-reported measures of PM to test whether any ecstasy/polydrug-related impairment on the different aspects of PM was present. Self-reported measures of everyday memory and cognitive failures were also administered. Ecstasy/polydrug associated deficits were observed on both laboratory and self-reported measures of PM and everyday memory. The present study extends previous research by demonstrating that deficits in PM are real and cannot be simply attributed to self-misperceptions. The deficits observed reflect some general capacity underpinning both time- and event-based PM contexts and are not task specific. Among this group of ecstasy/polydrug users recreational use of cocaine was also prominently associated with PM deficits. Further research might explore the differential effects of individual illicit drugs on real-world memory.

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Animal models or test paradigms for predominantly female disorders, such as anxiety, often use only male animals, with little or no investigation of sex differences. Thus, this study was conducted to compare the behaviour of males and females in four widely used tests of anxiety. The behaviour of male and female Mongolian gerbils was assessed in the elevated plus maze (EPM), black-white box (BWB), open-field and social interaction tests. In the elevated plus maze, females spent proportionally less time in the centre square and greater time in the closed arms compared with males. In the black-white box, they showed significantly greater entries into the black compartment, whilst in the open field, females spent less time sniffing the arena compared with males. Thus, in these three models, there are no conclusive sex differences in anxiety-like behaviour. However, in the social interaction test, females showed more exploratory/cage-orientated behaviour and less active social and aggressive behaviour. In addition, females terminated social contact more frequently. These results can be interpreted as true sex differences, as behaviour in the open-field and social interaction tests did not differ across the oestrous cycle. In conclusion, the results show that sex differences in anxiety-like behaviour in gerbils are best detected using the social interaction test, which suggests that females show a more anxious profile. It also further highlights the need for sex differences to be investigated in tests of anxiety.