@article{ZakariasSalisWartenburger2018,
  author    = {Zakarias, Lilla and Salis, Christos and Wartenburger, Isabell},
  title     = {Transfer effects on spoken sentence comprehension and functional communication after working memory training in stroke aphasia},
  series = {Journal of neurolinguistics : an international journal for the study of brain function in language behavior and experience},
  volume    = {48},
  journal   = {Journal of neurolinguistics : an international journal for the study of brain function in language behavior and experience},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0911-6044},
  doi       = {10.1016/j.jneuroling.2017.12.002},
  pages     = {47 -- 63},
  year      = {2018},
  abstract  = {Recent treatment protocols have been successful in improving working memory (WM) in individuals with aphasia. However, the evidence to date is small and the extent to which improvements in trained tasks of WM transfer to untrained memory tasks, spoken sentence comprehension, and functional communication is yet poorly understood. To address these issues, we conducted a multiple baseline study with three German-speaking individuals with chronic post stroke aphasia. Participants practised two computerised WM tasks (n-back with pictures and aback with spoken words) four times a week for a month, targeting two WM processes: updating WM representations and resolving interference. All participants showed improvement on at least one measure of spoken sentence comprehension and everyday memory activities. Two of them showed improvement also on measures of WM and functional communication. Our results suggest that WM can be improved through computerised training in chronic aphasia and this can transfer to spoken sentence comprehension and functional communication in some individuals.},
  language  = {en}
}
@article{MaetzigVasishthEngelmannetal.2018,
  author    = {M{\"a}tzig, Paul and Vasishth, Shravan and Engelmann, Felix and Caplan, David and Burchert, Frank},
  title     = {A computational investigation of sources of variability in sentence comprehension difficulty in aphasia},
  series = {Topics in cognitive science},
  volume    = {10},
  journal   = {Topics in cognitive science},
  number    = {1},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {1756-8757},
  doi       = {10.1111/tops.12323},
  pages     = {161 -- 174},
  year      = {2018},
  abstract  = {We present a computational evaluation of three hypotheses about sources of deficit in sentence comprehension in aphasia: slowed processing, intermittent deficiency, and resource reduction. The ACT-R based Lewis and Vasishth (2005) model is used to implement these three proposals. Slowed processing is implemented as slowed execution time of parse steps; intermittent deficiency as increased random noise in activation of elements in memory; and resource reduction as reduced spreading activation. As data, we considered subject vs. object relative sentences, presented in a self-paced listening modality to 56 individuals with aphasia (IWA) and 46 matched controls. The participants heard the sentences and carried out a picture verification task to decide on an interpretation of the sentence. These response accuracies are used to identify the best parameters (for each participant) that correspond to the three hypotheses mentioned above. We show that controls have more tightly clustered (less variable) parameter values than IWA; specifically, compared to controls, among IWA there are more individuals with slow parsing times, high noise, and low spreading activation. We find that (a) individual IWA show differential amounts of deficit along the three dimensions of slowed processing, intermittent deficiency, and resource reduction, (b) overall, there is evidence for all three sources of deficit playing a role, and (c) IWA have a more variable range of parameter values than controls. An important implication is that it may be meaningless to talk about sources of deficit with respect to an abstract verage IWA; the focus should be on the individual's differential degrees of deficit along different dimensions, and on understanding the causes of variability in deficit between participants.},
  language  = {en}
}