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The anterior cingulate cortex (ACC) is a key structure implicated in the regulation of cognitive control (CC). Previous studies suggest that variability in the ACC sulcal pattern—a neurodevelopmental marker unaffected by maturation or plasticity after birth—is associated with intersubject differences in CC performance. Here, we investigated whether bilingual experience modulates the effects of ACC sulcal variability on CC performance across the lifespan. Using structural MRI, we first established the distribution of the ACC sulcal patterns in a large sample of healthy individuals (N = 270) differing on gender and ethnicity. Second, a participants’ subsample (N = 157) was selected to test whether CC performance was differentially affected by ACC sulcation in bilinguals and monolinguals across age. A prevalent leftward asymmetry unaffected by gender or ethnicity was reported. Sulcal variability in the ACC predicted CC performance differently in bilinguals and monolinguals, with a reversed pattern of structure–function relationship: asymmetrical versus symmetrical ACC sulcal patterns were associated with a performance advantage in monolinguals and a performance detriment to bilinguals and vice versa. Altogether, these findings provide novel insights on the dynamic interplay between early neurodevelopment, environmental background and cognitive efficiency across age.

Evidence that bilingualism protects against age-related neurocognitive decline is mixed. One relatively consis- tent finding is that bilingual seniors have greater grey matter volume (GMV) in regions implicated in executive control (EC) and language processing. Here, we compare the neuroplastic effects of bilingual experience on the EC network of young and aging populations directly, and for the first time we evaluate the extent to which such effects may predict executive control performance across age. We used GMV as an index of neural reserve and response time (RT) performance on the Flanker task for measuring EC efficiency. In the presence of age-related widespread GM deterioration, bilinguals had greater GMV than monolinguals in key regions of interest across age. Moreover, whereas EC performance in monolingual seniors was strictly related to GMV, this was not ob- served for bilingual seniors or younger participants in either group. Interactions between expected effects-of-age and language group on the relationships between GMV and RT suggested that bilingualism affords differential benefits across the lifespan. In younger participants, greater GMV offered no behavioral benefit on EC perfor- mance, whilst it did for seniors. It thus appears that age-related cognitive decline following GMV loss in the EC network is delayed in bilinguals.

Neuroimaging studies suggest that the neural network involved in language control may not be specific to bi-/multilingualism but is part of a domain-general executive control system. We report a trilingual case of a Cantonese (L1), English (L2), and Mandarin (L3) speaker, Dr. T, who sustained a brain injury at the age of 77 causing lesions in the left frontal lobe and in the left temporo-parietal areas resulting in fluent aphasia. Dr. T's executive functions were impaired according to a modified version of the Stroop color-word test and the Wisconsin Card Sorting Test performance was characterized by frequent perseveration errors. Dr. T demonstrated pathological language switching and mixing across her three languages. Code switching in Cantonese was more prominent in discourse production than confrontation naming. Our case suggests that voluntary control of spoken word production in trilingual speakers shares neural substrata in the frontobasal ganglia system with domain-general executive control mechanisms. One prediction is that lesions to such a system would give rise to both pathological switching and impairments of executive functions in trilingual speakers.

We report a patient with non-fluent Primary Progressive Aphasia who was premorbidly literate in two alphabetic scripts, Hungarian (L1) and English (L2). Testing was performed over a two-year period to assess the impact of progressive illness on oral reading and repetition of single words. Results showed significant decline in oral reading in both languages, and an effect of language status in favour of oral reading in L1. Phonological complexity was a significant predictor of oral reading decline in both languages. Of interest, we observed an effect of language status on task performance whereby repetition was better in L2 than L1 but oral reading was better in L1 than L2. We conclude that language status has an effect on repetition and oral reading abilities for bilingual speakers with non-fluent Primary Progressive Aphasia.

The Sepon. Laos, Cu processing plant was designed to treat 1 300 000 tpa of run-of-mine ore to produce 60 000 tpa of Cu cathode. The grinding circuit is operated under highly acidic conditions and a number of operational issues were encountered, including underestimation of ceramic grinding media consumption. A continuous improvement process was implemented in order to reach the design mill throughput of 170 dry t/h. Modifications included changes to the primary crusher facility, replacement of ceramic with high chrome steel grinding media, the introduction of a sieve bend into the milling circuit to remove pyrite fines when processing high-pyrite grade ore and improvements to linear screen throughput using polyester cloth. Total throughput rates in excess of 200 t/h are now regularly achieved., The Sepon. Laos, Cu processing plant was designed to treat 1 300 000 tpa of run-of-mine ore to produce 60 000 tpa of Cu cathode. The grinding circuit is operated under highly acidic conditions and a number of operational issues were encountered, including underestimation of ceramic grinding media consumption. A continuous improvement process was implemented in order to reach the design mill throughput of 170 dry t/h. Modifications included changes to the primary crusher facility, replacement of ceramic with high chrome steel grinding media, the introduction of a sieve bend into the milling circuit to remove pyrite fines when processing high-pyrite grade ore and improvements to linear screen throughput using polyester cloth. Total throughput rates in excess of 200 t/h are now regularly achieved.

The presence of a phonological relationship between a context word (cap) and the name of a target picture (cat) facilitates picture naming in the picture–word interference task in alphabetic languages such as English and Dutch. Neuroimaging studies of picture naming in English suggest distinct regions of brain activity are involved in phonological priming relative to a baseline control.