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There is ample theoretical justification for incorporating reflection exercises as a tool for preparing students for life beyond university, yet the utility of such exercises needs to be documented if resources are to be devoted to their implementation. This study describes the implementation and evaluates the effectiveness of a reflection exercise that was introduced in an entry-level undergraduate psychology course. Students completed four periodic reflection journals and submitted an essay summarizing their progress as learner at the end of the semester using examples from the journals to support their reflection. Multiple qualitative analysis methods were used to measure the reflective content of the summary essays. The analyses support the effectiveness of the exercise in promoting reflection on the process of learning including strengths, weaknesses, learning strategies, competence, efforts, and emotions. In addition, reviewing the reflective essays provided the instructor with invaluable insight into the students' experience. We conclude that reflection writing can be incorporated in undergraduate studies to encourage the development of life-long learning skills with reasonable time requirements. Suggestions for modes of implementation as well as future avenues of research are discussed.

Background: Face-identity processing declines with age. Few studies have examined whether face-identity processing abilities can be measured independently from general cognitive abilities in older adults (OA). This question has practical implications for the assessment of face-identity processing abilities in OA and theoretical implications for the notion of face processing as a specific ability. The present study examined the specificity of face memory and face matching abilities in OA aged 50+. Methods: Performance of younger adults (YA) and OA was measured on face tasks: Cambridge Face Memory Task (CFMT), the Glasgow Face Matching Task (GFMT), holistic processing; and tasks of general cognition: fluid intelligence, selective attention, and mental rotation. Data were analyzed using multiple regression models encompassing: (1) the CFMT/GFMT and measures of general cognition; and (2) all face processing tasks. Results: Across the two age groups, models encompassing all face tasks were significant and accounted for more variance in the data than models encompassing the CFMT/GFMT and measures of general cognition. General cognitive abilities accounted for 17% of variance for the GFMT (p < 0.01) and 3% for the CFMT (p > 0.05). Discussion: Our results suggest that face memory can be measured independently from general cognition using the CFMT in OA. Implications for the notion of a general face processing factor across the adult lifespan are discussed.

Fragile X syndrome (FXS) is the most common form of heritable mental retardation, affecting (~ around) 1 in 4000 males. The syndrome arises from expansion of a trinucleotide repeat in the 5'-untranslated region of the fragile X mental retardation 1 ("FMR1") gene, leading to methylation of the promoter sequence and lack of the fragile X mental retardation protein (FMRP). Affected individuals display a unique neurobehavioural phenotype that includes striking visual-motor deficits. Here we provide neurobiological and behavioural evidence that supports the hypothesis that these visual-motor deficits are attributable to a magnocellular (M) visual pathway impairment. Immunohistochemical staining of a lateral geniculate nucleus (LGN) of a normal human male revealed high FMRP basal expression selectively within the M layers, suggesting an increased susceptibility of these neurons to the lack of FMRP as occurs in FXS. Similar staining of monkey LGNs for quantification purposes revealed that the difference is not an artefact of cell size differences between M and parvocellular (P) neurons. Further, Nissl staining of the LGNs of a male FXS patient revealed alaminar nuclei comprised of a homogenous population of small sized neurons, providing anatomical and morphological support for the idea that an M pathway pathology exists in FXS. Consistent with these neurobiological data, we have found that male patients with FXS have reduced sensitivity for psychophysical stimuli that probe the M pathway but not for those that probe the P pathway, a complementary visual stream that performs a separate set of early visual operations. Finally, male patients with FXS performed poorly on a global motion task but not on a form perception task, suggesting that the M pathway thalamic deficit may have a selective impact on cortical visual functioning in the parietal lobe, which is known to be a major recipient of M pathway afferents via the primary visual cortex. Together, these findings provide the first evidence that the loss of a single gene product, FMRP, in humans leads to abnormal neuroanatomical morphology of the LGN and a concomitant selective visual deficit of the M pathway.

