The statistical neuroanatomy of frontal networks in the macaque

We were interested in gaining insight into the functional properties of frontal networks based upon their anatomical inputs. We took a neuroinformatics approach, carrying out maximum likelihood hierarchical cluster analysis on 25 frontal cortical areas based upon their anatomical connections, with 68 input areas representing exterosensory, chemosensory, motor, limbic, and other frontal inputs. The analysis revealed a set of statistically robust clusters. We used these clusters to divide the frontal areas into 5 groups, including ventral-lateral, ventral-medial, dorsal-medial, dorsal-lateral, and caudal-orbital groups. Each of these groups was defined by a unique set of inputs. This organization provides insight into the differential roles of each group of areas and suggests a gradient by which orbital and ventral-medial areas may be responsible for decision-making processes based on emotion and primary reinforcers, and lateral frontal areas are more involved in integrating affective and rational information into a common framework

To ware or Vapourware passing through Solutionism and Paleo-Future

UID/SOC/04647/2013The object of this paper is to discuss the concept(s) of Design Fiction(s), and to elaborate a critical re-definition of the termsfrom Literary Theory and Narratology’s stand-points. By so doing, it aims to propose a clarification of the types of objects frameable by Design Fiction (DF), and shorten the gap between the latter and Interactive Fiction (IF), IoT (Internet of Things) fictions and AR (Augmented Reality) whenever these practices are being used to tell stories. Smart-houses will be used as an example of successful DF narratives.publishersversionpublishe

Contrasting prefrontal cortex contributions to episodic memory dysfunction in behavioural variant frontotemporal dementia and alzheimer's disease

Recent evidence has questioned the integrity of episodic memory in behavioural variant frontotemporal dementia (bvFTD), where recall performance is impaired to the same extent as in Alzheimer's disease (AD). While these deficits appear to be mediated by divergent patterns of brain atrophy, there is evidence to suggest that certain prefrontal regions are implicated across both patient groups. In this study we sought to further elucidate the dorsolateral (DLPFC) and ventromedial (VMPFC) prefrontal contributions to episodic memory impairment in bvFTD and AD. Performance on episodic memory tasks and neuropsychological measures typically tapping into either DLPFC or VMPFC functions was assessed in 22 bvFTD, 32 AD patients and 35 age- and education-matched controls. Behaviourally, patient groups did not differ on measures of episodic memory recall or DLPFC-mediated executive functions. BvFTD patients were significantly more impaired on measures of VMPFC-mediated executive functions. Composite measures of the recall, DLPFC and VMPFC task scores were covaried against the T1 MRI scans of all participants to identify regions of atrophy correlating with performance on these tasks. Imaging analysis showed that impaired recall performance is associated with divergent patterns of PFC atrophy in bvFTD and AD. Whereas in bvFTD, PFC atrophy covariates for recall encompassed both DLPFC and VMPFC regions, only the DLPFC was implicated in AD. Our results suggest that episodic memory deficits in bvFTD and AD are underpinned by divergent prefrontal mechanisms. Moreover, we argue that these differences are not adequately captured by existing neuropsychological measures

The origin of large molecules in primordial autocatalytic reaction networks

Large molecules such as proteins and nucleic acids are crucial for life, yet their primordial origin remains a major puzzle. The production of large molecules, as we know it today, requires good catalysts, and the only good catalysts we know that can accomplish this task consist of large molecules. Thus the origin of large molecules is a chicken and egg problem in chemistry. Here we present a mechanism, based on autocatalytic sets (ACSs), that is a possible solution to this problem. We discuss a mathematical model describing the population dynamics of molecules in a stylized but prebiotically plausible chemistry. Large molecules can be produced in this chemistry by the coalescing of smaller ones, with the smallest molecules, the `food set', being buffered. Some of the reactions can be catalyzed by molecules within the chemistry with varying catalytic strengths. Normally the concentrations of large molecules in such a scenario are very small, diminishing exponentially with their size. ACSs, if present in the catalytic network, can focus the resources of the system into a sparse set of molecules. ACSs can produce a bistability in the population dynamics and, in particular, steady states wherein the ACS molecules dominate the population. However to reach these steady states from initial conditions that contain only the food set typically requires very large catalytic strengths, growing exponentially with the size of the catalyst molecule. We present a solution to this problem by studying `nested ACSs', a structure in which a small ACS is connected to a larger one and reinforces it. We show that when the network contains a cascade of nested ACSs with the catalytic strengths of molecules increasing gradually with their size (e.g., as a power law), a sparse subset of molecules including some very large molecules can come to dominate the system.Comment: 49 pages, 17 figures including supporting informatio

