ABSTRACT
Across vertebrates, adaptive behaviors, like feeding and avoiding predators, are linked to lateralized brain function. The presence of the behavioral manifestations of these biases are associated with increased task success. Additionally, when an individual's direction of bias aligns with the majority of the population, it is linked to social advantages. However, it remains unclear if behavioral biases in humans correlate with the same advantages. This large-scale study (N = 313-1661, analyses dependent) examines whether the strength and alignment of behavioral biases associate with cognitive and social benefits respectively in humans. To remain aligned with the animal literature, we evaluate motor-sensory biases linked to motor-sequencing and emotion detection to assess lateralization. Results reveal that moderate hand lateralization is positively associated with task success and task success is, in turn, associated with language fluency, possibly representing a cascade effect. Additionally, like other vertebrates, the majority of our human sample possess a 'standard' laterality profile (right hand bias, left visual bias). A 'reversed' profile is rare by comparison, and associates higher self-reported social difficulties and increased rate of autism and/or attention deficit hyperactivity disorder. We highlight the importance of employing a comparative theoretical framing to illuminate how and why different laterization profiles associate with diverging social and cognitive phenotypes.
Subject(s)
Cognition , Functional Laterality , Humans , Cognition/physiology , Male , Female , Functional Laterality/physiology , Adult , Young Adult , Adolescent , Social Skills , Middle Aged , Emotions/physiologyABSTRACT
Hydrocephalus is a common neurological condition, the hallmark feature of which is an excess in production, or accumulation, of cerebrospinal fluid in the ventricles. Although it is associated with diffuse damage to paraventricular brain areas, patients are broadly typified by a particular pattern of cognitive impairments that include deficits in working memory, attention, and spatial abilities. There have, however, been relatively few neuropsychological accounts of the condition. Moreover, theories of the relationship between aetiology and impairment appear to have emerged in isolation of each other, and proffer fundamentally different accounts. In this primer, we aim to provide a comprehensive and contemporary overview of hydrocephalus for the neuropsychologist, covering cognitive sequelae and theoretical interpretations of their origins. We review clinical and neuropsychological assays of cognitive profiles, along with the few studies that have addressed more integrative behaviours. In particular, we explore the distinction between congenital or early-onset hydrocephalus with a normal-pressure variant that can be acquired later in life. The relationship between these two populations is a singularly interesting one in neuropsychology since it can allow for the examination of typical and atypical developmental trajectories, and their interaction with chronic and acute impairment, within the same broad neurological condition. We reflect on the ramifications of this for our subject and suggest avenues for future research.
Subject(s)
Cognitive Dysfunction , Hydrocephalus , Humans , Neuropsychological Tests , Hydrocephalus/complications , Hydrocephalus/diagnosis , Brain , Attention , Cognitive Dysfunction/complicationsABSTRACT
BACKGROUND: Cancer and its treatments have the potential to significantly impact mental health, provoking feelings of anxiety, depression, and distress, which can last long after treatment is over. One of the most rapidly emerging influences in the healthcare field is mindfulness-based interventions (MBIs), which are designed to cultivate present moment awareness, attentional flexibility, compassion and acceptance, to reduce physical and psychological distress. However, there is limited research into the efficacy of MBIs or disease specific MBIs in shifting negative coping, ruminative thinking and fears of compassion as primary outcomes in individuals with cancer. AIMS: This exploratory study was designed to evaluate inter- and intra-individual change in the management of negative coping, rumination and fears of compassion, following a cancer-specific mindfulness-based intervention. METHODS AND RESULTS: A single group, non-experimental, repeated measures study of 22 participants across six cancer care centres explored the efficacy of an 8-week Mindfulness-Based Cognitive Therapy for Cancer (MBCT-Ca) course. The Reliable Change Index (RCI) examined reliable clinical improvement, deterioration, or no change in individuals on the Mental Adjustment to Cancer Scale (MACS), the Ruminative Responses Scale (RRS) and the Fears of Compassion Scale (FCS). About 82% of participants (n = 18) saw an improvement in at least one measure. A significant decrease in primary outcome scores was observed in negative coping, ruminating and fears of self-compassion. There were significant correlations between the fear of self-compassion and depressive ruminating, fear of accepting compassion from others and showing it to others pre and post intervention. CONCLUSION: Our findings indicate that the MBCT-Ca programme may significantly reduce negative coping, ruminating and fears of self-compassion improving psychological health and wellbeing in cancer survivors.
