The amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) reverses dopamine and serotonin transporters to produce efflux of dopamine and serotonin, respectively, in regions of the brain that have been implicated in reward. However, the role of serotonin/dopamine interactions in the behavioral effects of MDMA remains unclear. We previously showed that MDMA-induced locomotion,...
Objective: To examine the influence of cannabis use on long-term outcome in patients with a first psychotic episode, comparing patients who have never used cannabis with (a) those who used cannabis before the first episode but stopped using it during follow-up and (b) those who used cannabis both before the first episode and during follow-up. Methods: Patients were studied following their first...
BACKGROUND: Oral ketamine is used as an adjuvant in the treatment of refractory neuropathic and cancer-related pain. Drug interactions may alter the analgesic or other effects of ketamine. AIM AND METHODS: The aim of the study was to investigate the effect of cytochrome P450 3A enzyme inhibition with clarithromycin on the pharmacokinetics and pharmacodynamics of oral S-ketamine in a randomized...
Two studies examined correlates of the Narrative Emplotment Scale (NES), which measures the extent to which individuals perceive chance events and unchosen experiences as meaningfully connected. In Study 1 (N=99), the NES demonstrated adequate test-retest stability and good internal reliability. The scale was positively related to paranormal beliefs, mystical experiences, and absorption. In...
The relationship between attention and awareness is complex, because both concepts can be understood in different ways. Here we review our recent series of experiments which have tracked the independent contributions of different types of visual attention and awareness to electrophysiological brain responses, and then we report a new experiment focusing on spatial attention, nonspatial...
October 30, 2009O. Oshodi, O. Ikeji, S. Olotu et al.
Hospital records of patients seen between 1999 and 2002 were carefully examined. A questionnaire was used to extract relevant information from the case records and clinical diagnosis was made using the ICD-10. Cases that had evidence of pre-existing psychiatric disorder, family history of mental illness or heavy use of alcohol and/or tobacco were excluded. Out of 6,556 patients that were seen...
Freud (and later commentators) have failed to explain how the origins of psychoanalytical theory began with a positivist investment without recognizing a dual epistemological commitment: simply, Freud engaged positivism because he believed it generally equated with empiricism, which he valued, and he rejected "philosophy," and, more specifically, Kantianism, because of the associated...
Objective Several reports suggest that cannabis use is associated with an earlier age at onset of psychosis, though not all studies have operationalized cannabis use as occurring prior to onset of symptoms. This study addressed whether pre-onset cannabis use (and alcohol and tobacco use) is associated with an earlier age at onset of prodromal and psychotic symptoms. Additionally, effects of the...
People experiencing sensory deprivation often report perceptual disturbances such as hallucinations, especially over extended periods of time. However, there is little evidence concerning short-term sensory deprivation and whether its effects differ depending on the individual concerned, and in particular their proneness to psychosis. This study explored whether perceptual disturbances could be...
AbstractThe philosophy of perception currently considers how perception relates to action. Some distinctions may help, distinguishing object perception from perceptual recognition, and both from that-perception. Examples are seeing a man, recognising a man, and seeing that there is a man. Perceiving an object controls self-location by its recognising an object, which depends on memory of how it...