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Abstract: Parkinson''s disease (PD) is associated with disturbances in sentence processing, particularly for noncanonical sentences. The present study aimed to analyse sentence processing in PD patients and healthy control participants, using a word-by-word self-paced reading task and an auditory comprehension task. Both tasks consisted of subject relative (SR) and object relative (OR) sentences, with comprehension accuracy measured for each sentence type. For the self-paced reading task, reading times (RTs) were also recorded for the non-critical and critical processing regions of each sentence. Analysis of RTs using mixed linear model statistics revealed a delayed sensitivity to the critical processing region of OR sentences in the PD group. In addition, only the PD group demonstrated significantly poorer comprehension of OR sentences compared to SR sentences during an auditory comprehension task. These results may be consistent with slower lexical retrieval in PD, and its influence on the processing of noncanonical sentences. [Copyright &y& Elsevier]

Abstract: The lexical–semantic and syntactic abilities of a group of individuals with chronic nonthalamic subcortical (NS) lesions following stroke (n =6) were investigated using the Western Aphasia Battery (WAB) picture description task [Kertesz, A. (1982). The Western aphasia battery. New York: Grune and Stratton] and compared with those of a group of subjects with Huntington''s Disease (HD) (n =6) and a nonneurologically impaired control group (n =6) matched for age, sex, and educational level. The performance of the NS and HD subjects did not differ significantly from the well controls on measures of lexical–semantic abilities. NS and HD subjects provided as much information about the target picture as control subjects, but produced fewer action information units. Analysis of syntactic abilities revealed that the HD subjects produced significantly more grammatical errors than both the NS and control subjects and that the NS group performed in a similar manner to control subjects. These findings are considered in terms of current theories of subcortical language function. Learning outcomes: As a result of this activity, the reader will obtain information about the debate surrounding the role of subcortical language mechanisms and be provided with new information on the comparative picture description abilities of individuals with known vascular and degenerative subcortical pathologies and healthy control participants. [Copyright &y& Elsevier]

There is now considerable evidence to suggest that non-demented people with Parkinson's disease (PD) experience difficulties using the morphosyntactic aspects of language. It remains unclear, however, at precisely which point in the processing of morphosyntax, these difficulties emerge. The major objective of the present study was to examine the impact of PD on the processes involved in accessing morphosyntactic information in the lexicon. Nineteen people with PD and 19 matched control subjects participated in the study which employed on-line word recognition tasks to examine morphosyntactic priming for local grammatical dependencies that occur both within (e.g. is going) and across (e.g. she gives) phrasal boundaries (Experiments 1 and 2, respectively). The control group evidenced robust morphosyntactic priming effects that were consistent with the involvement of both pre- (Experiment 1) and post-lexical (Experiment 2) processing routines. Whilst the participants with PD also recorded priming for dependencies within phrasal boundaries (Experiment 1), priming effects were observed over an abnormally brief time course. Further, in contrast to the controls, the PD group failed to record morphosyntactic priming for constructions that crossed phrasal boundaries (Experiment 2). The results demonstrate that attentionally mediated mechanisms operating at both the pre- and post-lexical stages of processing are able to contribute to morphosyntactic priming effects. In addition, the findings support the notion that, whilst people with PD are able to access morphosyntactic information in a normal manner, the time frame in which this information remains available for processing is altered. Deficits may also be experienced at the post-lexical integrational stage of processing. [ABSTRACT FROM AUTHOR]

Conflicting findings regarding the ability of people with schizophrenia to maintain and update semantic contexts have been due, arguably, to vagaries within the experimental design employed (e.g. whether strongly or remotely associated prime-target pairs have been used, what delay between the prime and the target was employed, and what proportion of related prime-target pairs appeared) or to characteristics of the participant cohort (e.g. medication status, chronicity of illness). The aim of the present study was to examine how people with schizophrenia maintain and update contextual information over an extended temporal window by using multiple primes that were either remotely associated or unrelated to the target. Fourteen participants with schizophrenia and 12 healthy matched controls were compared across two stimulus onset asynchronies (SOAs) (short and long) and two relatedness proportions (RP) (high and low) in a crossed design. Analysis of variance statistics revealed significant two- and three-way interactions between Group and SOA, Group and Condition, SOA and RP, and Group, SOA and RP. The participants with schizophrenia showed evidence of enhanced remote priming at the short SOA and low RP, combined with a reduction in the time course over which context could be maintained. There was some sensitivity to biasing contextual information at the short SOA, although the mechanism over which context served to update information appeared to be different from that in the controls. The participants with schizophrenia showed marked performance decrements at the long SOA (both low and high RP). Indices of remote priming at the short (but not the long) SOA correlated with both clinical ratings of thought disorder and with increasing length of illness. The results support and extend the hypothesis that schizophrenia is associated with concurrent increases in tonic dopamine activity and decreases in phasic dopamine activity. [Copyright &y& Elsevier]

