Dear Users
Please note that YNiC seminars take place on an ad hoc basis over the summer holidays.
This week (YNiC open plan from 4.30 pm) there will be two internal project proposal presentations:
1) Gary Lewis
"Neuroanatomical correlates of social attitudes and personality"
2) Beth Jefferies and Glyn Hallam
"Rehabilitation of comprehension deficits after stroke"
Abstract "Direct current stimulation (tDCS) shows great promise as a method of stroke rehabilitation yet most research to date has focused on the motor domain. This project examines the remediation of multimodal comprehension impairments in aphasia using tDCS and cognitive training, building on our recent findings that such patients retain their conceptual knowledge but have difficulty shaping semantic retrieval according to the current goals or context. This motivates the use of training tasks designed to increase the flexibility of semantic processing, combined with tDCS to encourage reorganisation of brain function.
There are two phases to the project:
(i) We will explore the impact of a single session of anodal or sham tDCS on a semantic classification task (deciding which words could belong with a thematic category, such as 'picnic'). We will adjust the speed of presentation for each individual such that accuracy is around 70%, providing good sensitivity to any effects of stimulation. Before taking part, participants will have an fMRI session to acquire a full structural scan, DTI data and fMRI of a sentence listening paradigm using ISSS. This will allow us to place the electrode over structurally intact and (potentially) functioning brain tissue. In subsequent investigations, we could explore the effect of single-shot tDCS on the data fMRI (by comparing activity following sham and anodal stimulation outside the scanner) and/or compare different electrode sites (i.e., targeting perilesional tissue in left prefrontal cortex vs. functionally-connected regions in pMTG).
(ii) We then plan a larger scale tDCS study using a cross-over design to compare the effect of (i) training with anodal stimulation and (ii) training with sham. We will use a double-baseline method to ensure participants show stable performance before each intervention. The order of the interventions will be counterbalanced, and comparison between the stable baseline and sham+training will allow us to evaluate the effect of cognitive training alone, in the absence of tDCS.
This project will establish: (1) the locations and protocols for tDCS that are most effective for improving comprehension, (2) whether the positive effects of tDCS can be bolstered by concurrent cognitive training, (3) if the benefits of tDCS plus training on one task will generalise to other control-demanding tasks, (4) the duration of tDCS effects via a six-month follow-up study, and (5) the relationship between lesion location and semantic/executive control impairment, via analyses of behavioural and MRI data in a large cohort of stroke survivors. These studies will develop and evaluate an alternative therapeutic approach to comprehension deficits, with the potential to benefit many stroke survivors."
Everyone is welcome to attend and refreshments will be provided afterwards.
Best wishes Rebecca