@phdthesis{Sixtus2018,
  author    = {Sixtus, Elena},
  title     = {Subtle fingers - tangible numbers: The influence of finger counting experience on mental number representations},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-420115},
  school      = {Universit{\"a}t Potsdam},
  pages     = {vi, 138},
  year      = {2018},
  abstract  = {Numbers are omnipresent in daily life. They vary in display format and in their meaning so that it does not seem self-evident that our brains process them more or less easily and flexibly. The present thesis addresses mental number representations in general, and specifically the impact of finger counting on mental number representations. Finger postures that result from finger counting experience are one of many ways to convey numerical information. They are, however, probably the one where the numerical content becomes most tangible. By investigating the role of fingers in adults' mental number representations the four presented studies also tested the Embodied Cognition hypothesis which predicts that bodily experience (e.g., finger counting) during concept acquisition (e.g., number concepts) stays an immanent part of these concepts. The studies focussed on different aspects of finger counting experience. First, consistency and further details of spontaneously used finger configurations were investigated when participants repeatedly produced finger postures according to specific numbers (Study 1). Furthermore, finger counting postures (Study 2), different finger configurations (Study 2 and 4), finger movements (Study 3), and tactile finger perception (Study 4) were investigated regarding their capability to affect number processing. Results indicated that active production of finger counting postures and single finger movements as well as passive perception of tactile stimulation of specific fingers co-activated associated number knowledge and facilitated responses towards corresponding magnitudes and number symbols. Overall, finger counting experience was reflected in specific effects in mental number processing of adult participants. This indicates that finger counting experience is an immanent part of mental number representations. Findings are discussed in the light of a novel model. The MASC (Model of Analogue and Symbolic Codes) combines and extends two established models of number and magnitude processing. Especially a symbolic motor code is introduced as an essential part of the model. It comprises canonical finger postures (i.e., postures that are habitually used to represent numbers) and finger-number associations. The present findings indicate that finger counting functions both as a sensorimotor magnitude and as a symbolic representational format and that it thereby directly mediates between physical and symbolic size. The implications are relevant both for basic research regarding mental number representations and for pedagogic practices regarding the effectiveness of finger counting as a means to acquire a fundamental grasp of numbers.},
  language  = {en}
}
@misc{SixtusLonnemannFischeretal.2019,
  author    = {Sixtus, Elena and Lonnemann, Jan and Fischer, Martin H. and Werner, Karsten},
  title     = {Mental Number Representations in 2D Space},
  series = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe},
  number    = {538},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-42496},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-424960},
  year      = {2019},
  abstract  = {There is evidence both for mental number representations along a horizontal mental number line with larger numbers to the right of smaller numbers (for Western cultures) and a physically grounded, vertical representation where "more is up." Few studies have compared effects in the horizontal and vertical dimension and none so far have combined both dimensions within a single paradigm where numerical magnitude was task-irrelevant and none of the dimensions was primed by a response dimension. We now investigated number representations over both dimensions, building on findings that mental representations of numbers and space co-activate each other. In a Go/No-go experiment, participants were auditorily primed with a relatively small or large number and then visually presented with quasi-randomly distributed distractor symbols and one Arabic target number (in Go trials only). Participants pressed a central button whenever they detected the target number and elsewise refrained from responding. Responses were not more efficient when small numbers were presented to the left and large numbers to the right. However, results indicated that large numbers were associated with upper space more strongly than small numbers. This suggests that in two-dimensional space when no response dimension is given, numbers are conceptually associated with vertical, but not horizontal space.},
  language  = {en}
}
@misc{FischerSixtusGoebel2015,
  author    = {Fischer, Martin H. and Sixtus, Elena and G{\"o}bel, Silke M.},
  title     = {Commentary},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {420},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-406260},
  pages     = {3},
  year      = {2015},
  abstract  = {kein Abstract vorhanden},
  language  = {en}
}