@phdthesis{VenturaBort2020,
  author    = {Ventura-Bort, Carlos},
  title     = {Temporo-spatial dynamics of the impact of emotional contexts on visual processing and memory},
  doi       = {10.25932/publishup-55023},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-550236},
  school      = {Universit{\"a}t Potsdam},
  pages     = {208},
  year      = {2020},
  abstract  = {It has frequently been observed that single emotional events are not only more efficiently processed, but also better remembered, and form longer-lasting memory traces than neutral material. However, when emotional information is perceived as a part of a complex event, such as in the context of or in relation to other events and/or source details, the modulatory effects of emotion are less clear. The present work aims to investigate how emotional, contextual source information modulates the initial encoding and subsequent long-term retrieval of associated neutral material (item memory) and contextual source details (contextual source memory). To do so, a two-task experiment was used, consisting of an incidental encoding task in which neutral objects were displayed over different contextual background scenes which varied in emotional content (unpleasant, pleasant, and neutral), and a delayed retrieval task (1 week), in which previously-encoded objects and new ones were presented. In a series of studies, behavioral indices (Studies 2, 3, and 5), event-related potentials (ERPs; Studies 1-4), and functional magnetic resonance imaging (Study 5) were used to investigate whether emotional contexts can rapidly tune the visual processing of associated neutral information (Study 1) and modulate long-term item memory (Study 2), how different recognition memory processes (familiarity vs. recollection) contribute to these emotion effects on item and contextual source memory (Study 3), whether the emotional effects of item memory can also be observed during spontaneous retrieval (Sstudy 4), and which brain regions underpin the modulatory effects of emotional contexts on item and contextual source memory (Study 5). In Study 1, it was observed that emotional contexts by means of emotional associative learning, can rapidly alter the processing of associated neutral information. Neutral items associated with emotional contexts (i.e. emotional associates) compared to neutral ones, showed enhanced perceptual and more elaborate processing after one single pairing, as indexed by larger amplitudes in the P100 and LPP components, respectively. Study 2 showed that emotional contexts produce longer-lasting memory effects, as evidenced by better item memory performance and larger ERP Old/New differences for emotional associates. In Study 3, a mnemonic differentiation was observed between item and contextual source memory which was modulated by emotion. Item memory was driven by familiarity, independently of emotional contexts during encoding, whereas contextual source memory was driven by recollection, and better for emotional material. As in Study 2, enhancing effects of emotional contexts for item memory were observed in ERPs associated with recollection processes. Likewise, for contextual source memory, a pronounced recollection-related ERP enhancement was observed for exclusively emotional contexts. Study 4 showed that the long-term recollection enhancement of emotional contexts on item memory can be observed even when retrieval is not explicitly attempted, as measured with ERPs, suggesting that the emotion enhancing effects on memory are not related to the task embedded during recognition, but to the motivational relevance of the triggering event. In Study 5, it was observed that enhancing effects of emotional contexts on item and contextual source memory involve stronger engagement of the brain's regions which are associated with memory recollection, including areas of the medial temporal lobe, posterior parietal cortex, and prefrontal cortex. Taken together, these findings suggest that emotional contexts rapidly modulate the initial processing of associated neutral information and the subsequent, long-term item and contextual source memories. The enhanced memory effects of emotional contexts are strongly supported by recollection rather than familiarity processes, and are shown to be triggered when retrieval is both explicitly and spontaneously attempted. These results provide new insights into the modulatory role of emotional information on the visual processing and the long-term recognition memory of complex events. The present findings are integrated into the current theoretical models and future ventures are discussed.},
  language  = {en}
}
@article{WirknerVenturaBortSchulzetal.2018,
  author    = {Wirkner, Janine and Ventura-Bort, Carlos and Schulz, Paul and Hamm, Alfons O. and Weymar, Mathias},
  title     = {Event-related potentials of emotional and neutral memories},
  series = {Psychophysiology : journal of the Society for Psychophysiological Research},
  volume    = {55},
  journal   = {Psychophysiology : journal of the Society for Psychophysiological Research},
  number    = {7},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {0048-5772},
  doi       = {10.1111/psyp.13069},
  pages     = {12},
  year      = {2018},
  abstract  = {Previous research found that memory is not only better for emotional information but also for neutral information that has been encoded in the context of an emotional event. In the present ERP study, we investigated two factors that may influence memory for neutral and emotional items: temporal proximity between emotional and neutral items during encoding, and retention interval (immediate vs. delayed). Forty-nine female participants incidentally encoded 36 unpleasant and 108 neutral pictures (36 neutral pictures preceded an unpleasant picture, 36 followed an unpleasant picture, and 36 neutral pictures were preceded and followed by neutral pictures) and participated in a recognition memory task either immediately (N=24) or 1 week (N=25) after encoding. Results showed better memory for emotional pictures relative to neutral pictures. In accordance, enhanced centroparietal old/new differences (500-900 ms) during recognition were observed for unpleasant compared to neutral pictures, most pronounced for the 1-week interval. Picture position effects, however, were only subtle. During encoding, late positive potentials for neutral pictures were slightly lower for neutral pictures following unpleasant ones, but only at trend level. To summarize, we could replicate and extend previous ERP findings showing that emotionally arousing events are better recollected than neutral events, particularly when memory is tested after longer retention intervals. Picture position during encoding, however, had only small effects on elaborative processing and no effects on memory retrieval.},
  language  = {en}
}
@article{VenturaBortWirknerWendtetal.2021,
  author    = {Ventura-Bort, Carlos and Wirkner, Janine and Wendt, Julia and Hamm, Alfons O. and Weymar, Mathias},
  title     = {Establishment of emotional memories is mediated by vagal nerve activation},
  series = {The journal of neuroscience : the official journal of the Society for Neuroscience},
  volume    = {41},
  journal   = {The journal of neuroscience : the official journal of the Society for Neuroscience},
  number    = {36},
  publisher = {Society for Neuroscience},
  address   = {Washington, DC},
  issn      = {1529-2401},
  doi       = {10.1523/JNEUROSCI.2329-20.2021},
  pages     = {7636 -- 7648},
  year      = {2021},
  abstract  = {Emotional memories are better remembered than neutral ones, but the mechanisms leading to this memory bias are not well under-stood in humans yet. Based on animal research, it is suggested that the memory-enhancing effect of emotion is based on central nor-adrenergic release, which is triggered by afferent vagal nerve activation. To test the causal link between vagus nerve activation and emotional memory in humans, we applied continuous noninvasive transcutaneous auricular vagus nerve stimulation (taVNS) during exposure to emotional arousing and neutral scenes and tested subsequent, long-term recognition memory after 1 week. We found that taVNS, compared with sham, increased recollection-based memory performance for emotional, but not neutral, material. These findings were complemented by larger recollection-related brain potentials (parietal ERP Old/New effect) during retrieval of emotional scenes encoded under taVNS, compared with sham. Furthermore, brain potentials recorded during encoding also revealed that taVNS facilitated early attentional discrimination between emotional and neutral scenes. Extending animal research, our behavioral and neu-ral findings confirm a modulatory influence of the vagus nerve in emotional memory formation in humans.},
  language  = {en}
}