Subject(s)
Mindfulness , Neoplasms , Self-Management , Humans , Mindfulness/methods , Empathy , Adaptation, Psychological , Fear , Neoplasms/therapyABSTRACT
BACKGROUND: Mindfulness can potentially positively impact well-being and resilience in undergraduate nursing students. The psychological well-being of such students undertaking clinical training is paramount to ensure optimal learning, and to equip them with skills to manage their wellbeing in future clinical practice. The aim of our study was to explore the views of undergraduate nursing students in relation to understanding and engaging with mindfulness, and how mindfulness could best be delivered within their university programme. METHODS: An online survey was administered via a cloud-based student response system to a convenience sample of first year undergraduate nursing students completing a Bachelor of Science (BSc) Honours (Hons) degree in nursing at a University in the United Kingdom. Data were analysed using descriptive statistics and thematic analysis. RESULTS: The survey achieved a response rate of 78% (n = 208). Seventy-nine percent of participants had heard of mindfulness and were interested in taking part in a mindfulness programme. Respondents reported that the ideal delivery of the programme would consist of weekly 45-min, in person group sessions, over a 6-week period. Respondents also indicated that a mobile application could potentially facilitate participation in the programme. Thematic analysis of open-ended comments, and free text, within the survey indicated 4 overarching themes: 1) Perceptions of what mindfulness is; 2) Previous mindfulness practice experiences; 3) Impact of mindfulness in nursing; 4) The need for a future well-being initiative for undergraduate nursing students. CONCLUSIONS: Undergraduate nursing students perceived that a mindfulness programme has the potential to enhance well-being and future clinical practice. This student cohort are familiar with mindfulness and want more integrated within their undergraduate curriculum. Further research is required to examine the effectiveness of a tailored mindfulness intervention for this population that incorporates the use of both face-to-face and mobile delivery.
ABSTRACT
BACKGROUND: Amyloid plaque and tau-containing neurofibrillary tangles are important features of Alzheimer's disease (AD). However, the relationship between these processes is still debated. OBJECTIVE: We aimed to investigate local and distant relationships between tau and amyloid deposition in the cortex in mild cognitive impairment (MCI) and AD using PET imaging. METHODS: Seventy-nine subjects (51 controls, 13 amyloid-positive MCI subjects, and 15 amyloid positive AD subjects) underwent MRI and 18F-flutemetamol PET. All MCI/AD subjects and 8 healthy controls as well as 33 healthy control subjects from the ADNI dataset also had 18F-AV1451 PET. Regional and distant correlations were examined after sampling target-to-cerebellar ratio images. Biological parametric mapping was used to evaluate voxel level correlations locally. RESULTS: We found multiple clusters of voxels with highly significant positive correlations throughout the association cortex in both MCI and AD subjects. CONCLUSION: The multiple clusters of positive correlations indicate that tau and amyloid may interact locally and be involved in disease progression. Our findings suggest that targeting both pathologies may be required.
Subject(s)
Alzheimer Disease/diagnostic imaging , Cognitive Dysfunction/diagnostic imaging , Plaque, Amyloid/diagnostic imaging , Protein Aggregates/physiology , tau Proteins , Aged , Aged, 80 and over , Alzheimer Disease/metabolism , Alzheimer Disease/psychology , Cognitive Dysfunction/metabolism , Cognitive Dysfunction/psychology , Female , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Plaque, Amyloid/metabolism , Plaque, Amyloid/psychology , Positron-Emission Tomography/methods , tau Proteins/metabolismABSTRACT
OBJECTIVE: To investigate the influence of microglial activation in the early stages of Alzheimer's disease trajectory, we assessed the relationship between microglial activation and gray matter volume and hippocampal volume in patients with mild cognitive impairment (MCI). METHODS: In this study, 55 participants (37 with early stages of MCI and 18 controls) underwent [11C]PBR28 PET, a marker of microglial activation; volumetric MRI to evaluate gray matter and hippocampal volumes as well as clinical and neuropsychometric evaluation. [11C]PBR28 VT (volume of distribution) was calculated using arterial input function and Logan graphical analysis. Gray matter volume and hippocampal volumes were calculated from MRI for each participant. Statistical parametric mapping software was used to perform voxel-wise correlations and biological parametric mapping analysis. Amyloid status was assessed using [18F]flutemetamol PET. RESULTS: Higher [11C]PBR28 VT in different cortical areas correlated with higher gray matter volume in both amyloid-positive and -negative MCI. In addition, higher hippocampal volume correlated with higher cortical [11C]PBR28 Logan VT. CONCLUSIONS: In this in vivo study, we have demonstrated that microglial activation quantified using [11C]PBR28 PET was associated with higher gray matter volume and higher hippocampal volume in patients with MCI. This might suggest that microglial activation may not always be associated with neuronal damage, and indeed it may have a beneficial effect in the early stages of the Alzheimer trajectory. While further longitudinal studies are necessary, these findings have significant implications on therapeutic strategies targeting microglial activation.