Using a comparative neuropsychological approach, the authors compared performance of younger and healthy older adults ages 65 and over on tasks originally developed to measure cognition in animals. A battery of 6 tasks was used to evaluate object discrimination, egocentric spatial abilities, visual and spatial working memory, and response shifting. Older adults performed more poorly than younger adults on tasks that evaluate egocentric spatial abilities, response shifting, and to a lesser extent object recognition. The two groups did not differ for tasks that evaluate spatial working memory and object discrimination. The impairments the authors observed in tasks that evaluate response shifting and object recognition are consistent with those found in canines and primates as well as those found in Alzheimer's disease. The results are consistent with the notion that cognitive processes supported by the amygdala and the orbitofrontal cortex are among the first to decline with increasing age in both humans and animals. Keywords: delayed nonmatching-to-sample task, object discrimination, reversal learning, spatial abilities, aging

Abstract Background The deep-sea hydrothermal vent mussel Bathymodiolus azoricus harbors thiotrophic and methanotrophic symbiotic bacteria in its gills. While the symbiotic relationship between this hydrothermal mussel and these chemoautotrophic bacteria has been described, the molecular processes involved in the cross-talking between symbionts and host, in the maintenance of the symbiois, in the influence of environmental parameters on gene expression, and in transcriptome variation across individuals remain poorly understood. In an attempt to understand how, and to what extent, this double symbiosis affects host gene expression, we used a transcriptomic approach to identify genes potentially regulated by symbiont characteristics, environmental conditions or both. This study was done on mussels from two contrasting populations. Results Subtractive libraries allowed the identification of about 1000 genes putatively regulated by symbiosis and/or environmental factors. Microarray analysis showed that 120 genes (3.5% of all genes) were differentially expressed between the Menez Gwen (MG) and Rainbow (Rb) vent fields. The total number of regulated genes in mussels harboring a high versus a low symbiont content did not differ significantly. With regard to the impact of symbiont content, only 1% of all genes were regulated by thiotrophic (SOX) and methanotrophic (MOX) bacteria content in MG mussels whereas 5.6% were regulated in mussels collected at Rb. MOX symbionts also impacted a higher proportion of genes than SOX in both vent fields. When host transcriptome expression was analyzed with respect to symbiont gene expression, it was related to symbiont quantity in each field. Conclusions Our study has produced a preliminary description of a transcriptomic response in a hydrothermal vent mussel host of both thiotrophic and methanotrophic symbiotic bacteria. This model can help to identify genes involved in the maintenance of symbiosis or regulated by environmental parameters. Our results provide evidence of symbiont effect on transcriptome regulation, with differences related to type of symbiont, even though the relative percentage of genes involved remains limited. Differences observed between the vent site indicate that environment strongly influences transcriptome regulation and impacts both activity and relative abundance of each symbiont. Among all these genes, those participating in recognition, the immune system, oxidative stress, and energy metabolism constitute new promising targets for extended studies on symbiosis and the effect of environmental parameters on the symbiotic relationships in B. azoricus.

Abstract Background Alvinella pompejana is a representative of Annelids, a key phylum for evo-devo studies that is still poorly studied at the sequence level. A. pompejana inhabits deep-sea hydrothermal vents and is currently known as one of the most thermotolerant Eukaryotes in marine environments, withstanding the largest known chemical and thermal ranges (from 5 to 105°C). This tube-dwelling worm forms dense colonies on the surface of hydrothermal chimneys and can withstand long periods of hypo/anoxia and long phases of exposure to hydrogen sulphides. A. pompejana specifically inhabits chimney walls of hydrothermal vents on the East Pacific Rise. To survive, Alvinella has developed numerous adaptations at the physiological and molecular levels, such as an increase in the thermostability of proteins and protein complexes. It represents an outstanding model organism for studying adaptation to harsh physicochemical conditions and for isolating stable macromolecules resistant to high temperatures. Results We have constructed four full length enriched cDNA libraries to investigate the biology and evolution of this intriguing animal. Analysis of more than 75,000 high quality reads led to the identification of 15,858 transcripts and 9,221 putative protein sequences. Our annotation reveals a good coverage of most animal pathways and networks with a prevalence of transcripts involved in oxidative stress resistance, detoxification, anti-bacterial defence, and heat shock protection. Alvinella proteins seem to show a slow evolutionary rate and a higher similarity with proteins from Vertebrates compared to proteins from Arthropods or Nematodes. Their composition shows enrichment in positively charged amino acids that might contribute to their thermostability. The gene content of Alvinella reveals that an important pool of genes previously considered to be specific to Deuterostomes were in fact already present in the last common ancestor of the Bilaterian animals, but have been secondarily lost in model invertebrates. This pool is enriched in glycoproteins that play a key role in intercellular communication, hormonal regulation and immunity. Conclusions Our study starts to unravel the gene content and sequence evolution of a deep-sea annelid, revealing key features in eukaryote adaptation to extreme environmental conditions and highlighting the proximity of Annelids and Vertebrates.