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Objective: Research suggests that prospective memory (PM) is impaired from the very early stages of Alzheimer's disease (AD). We sought to further characterize this impairment in patients with mild AD, using a virtual reality (VR) task to provide ecological assessment of PM. Methods: Fifteen cognitively normal older individuals (76.47 years old ± 4.14, MMSE: 28.80 ± 1.21), and 17 patients with mild AD (79.29 years old ± 4.45, MMSE: 22.82 ± 2.83) were asked to recall the prospective and retrospective components of seven intentions in a virtual town task. Six intentions were event-based, where the prospective cue was either highly (three intentions) or weakly (three intentions) associated with the retrospective component. The remaining intention was time-based. All participants completed a neuropsychological assessment of episodic memory, semantic memory and executive functioning. Non-parametric tests were used to compare the two groups on the different intentions types and components. Correlations between cognition and PM scores were then realized to further understand the cognitive correlates of the PM impairment in patients with AD. Results: Overall, patients with Alzheimer disease recalled fewer intentions than controls, with the retrospective component and time-based intentions being the most challenging for them. The strength of the association between the prospective and retrospective components, however, had no effect on their performance. Event-based PM impairment, as well as deficit in the recall of prospective component correlated with memory and executive functions performance. Conclusion: PM is impaired in AD. Both automatic and controlled processes of PM retrieval are disturbed. This study also confirms the reliability of VR for assessing complex cognitive functions such as PM.

Memory is one of the most important cognitive functions in a person's life as it is essential for recalling personal memories and performing many everyday tasks. Although a huge number of studies have been conducted in the field, only a few of them investigated memory in realistic situations, due to methodological issues. The various tools that have been developed using virtual environments (VEs) have gained popularity in cognitive psychology and neuropsychology because they enable to create naturalistic and controlled situations, and are thus particularly adapted to the study of episodic memory (EM), for which an ecological evaluation is of prime importance. EM is the conscious recollection of personal events combined with their phenomenological and spatiotemporal encoding contexts. Using an original paradigm in a VE, the objective of the present study was to characterize the construction of episodic memories. While the concept of working memory has become central in the understanding of a wide range of cognitive functions, its role in the integration of episodic memories has seldom been assessed in an ecological context. This experiment aimed at filling this gap by studying how EM is affected by concurrent tasks requiring working memory resources in a realistic situation. Participants navigated in a virtual town and had to memorize as many elements in their spatiotemporal context as they could. During learning, participants had either to perform a concurrent task meant to prevent maintenance through the phonological loop, or a task aimed at preventing maintenance through the visuospatial sketchpad, or no concurrent task. EM was assessed in a recall test performed after learning through various scores measuring the what, where and when of the memories. Results showed that, compared to the control condition with no concurrent task, the prevention of maintenance through the phonological loop had a deleterious impact only on the encoding of central elements. By contrast, the prevention of visuo-spatial maintenance interfered both with the encoding of the temporal context and with the binding. These results suggest that the integration of realistic episodic memories relies on different working memory processes that depend on the nature of the traces.

In a discrimination experiment on several Tashlhiyt Berber singleton-geminate contrasts, we find that French listeners encounter substantial difficulty compared to native speakers. Native listeners of Tashlhiyt perform near ceiling level on all contrasts. French listeners perform better on final contrasts such as fit-fitt than initial contrasts such as bi-bbi or sir-ssir. That is, French listeners are more sensitive to silent closure duration in word-final voiceless stops than to either voiced murmur or frication duration of fully voiced stops or voiceless fricatives in word-initial position. We propose, tentatively, that native speakers of French, a language in which gemination is usually not considered to be phonemic, have not acquired quantity contrasts but yet exhibit a presumably universal sensitivity to rhythm, whereby listeners are able to perceive and compare the relative temporal distance between beats given by successive salient phonetic events such as a sequence of vowel nuclei.