Subject(s)
Cognitive Dysfunction/diagnostic imaging , Gray Matter/diagnostic imaging , Hippocampus/diagnostic imaging , Microglia/metabolism , Aged , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/metabolism , Amyloid/metabolism , Cognitive Dysfunction/metabolism , Female , Gray Matter/metabolism , Hippocampus/metabolism , Humans , Magnetic Resonance Imaging , Male , Organ Size , Pilot Projects , Positron-Emission TomographyABSTRACT
Multisensory information typically confers neural and behavioural advantages over unisensory information. We used a simple audio-visual detection task to compare healthy young (HY), healthy older (HO) and mild-cognitive impairment (MCI) individuals. Neuropsychological tests assessed individuals' learning and memory impairments. First, we provide much-needed clarification regarding the presence of enhanced multisensory benefits in both healthily and abnormally aging individuals. The pattern of sensory dominance shifted with healthy and abnormal aging to favour a propensity of auditory-dominant behaviour (i.e., detecting sounds faster than flashes). Notably, multisensory benefits were larger only in healthy older than younger individuals who were also visually-dominant. Second, we demonstrate that the multisensory detection task offers benefits as a time- and resource-economic MCI screening tool. Receiver operating characteristic (ROC) analysis demonstrated that MCI diagnosis could be reliably achieved based on the combination of indices of multisensory integration together with indices of sensory dominance. Our findings showcase the importance of sensory profiles in determining multisensory benefits in healthy and abnormal aging. Crucially, our findings open an exciting possibility for multisensory detection tasks to be used as a cost-effective screening tool. These findings clarify relationships between multisensory and memory functions in aging, while offering new avenues for improved dementia diagnostics.
Subject(s)
Aging/pathology , Aging/physiology , Cognitive Dysfunction/diagnosis , Mass Screening/methods , Neuropsychological Tests , Acoustic Stimulation , Adult , Aged , Aged, 80 and over , Auditory Perception , Female , Humans , Male , Photic Stimulation , ROC Curve , Visual Perception , Young AdultABSTRACT
INTRODUCTION: Burn injuries are a debilitating cause of morbidity and mortality associated with the long-term impact of psychological factors on quality of life. Accurate assessment of the differential impact of burn sequelae and anxiety is often complicated by the overlap between psychological and somatic symptoms in burns patients. The Beck Anxiety Inventory (BAI) is one validated psychometric tool for anxiety assessment. The primary objective of this study is to investigate whether utilising the BAI as a tool to assess for anxiety in burns patients is biased due to the confounding of symptoms of anxiety with the physical sequelae of a burn injury. METHODS: This is a single-centre, prospective, cross-sectional study. The study was conducted in accordance with the UK Good Clinical Practice guidelines (CAPP reference number 506). Patients were recruited over a three-month period from November 2016 to February 2017 and were offered a modified BAI questionnaire to complete. Patients were asked to indicate to what degree they attributed each symptom to their physical injury or their psychological state on a visual analogue scale (VAS). RESULTS: 50 patients, comprising 33 females (66%) and 17 males (34%), participated in the study with a median age of 33.5 years (range: 20-88). Date of injury spanned May 1991 to January 2017. Percentage of the total body surface area (% TBSA) affected by burn ranged from 1 to 86%. Patients attributed eight of the 21 self-report items within the BAI as being more physical than psychological in origin. The results reveal a statistical significant difference in patient VAS scores between physical (mean: 34.16, 95% CI: 29.04-39.28) and psychological (mean: 61.2, 95% CI: 56.33-66.17) BAI items, with p<0.0001. In addition, patients with a facial burn injury were more likely to report 'face flushed' (Mann-Whitney U Test, Z=-2.11, p<0.05) and patients with a hand burn injury were more likely to report 'hands trembling' (Mann-Whitney U Test, Z=-2.52, p<0.05). CONCLUSIONS: This feasibility study found preliminary evidence suggesting that the BAI may, in part, represent misattributed symptoms of cutaneous injury from burns. However, whilst our findings suggest an attribution bias, there is not enough evidence from this data to comment on whether its use should be restricted in burns patients. Further research is needed to formally quantify convergent and divergent validity through structured interviews. In addition, further research using other self-report tools of anxiety in burns patients would be useful to corroborate the prospect of biased and confounded anxiety scores.
