---
res:
  bibo_abstract:
  - The hippocampus is a key brain region for memory and notably for spatial memory,
    and is needed for both spatial working and reference memories. Hippocampal place
    cells selectively discharge in specific locations of the environment to form mnemonic
    represen tations of space. Several behavioral protocols have been designed to
    test spatial memory which requires the experimental subject to utilize working
    memory and reference memory. However, less is known about how these memory traces
    are presented in the hippo campus, especially considering tasks that require both
    spatial working and long -term reference memory demand. The aim of my thesis was
    to elucidate how spatial working memory, reference memory, and the combination
    of both are represented in the hippocampus. In this thesis, using a radial eight
    -arm maze, I examined how the combined demand on these memories influenced place
    cell assemblies while reference memories were partially updated by changing some
    of the reward- arms. This was contrasted with task varian ts requiring working
    or reference memories only. Reference memory update led to gradual place field
    shifts towards the rewards on the switched arms. Cells developed enhanced firing
    in passes between newly -rewarded arms as compared to those containing an unchanged
    reward. The working memory task did not show such gradual changes. Place assemblies
    on occasions replayed trajectories of the maze; at decision points the next arm
    choice was preferentially replayed in tasks needing reference memory while in
    the pure working memory task the previously visited arm was replayed. Hence trajectory
    replay only reflected the decision of the animal in tasks needing reference memory
    update. At the reward locations, in all three tasks outbound trajectories of the
    current arm were preferentially replayed, showing the animals’ next path to the
    center. At reward locations trajectories were replayed preferentially in reverse
    temporal order. Moreover, in the center reverse replay was seen in the working
    memory task but in the other tasks forward replay was seen. Hence, the direction
    of reactivation was determined by the goal locations so that part of the trajectory
    which was closer to the goal was reactivated later in an HSE while places further
    away from the goal were reactivated earlier. Altogether my work demonstrated that
    reference memory update triggers several levels of reorganization of the hippocampal
    cognitive map which are not seen in simpler working memory demand s. Moreover,
    hippocampus is likely to be involved in spatial decisions through reactivating
    planned trajectories when reference memory recall is required for such a decision.
    @eng
  bibo_authorlist:
  - foaf_Person:
      foaf_givenName: Haibing
      foaf_name: Xu, Haibing
      foaf_surname: Xu
      foaf_workInfoHomepage: http://www.librecat.org/personId=310349D0-F248-11E8-B48F-1D18A9856A87
  bibo_doi: 10.15479/AT:ISTA:th_858
  dct_date: 2017^xs_gYear
  dct_isPartOf:
  - http://id.crossref.org/issn/2663-337X
  dct_language: eng
  dct_publisher: Institute of Science and Technology Austria@
  dct_title: Reactivation of the hippocampal cognitive map in goal-directed spatial
    tasks@
...