This study investigates the development of landmark and route knowledge in complex wayfinding situations. It focuses on how children (aged 6, 8, and 10 years) and young adults (n = 79) indicate, recognize, and bind landmarks and directions in both verbal and visuo-spatial tasks after learning a virtual route. Performance in these tasks is also related to general verbal and visuo-spatial abilities as assessed by independent standardized tests (attention, working memory, perception of direction, production and comprehension of spatial terms, sentences and stories). The results first show that the quantity and quality of landmarks and directions produced and recognized by participants in both verbal and visuo-spatial tasks increased with age. In addition, an increase with age was observed in participants' selection of decisional landmarks (i.e., landmarks associated with a change of direction), as well as in their capacity to bind landmarks and directions. Our results support the view that children first acquire landmark knowledge, then route knowledge, as shown by their late developing ability to bind knowledge of directions and landmarks. Overall, the quality of verbal and visuo-spatial information in participants' spatial representations was found to vary mostly with their visuo-spatial abilities (attention and perception of directions) and not with their verbal abilities. Interestingly, however, when asked to recognize landmarks encountered during the route, participants show an increasing bias with age toward choosing a related landmark of the same category, regardless of its visual characteristics, i.e., they incorrectly choose the picture of another fountain. The discussion highlights the need for further studies to determine more precisely the role of verbal and visuo-spatial knowledge and the nature of how children learn to represent and memorize routes.

Skill learning is the improvement in perceptual, cognitive, or motor performance following practice. Expert performance levels can be achieved with well-organized knowledge, using sophisticated and specific mental representations and cognitive processing, applying automatic sequences quickly and efficiently, being able to deal with large amounts of information, and many other challenging task demands and situations that otherwise paralyze the performance of novices. The neural reorganizations that occur with expertise reflect the optimization of the neurocognitive resources to deal with the complex computational load needed to achieve peak performance. As such, capitalizing on neuronal plasticity, brain modifications take place over time-practice and during the consolidation process. One major challenge is to investigate the neural substrates and cognitive mechanisms engaged in expertise, and to define "expertise" from its neural and cognitive underpinnings. Recent insights showed that many brain structures are recruited during task performance, but only activity in regions related to domain-specific knowledge distinguishes experts from novices. The present review focuses on three expertise domains placed across a motor to mental gradient of skill learning: sequential motor skill, mental simulation of the movement (motor imagery), and meditation as a paradigmatic example of "pure" mental training. We first describe results on each specific domain from the initial skill acquisition to expert performance, including recent results on the corresponding underlying neural mechanisms. We then discuss differences and similarities between these domains with the aim to identify the highlights of the neurocognitive processes underpinning expertise, and conclude with suggestions for future research.

In the last few decades there has been increasing interest in the role of the amygdala in psychiatric disorders and, in particular, in its contribution to the socio-emotional impairments in autism spectrum disorders (ASDs). Given that the amygdala is a component structure of the "social brain," several theoretical explanations compatible with amygdala dysfunction have been proposed to account for socio-emotional impairments in ASDs, including abnormal eye contact, gaze monitoring, face processing, mental state understanding, and empathy. Nevertheless, many theoretical accounts, based on the Amygdala Theory of Autism, fail to elucidate the complex pattern of impairments observed in this population, which extends beyond the social domain. As posited by the Relevance Detector theory (Sander et al., 2003), the human amygdala is a critical component of a brain circuit involved in the appraisal of self-relevant events that include, but are not restricted to, social stimuli. Here, we propose that the behavioral and social-emotional features of ASDs may be better understood in terms of a disruption in a "Relevance Detector Network" affecting the processing of stimuli that are relevant for the organism's self-regulating functions. In the present review, we will first summarize the main literature supporting the involvement of the amygdala in socio-emotional disturbances in ASDs. Next, we will present a revised version of the Amygdala Relevance Detector hypothesis and we will show that this theoretical framework can provide a better understanding of the heterogeneity of the impairments and symptomatology of ASDs. Finally, we will discuss some predictions of our model, and suggest new directions in the investigation of the role of the amygdala within the more generally disrupted cortical connectivity framework as a model of neural organization of the autistic brain.