Subject(s)
Anxiety/psychology , Burns/psychology , Facial Injuries/psychology , Hand Injuries/psychology , Quality of Life/psychology , Adult , Aged , Aged, 80 and over , Bias , Body Surface Area , Burns/physiopathology , Cross-Sectional Studies , Facial Injuries/physiopathology , Female , Hand Injuries/physiopathology , Humans , Male , Middle Aged , Prospective Studies , Surveys and Questionnaires , Visual Analog Scale , Young AdultABSTRACT
INTRODUCTION: An investigation into long-term cognitive impairment and Quality of Life (QoL) after severe burns. METHODS: A proof of principle, cohort design, prospective, observational clinical study. Patients with severe burns (>15% TBSA) admitted to Burns ICU for invasive ventilation were recruited for psychocognitive assessment with a convenience sample of age and sex-matched controls. Participants completed psychological and QoL questionnaires, the Cogstate® electronic battery, Hopkins Verbal Learning, Verbal Fluency and Trail making tasks. RESULTS: 15 patients (11M, 4F; 41±14 years; TBSA 38.4%±18.5) and comparators (11M, 4F; 40±13 years) were recruited. Burns patients reported worse QoL (Neuro-QoL Short Form v2, patient 30.1±8.2, control 38.7±3.2, p=0.0004) and cognitive function (patient composite z-score 0.01, IQR -0.11 to 0.33, control 0.13, IQR 0.47-0.73, p=0.02). Compared to estimated premorbid FSIQ, patients dropped an equivalent of 8 IQ points (p=0.002). Cognitive function negatively correlated with burn severity (rBaux score, p=0.04). QoL strongly correlated with depressive symptoms (Rho=-0.67, p=0.009) but not cognitive function. CONCLUSIONS: Severe burns injuries are associated with a significant, global, cognitive deficit. Patients also report worse QoL, depression and post-traumatic stress. Perceived QoL from cognitive impairment was more closely associated with depression than cognitive impairment.
Subject(s)
Attention , Burns/psychology , Cognitive Dysfunction/psychology , Depression/psychology , Executive Function , Memory, Short-Term , Mental Recall , Stress Disorders, Post-Traumatic/psychology , Adult , Cognitive Dysfunction/physiopathology , Cohort Studies , Critical Care , Female , Hospitalization , Humans , Intensive Care Units , Language , Male , Mental Health , Middle Aged , Neuropsychological Tests , Patient Health Questionnaire , Proof of Concept Study , Prospective Studies , Quality of Life , Trauma Severity IndicesABSTRACT
Mortality rates alone are no longer a sufficient guide to quality of care. Due to medical advances, patients are surviving for longer following critical illness and major surgery; therefore, functional outcomes and long-term quality of life are of increasing consequence. Post-operative cognitive dysfunction has been acknowledged as a complication following anaesthesia for many years, and interest in persistent cognitive dysfunction following a critical illness is growing. Psychological and neurocognitive sequelae following discharge from intensive care are acknowledged to occur with sufficient significance to have recently coined the term 'the post-intensive care syndrome'. Rehabilitation following critical illness has been highlighted as an important goal in recently published national UK guidelines, including the need to focus on both physical and non-physical recovery. Neuropsychological and cognitive consequences following anaesthesia and critical illness are significant. The exact pathophysiological mechanisms linking delirium, cognitive dysfunction and neuropsychological symptoms following critical illness are not fully elucidated but have been studied elsewhere and are outside the scope of this article. There is limited evidence as yet for specific peri-operative preventative strategies, but early management and rehabilitation strategies following intensive care discharge are now emerging. This article aims to summarise the issues and appraise current options for management, including both neuroprotective and neurorehabilitative strategies in intensive care.
