Article

Brain activation and lexical learning: the impact of learning phase and word type.

Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal, Montréal, Canada.
NeuroImage (Impact Factor: 6.13). 10/2009; 49(3):2850-61. DOI: 10.1016/j.neuroimage.2009.10.007
Source: PubMed

ABSTRACT This study investigated the neural correlates of second-language lexical acquisition in terms of learning phase and word type. Ten French-speaking participants learned 80 Spanish words-40 cognates, 40 non-cognates-by means of a computer program. The learning process included the early learning phase, which comprised 5 days, and the consolidation phase, which lasted 2 weeks. After each phase, participants performed an overt naming task during an er-fMRI scan. Naming accuracy was better for cognates during the early learning phase only. However, cognates were named faster than non-cognates during both phases. The early learning phase was characterized by activations in the left iFG and Broca's area, which were associated with effortful lexical retrieval and phonological processing, respectively. Further, the activation in the left ACC and DLPFC suggested that monitoring may be involved during the early phases of lexical learning. During the consolidation phase, the activation in the left premotor cortex, the right supramarginal gyrus and the cerebellum indicated that articulatory planning may contribute to the consolidation of second-language phonetic representations. No dissociation between word type and learning phase could be supported. However, a Fisher r-to-z test showed that successful cognate retrieval was associated with activations in Broca's area, which could reflect the adaptation of known L1 phonological sequences. Moreover, successful retrieval of non-cognates was associated with activity in the anterior-medial left fusiform and right posterior cingulate cortices, suggesting that their successful retrieval may rely upon the access to semantic and lexical information, and even on the greater likelihood of errors.

0 Bookmarks
 · 
114 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: MOORMAN, S., A. Nicol. NEUROSCI BIOBEHAV REV volume(issue) XXX-XXX, 2014. Visual imprinting in chicks and song learning in songbirds are prominent model systems for the study of the neural mechanisms of memory. In both systems, neural lateralisation has been found to be involved in memory formation. Although many processes in the human brain are lateralised - spatial memory and musical processing involves mostly right hemisphere dominance, whilst language is mostly left hemisphere dominant - it is unclear what the function of lateralisation is. It might enhance brain capacity, make processing more efficient, or prevent occurrence of conflicting signals. In both avian paradigms we find memory-related lateralisation. We will discuss avian lateralisation findings and propose that birds provide a strong model for studying neural mechanisms of memory-related lateralisation.
    Neuroscience & Biobehavioral Reviews 07/2014; · 10.28 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: This study aimed at investigating the neural basis of word learning as a function of age and word type. Ten young and ten elderly French-speaking participants were trained by means of a computerized Spanish word program. Both age groups reached a similar naming accuracy, but the elderly required significantly more time. Despite equivalent performance, distinct neural networks characterized the ceiling. While the young cohort showed subcortical activations, the elderly recruited the left inferior frontal gyrus, the left lingual gyrus and the precuneus. The learning trajectory of the elderly, the neuroimaging findings together with their performance on the Stroop suggest that the young adults relied on control processing areas whereas the elderly relied on episodic memory circuits, which may reflect resorting to better preserved cognitive resources. Finally, the recruitment of visual processing areas by the elderly may reflect the impact of the language training method used.
    Brain and Language 05/2014; 135C:9-19. · 3.31 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Within the field of neuroscientific research on second language learning, considerable attention has been devoted to functional and recently also structural changes related to second language acquisition. The present literature review summarizes studies that investigated structural changes related to bilingualism. Furthermore, as recent evidence has suggested that native-like exposure to a second language (i.e., a naturalistic learning setting or immersion) considerably impacts second language learning, all findings are reflected with respect to the learning environment. Aggregating the existing evidence, we conclude that structural changes in left inferior frontal and inferior parietal regions have been observed in studies on cortical gray matter changes, while the anterior parts of the corpus callosum have been repeatedly found to reflect bilingualism in studies on white matter (WM) connectivity. Regarding the learning environment, no cortical alterations can be attributed specifically to naturalistic or classroom learning. With regard to WM changes, one might tentatively propose that changes in IFOF and SLF are possibly more prominently observed in studies investigating bilinguals with a naturalistic learning experience. However, future studies are needed to replicate and strengthen the existing evidence and to directly test the impact of naturalistic exposure on structural brain plasticity.
    Frontiers in Psychology 10/2014; 5:1116. · 2.80 Impact Factor

Full-text (2 Sources)

Download
115 Downloads
Available from
May 26, 2014