TWO EXPERIMENTS INVESTIGATED WHETHER AND HOW THE LEARNING OF SPELLINGS BY FRENCH THIRD GRADERS IS INFLUENCED BY TWO GRAPHOTACTIC PATTERNS: consonants cannot double in word-initial position (Experiment 1) and consonants cannot double after single consonants (Experiment 2). Children silently read meaningful texts that contained three types of novel spellings: no doublet (e.g., mupile, guprane), doublet in a legal position (e.g., muppile, gupprane), and doublet in an illegal position (e.g., mmupile, guprrane). Orthographic learning was assessed with a task of spelling to dictation. In both experiments, children recalled items without doublets better than items with doublets. In Experiment 1, children recalled spellings with a doublet in illegal word-initial position better than spellings with a doublet in legal word-medial position, and almost all misspellings involved the omission of the doublet. The fact that the graphotactic violation in an item like mmupile was in the salient initial position may explain why children often remembered both the presence and the position of the doublet. In Experiment 2, children recalled non-words with a doublet before a single consonant (legal, e.g., gupprane) better than those with a doublet after a single consonant (illegal, e.g., guprrane). Omission of the doublet was the most frequent error for both types of items. Children also made some transposition errors on items with a doublet after a single consonant, recalling for example gupprane instead of guprrane. These results suggest that, when a doublet is in the hard-to-remember medial position, children sometimes remember that an item contains a doublet but not which letter is doubled. Their knowledge that double consonants can occur before but not after single consonants leads to transposition errors on items like guprrane. These results shed new light on the conditions under which children use general knowledge about the graphotactic patterns of their writing system to reconstruct spellings.

Use of morphologically related words often helps in selecting among spellings of sounds in French. For instance, final /wa/ may be spelled oi (e.g., envoi "sendoff"), oit (e.g., exploit "exploit"), ois (e.g., siamois, "siamese"), or oie (e.g., joie "joy"). The morphologically complex word exploiter "to exploit", with a pronounced t, can be used to indicate that the stem exploit is spelled with a silent t. We asked whether 8-year-old children benefited from such cues to learn new spellings. Children read silently stories which included two target nonwords, one presented in an opaque condition and the other in a morphological condition. In the opaque condition, the sentence provided semantic information (e.g., a vensois is a musical instrument) but no morphological information that could justify the spelling of the target word's final sound. Such justification was available in the morphological condition (e.g., the vensoisist plays the vensois instrument, which justifies that vensois includes a final silent s). 30 min after having read the stories, children's orthographic learning was assessed by asking them to choose the correct spelling of each nonword from among three phonologically plausible alternatives (e.g., vensois, vensoit, vensoie). Children chose correct spellings more often in the morphological condition than the opaque condition, even though the root (vensois) had been presented equally often in both conditions. That is, children benefited from information about the spelling of the morphologically complex word to learn the spelling of the stem.

Autobiographical memory (AM) comprises representation of both specific (episodic) and generic (semantic) personal information. Depression is characterized by a shift from episodic to semantic AM retrieval. According to theoretical models, this process ("overgeneralization"), would be linked to reduced executive resources. Moreover, "overgeneral" memories, accompanied by a negativity bias in depression, lead to a pervasive negative self-representation. As executive functions and AM specificity are also closely intricate among "non-clinical" populations, "overgeneral" memories could result in depressive emotional responses. Consequently, our hypothesis was that the neurocognitive profile of healthy subjects showing a rigid negative self-image would mimic that of patients. Executive functions and self-image were measured and brain activity was recorded, by means of fMRI, during episodic AMs retrieval in young healthy subjects. The results show an inverse correlation, that is, a more rigid and negative self-image produces lower performances in both executive and specific memories. Moreover, higher negative self-image is associated with decreased activity in the left ventro-lateral prefrontal and in the anterior cingulate cortex, repeatedly shown to exhibit altered functioning in depression. Activity in these regions, on the contrary, positively correlates with executive and memory performances, in line with their role in executive functions and AM retrieval. These findings suggest that rigid negative self-image could represent a marker or a vulnerability trait of depression by being linked to reduced executive function efficiency and episodic AM decline. These results are encouraging for psychotherapeutic approaches aimed at cognitive flexibility in depression and other psychiatric disorders.