ABSTRACT
OBJECTIVE: Studying personal narratives can generate understanding of how people experience physical and mental illness. However, few studies have explored narratives of engagement in health positive behaviours, with none focusing on men specifically. Thus, we sought to examine men's experiences of their efforts to engage in and maintain healthy behaviours, focusing on meditation as an example of such behaviour. DESIGN: We recruited 30 male meditators, using principles of maximum variation sampling, and conducted two in-depth interviews with each, separated by a year. MAIN OUTCOME MEASURES: We sought to elicit men's narratives of their experiences of trying to maintain a meditation practice. RESULTS: We identified an overall theme of a 'positive health trajectory,' in particular, making 'progress' through meditation. Under this were six main accounts. Only two articulated a 'positive' message about progress: Climbing a hierarchy of practitioners, and progress catalysed in other areas of life. The other four reflected the difficulties around progress: Progress being undermined by illness; disappointment with progress; progress 'forgotten' (superseded by other concerns); and progress re-conceptualised due to other priorities. CONCLUSION: Men's narratives reveal the way they experience and construct their engagement with meditation - as an example of health behaviour - in terms of progress.
Subject(s)
Attitude to Health , Health Behavior , Meditation/psychology , Narration , Adult , Humans , Male , Middle Aged , Young AdultABSTRACT
AIMS: Nicotine is known to enhance aspects of cognitive functioning in abstinent smokers, but the effects on specific areas of executive functions and in non-smokers are inconclusive. This may be due in part to the poor sensitivity of tests used to assess executive functions. This study used a new virtual reality assessment of executive functions known as JEF (the Jansari assessment of Executive Functions) to address this issue. DESIGN: A 2 × 2 design manipulating group (smokers and never-smokers) and drug [nicotine (4 mg for smokers; 2 mg for never smokers) versus placebo gum]. SETTING: School of Psychology; University of East London. PARTICIPANTS: Seventy-two participants (aged 18-54 years): 36 minimally deprived (2 hours) smokers and 36 never-smokers. MEASUREMENTS: Components of executive function were measured using the virtual reality paradigm JEF, which assesses eight cognitive constructs simultaneously as well as providing an overall performance measure. FINDINGS: Univariate analyses of variance revealed that nicotine improved overall JEF performance, time-based prospective memory and event-based prospective memory in smokers (P < 0.01), but not in never-smokers. Action-based prospective memory was enhanced in both groups (P < 0.01) and never-smokers out-performed smokers on selective thinking and adaptive thinking (P < 0.01). CONCLUSIONS: Executive functioning and prospective memory as aspects of cognitive performance can be enhanced by nicotine gum in smokers who have abstained for as little as 2 hours.
Subject(s)
Executive Function/drug effects , Memory, Episodic , Nicotine/pharmacology , Nicotinic Agonists/pharmacology , Smoking , Thinking/drug effects , Adolescent , Adult , Female , Humans , Male , Middle Aged , Nicotine/blood , Nicotinic Agonists/blood , Young AdultABSTRACT
Traditional masculinities can mean men are unable or unwilling to deal constructively with distress. However, researchers increasingly acknowledge that men and masculinities (including hegemonic styles) are diverse. Moreover, men can positively manage their well-being, although little research explores how they do so. Uniquely, our study sought to find men who report finding ways to care for themselves to examine narratives about how such self-care originated. We aimed to do this by exploring issues underpinning men's journeys towards meditation, focusing on implications for well-being. In-depth interviews were conducted in 2009 with 30 meditators, selected using principles of maximum variation sampling, and analysed with a modified 'constant comparison' approach. Men's journeys towards meditation were fraught with difficulties. Men described crossing a threshold from boyhood into 'manhood' where they encountered traditional forms of masculinity (e.g. stoicism), and most described subsequent strategies to disconnect from emotions. While men eventually found ways to engage more constructively with their emotions and well-being, this article explores the struggle and distress of their journeys.
