| Reference code: | PT/FB/BL-2012-089.03 |
| Location: | Arquivo PCA - Pasta 11/2012
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Title:
| Fronto-temporal network promotes verbal memory retrieval via semantic elaboration
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| Publication year: | 2014
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URL:
| http://www.google.pt/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CB8QFjAA&url=http%3A%2F%2Flup.lub.lu.se%2Frecord%2F4730112%2Ffile%2F4730118.pdf&ei=0Z4KVbuWGcW6UdKigegH&usg=AFQjCNGPh9FDC2rdgLc6BMK_awPijy49WA&sig2=t5IitZnw-LTjAG0AmFVHoA&bvm=bv.88528373,d.d24
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| Abstract/Results: | ABSTRACT:
The lexical-semantic properties of words have a significant effect on the ability to later retrieve those words. For example, processing the meaning of words, relative to processing their perceptual features, facilitates recognition. Likewise, concepts with more unique lexical-semantic features (e.g. low-frequency words) are generally better remembered than concepts with less unique features (e.g. high frequency words). Neuroimaging studies often implicate the left lateral prefrontal cortex in verbal memory retrieval. It has been argued that this activation reflects controlled semantic processing that facilitates later recognition. Yet, it remains unclear what aspects of semantic processing predict verbal memory performance and how it relates with prefrontal activation patterns. We addressed these questions in an fMRI paradigm using a verbal episodic recognition task, in which we manipulated the semantic distinctiveness of conceptual features. During encoding, participants performed a category verification task, in which they had to decide whether or not an exemplar belonged to a given category. Critically, exemplars were either typical members of a category such that they
shared many features with other members and were therefore semantically non-distinct (e.g. mammal-LION) or were atypical members of the category, bearing more unique and distinctive features (e.g. mammal-SEAL). Subsequently, participants were presented with the same exemplars among new ones, which were also typical or atypical, and had to decide whether or not the item had been presented before. Behaviorally, the recognition of atypical exemplars was more accurate than recognition of typical items. At a neural level, old items that were atypical of the category (relative to new atypical items) showed increased activation in left lateral prefrontal cortex, associated with controlled semantic elaboration, as well as bilateral middle temporal cortex, a region consistently linked to accessing semantic information.
Additionally, there was significant activation in occipitalparietal regions, including left inferior parietal lobe, left inferior occipital and bilateral angular gyrus, which may be associated with the integration of features. In contrast, old concepts that were typical members of the category (relative to new typical items) only showed occipital-parietal and anterior medial frontal activation, which might be related to source monitoring. Together, these findings reveal that processing atypical concepts improved recognition. This facilitation was accompanied by the recruitment of a left fronto-temporal network. We suggest that participants use the distinctive semantic features of atypical concepts as a cue that the concept
had been presented before. Moreover, we propose that the fronto-temporal activation is critical during verbal recognition tasks because it enables retrieval of semantic attributes that are indicative of the previously presented concepts.
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| Accessibility: | Document exists in file
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Language:
| eng
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Author:
| Ferreira, J.
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Secondary author(s):
| Frade, S., Marques, J. F., Raposo, A.
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Document type:
| Conference abstract
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Number of reproductions:
| 1
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Reference:
| Ferreira, J., Frade, S., Marques, J. F., & Raposo, A. (2014). Fronto-temporal network promotes verbal memory retrieval via semantic elaboration. In Conference proceedings of the 6th Annual Society for the Neurobiology of Language Conference (p. 89-90). Amsterdam, the Netherlands.
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| Indexed document: | No
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| Keywords: | Verbal memory / Typicality
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Fronto-temporal network promotes verbal memory retrieval via semantic elaboration Fronto-temporal network promotes verbal memory retrieval via semantic elaboration |