Abstract: A central topic of discussion in the exploration of semantic disturbance in Alzheimer's disease (AD) concerns the relative contribution of semantic content (e.g., semantic features) and semantic process. Studies have suggested that semantic dysfunction in AD is the result of deficits to either semantic process, semantic content or both. Studies that have supported the loss of semantic content have been criticised for their use of verbal stimuli and cognitively challenging experimental tasks. The current study used a novel version of the yes–no recognition memory task to compare the processing of distinctive and non-distinctive features in participants with AD whilst controlling the cognitive demands of the task. The task involved five conditions which denoted the relationship between the items in the test and study phase. A ‘non-distinctive’ and a ‘distinctive’ condition were included where non-distinctive and distinctive semantic features were manipulated between study and test, respectively. Task accuracy of participants with AD decreased relative to control participants when distinctive features were manipulated between the study and test phase of the experiment. There was no significant difference between groups when non-distinctive features were manipulated. These findings provide evidence to support the loss of semantic content in AD. [Copyright &y& Elsevier]

Abstract: Background: There is a need for simple multimedia training programs designed to upskill the dementia care workforce. A DVD-based training program entitled RECAPS and MESSAGE has been designed to provide caregivers with strategies to support memory and communication in people with dementia. Objectives: The aims of this study were: (1) to evaluate the effects of the RECAPS and MESSAGE training on knowledge of support strategies, and caregiver satisfaction, in nursing home care staff, and (2) to evaluate staff opinion of the training. Design: A multi-centre controlled pretest–posttest trial was conducted between June 2009 and January 2010, with baseline, immediately post-training and 3-month follow-up assessment. Setting: Four nursing homes in Queensland, Australia. Participants: All care staff were invited to participate. Of the 68 participants who entered the study, 52 (37 training participants and 15 controls) completed outcome measures at baseline and 3-month follow-up. 63.5% of participants were nursing assistants, 25% were qualified nurses and 11.5% were recreational/activities officers. Methods: The training and control groups were compared on the following outcomes: (1) knowledge of memory and communication support strategies, and (2) caregiver satisfaction. In the training group, the immediate effects of training on knowledge, and the effects of role (nurse, nursing assistant, recreational staff) on both outcome measures, were also examined. Staff opinion of the training was assessed immediately post-training and at 3-month follow-up. Results: The training group showed a significant improvement in knowledge of support strategies from baseline to immediately post-training (p =0.001). Comparison of the training and control groups revealed a significant increase in knowledge for the training group (p =0.011), but not for the control group (p =0.33), between baseline and 3-month follow-up. Examination of caregiver satisfaction by care staff role in the training group revealed that only the qualified nurses showed higher levels of caregiver satisfaction at 3-month follow-up (p =0.013). Staff rated the training positively both for usefulness and applicability. Conclusion: The RECAPS and MESSAGE training improved nursing home care staff''s knowledge of support strategies for memory and communication, and gains were maintained at 3-month follow-up. Moreover, the training was well received by staff. [ABSTRACT FROM AUTHOR]

Abstract: Inhibitory control may be affected by Parkinson''s disease (PD) due to impairment within the non-motor basal ganglia-thalamocortical circuits. The present study aimed to identify the effects of chronic stimulation of the subthalamic nucleus (STN) on lexical-semantic inhibitory control. Eighteen participants with PD who had undergone surgery for deep brain stimulation (DBS) of the STN, completed a picture-word interference (PWI) task and the Hayling test in on and off stimulation conditions. The results of PD participants were compared with 21 non-neurologically impaired control participants. PD participants performed no differently from controls on the PWI task, and no significant differences between on and off stimulation conditions were revealed, therefore suggesting that PD participants are not impaired in lexical-semantic interference control. In contrast, in the off stimulation condition, PD participants had significantly delayed reaction times and increased errors on the inhibition section of the Hayling test compared with the STN stimulation condition and control participants. These results suggest that PD patients are impaired in aspects of inhibitory control that are dependent on behavioural inhibition (such as the suppression of prepotent responses) and selection from competing alternatives without the presence of external cues. Furthermore, STN stimulation acts to restore these behavioural inhibitory processes. [Copyright &y& Elsevier]