Subject(s)
Adaptation, Psychological , Masculinity , Meditation , Stress, Psychological/psychology , Adult , Humans , Interviews as Topic , London , Male , Men/psychology , Middle Aged , Narration , Stress, Psychological/therapy , Young AdultABSTRACT
This comprehensive, pedagogically-oriented review is aimed at a heterogeneous audience representative of the allied disciplines involved in research and patient care. After a foreword on epidemiology, genetics, and risk factors, the amyloid cascade model is introduced and the main neuropathological hallmarks are discussed. The progression of memory, language, visual processing, executive, attentional, and praxis deficits, and of behavioral symptoms is presented. After a summary on neuropsychological assessment, emerging biomarkers from cerebrospinal fluid assays, magnetic resonance imaging, nuclear medicine, and electrophysiology are discussed. Existing treatments are briefly reviewed, followed by an introduction to emerging disease-modifying therapies such as secretase modulators, inhibitors of Abeta aggregation, immunotherapy, inhibitors of tau protein phosphorylation, and delivery of nerve growth factor.
Subject(s)
Alzheimer Disease , Nootropic Agents/therapeutic use , Aged , Alzheimer Disease/diagnosis , Alzheimer Disease/drug therapy , Alzheimer Disease/physiopathology , HumansABSTRACT
OBJECTIVE: To examine, in a prospective study, the influence that temporary reversible medical castration for localized prostate cancer has on cognition, by assessing whether temporary 3-5 month treatment with a luteinizing-hormone releasing hormone (LHRH) agonist before radical radiotherapy had a short- or long-term affect on cognitive function. PATIENTS, SUBJECTS AND METHODS: Thirty-two patients with localized prostate cancer had cognitive assessments at baseline (T1) before the start of drug treatment, at 3 months (T2) or on completing drug treatment but before radiotherapy, and 9 months later (T3). Eighteen men with no prostate cancer (controls subjects) completed the cognitive tests at the same times. In addition, psychological functioning and quality of life were assessed at the same times, together with serum free and bound testosterone, beta-oestradiol and sex hormone-binding globulin levels. RESULTS: There was a significant cognitive decline (on at least one cognitive task) at T2 in 15 (47%) patients vs three (17%) of controls (odds ratio 4.412, P = 0.033). Most patients (nine of 15) who had a change in performance declined on tasks of spatial memory and ability. At T3 there was significant cognitive decline in 11 (34%) patients and five (28%) control subjects (odds ratio 1.37, P = 0.631). CONCLUSION: This pilot study suggests that short-term LHRH therapy for early-stage prostate cancer has modest short-term consequences on men's cognitive functioning; a larger prospective study is warranted.
Subject(s)
Androgen Antagonists/adverse effects , Antineoplastic Agents, Hormonal/adverse effects , Cognition Disorders/chemically induced , Cyproterone Acetate/adverse effects , Goserelin/adverse effects , Neoadjuvant Therapy/adverse effects , Prostatic Neoplasms/drug therapy , Aged , Humans , Intelligence , Male , Memory Disorders/chemically induced , Middle Aged , Pilot Projects , Prostatic Neoplasms/psychology , Quality of Life , Speech Disorders/chemically induced , Surveys and QuestionnairesABSTRACT
RATIONALE: Proficiency of information processing is likely to derive from a combination of effective processing of relevant information and efficient inhibition of unwanted or irrelevant material. Compromised inhibitory processes have been associated with the memory deficits in dementia and the elderly. These deficits in inhibition could be directly related to the reduced cholinergic function evident in dementia of the Alzheimer type (DAT). Scopolamine, a cholinergic antagonist, has been associated with disinhibition. Nicotine, a cholinergic agonist, has been associated with enhanced focus and reduced intrusions in both healthy adults and people with dementia. OBJECTIVE: This study examines the separate and combined effects of nicotine and scopolamine on inhibitory processes using retrieval induced forgetting (RIF). METHODS: In two studies, minimally deprived smokers received either nicotine or no nicotine, in the second study combined with placebo, 0.3 or 0.5 mg SC scopolamine. All volunteers completed the RIF procedure providing within-subject measures of inhibition in an episodic recall paradigm. RESULTS: Nicotine did not modulate recall of practised exemplars but it did increase inhibition of unpractised exemplars. Consistent with an effect on encoding, scopolamine reduced recall for all exemplars. Scopolamine did not differentially affect practised or unpractised exemplars, relative to the control words. CONCLUSION: Independent of its potential to influence memory at encoding, nicotine can affect task performance by inhibiting unpractised (and by implication, irrelevant) material, thereby reducing interference and benefiting the task in hand. The absence of effects of scopolamine on inhibition in the RIF paradigm argues for a more complex subdivision of "inhibitory" processes, which may be differentially influenced by cholinergic blockade.