Activation of ERK1/2 MAP kinases in familial amyloidotic polyneuropathy

J Neurochem. 2006 Apr;97(1):151-61. Epub 2006 Mar 3. Activation of ERK1/2 MAP kinases in familial amyloidotic polyneuropathy. Monteiro FA, Sousa MM, Cardoso I, do Amaral JB, Guimarães A, Saraiva MJ. Molecular Neurobiology, Instituto de Biologia Celular e Molecular, ICBAS, University of Porto, and Estomatology, Maxillofacial Surgery, Hospital Geral de Santo António, Portugal. Abstract Familial amyloidotic polyneuropathy (FAP) is a neurodegenerative disorder characterized by the extracellular deposition of transthyretin (TTR), especially in the PNS. Given the invasiveness of nerve biopsy, salivary glands (SG) from FAP patients were used previously in microarray analysis; mitogen-activated protein (MAP) kinase phosphatase 1 (MKP-1) was down-regulated in FAP. Results were validated by RT-PCR and immunohistochemistry both in SG and in nerve biopsies of different stages of disease progression. MKP-3 was also down-regulated in FAP SG biopsies. Given the relationship between MKPs and MAPKs, the latter were investigated. Only extracellular signal-regulated kinases 1/2 (ERK1/2) displayed increased activation in FAP SG and nerves. ERK1/2 kinase (MEK1/2) activation was also up-regulated in FAP nerves. In addition, an FAP transgenic mouse model revealed increased ERK1/2 activation in peripheral nerve affected with TTR deposition when compared to control animals. Cultured rat Schwannoma cell line treatment with TTR aggregates stimulated ERK1/2 activation, which was partially mediated by the receptor for advanced glycation end-products (RAGE). Moreover, caspase-3 activation triggered by TTR aggregates was abrogated by U0126, a MEK1/2 inhibitor, indicating that ERK1/2 activation is essential for TTR aggregates-induced cytotoxicity. Taken together, these data suggest that abnormally sustained activation of ERK in FAP may represent an early signaling cascade leading to neurodegeneration. PMID: 16515552 [PubMed - indexed for MEDLINE

A proposal for a coordinated effort for the determination of brainwide neuroanatomical connectivity in model organisms at a mesoscopic scale

In this era of complete genomes, our knowledge of neuroanatomical circuitry remains surprisingly sparse. Such knowledge is however critical both for basic and clinical research into brain function. Here we advocate for a concerted effort to fill this gap, through systematic, experimental mapping of neural circuits at a mesoscopic scale of resolution suitable for comprehensive, brain-wide coverage, using injections of tracers or viral vectors. We detail the scientific and medical rationale and briefly review existing knowledge and experimental techniques. We define a set of desiderata, including brain-wide coverage; validated and extensible experimental techniques suitable for standardization and automation; centralized, open access data repository; compatibility with existing resources, and tractability with current informatics technology. We discuss a hypothetical but tractable plan for mouse, additional efforts for the macaque, and technique development for human. We estimate that the mouse connectivity project could be completed within five years with a comparatively modest budget.Comment: 41 page

Mood and cognition in healthy older European adults: the Zenith study

YesBackground: The study aim was to determine if state and trait intra-individual measures of everyday affect predict cognitive functioning in healthy older community dwelling European adults (n = 387), aged 55-87 years. Methods: Participants were recruited from centres in France, Italy and Northern Ireland. Trait level and variability in positive and negative affect (PA and NA) were assessed using self-administered PANAS scales, four times a day for four days. State mood was assessed by one PANAS scale prior to assessment of recognition memory, spatial working memory, reaction time and sustained attention using the CANTAB computerized test battery. Results: A series of hierarchical regression analyses were carried out, one for each measure of cognitive function as the dependent variable, and socio-demographic variables (age, sex and social class), state and trait mood measures as the predictors. State PA and NA were both predictive of spatial working memory prior to looking at the contribution of trait mood. Trait PA and its variability were predictive of sustained attention. In the final step of the regression analyses, trait PA variability predicted greater sustained attention, whereas state NA predicted fewer spatial working memory errors, accounting for a very small percentage of the variance (1-2%) in the respective tests. Conclusion: Moods, by and large, have a small transient effect on cognition in this older sample

Produção de memórias falsas com listas de associados : análise do efeito do nível de processamento e da natureza da prova de memória

As memórias falsas têm sido amplamente estudadas com base num procedimento experimental designado paradigma DRM (Deese/Roediger/McDermott). Esse paradigma promove a criação de ilusões de memória a partir da apresentação de listas de palavras associadas a um item que não consta da lista. Uma das linhas de investigação com o paradigma DRM visa identificar o momento da criação das falsas memórias e explicar os mecanismos que estão na sua origem. Neste artigo, pretendemos fazer uma revisão da investigação sobre o efeito do nível de processamento e da natureza da tarefa de memória na facilitação ou inibição da produção de memórias falsas com listas de associados semânticos.False memories have been widely studied using an experimental procedure called DRM paradigm (Deese/Roediger/McDermott). This paradigm produces memory illusions due to the presentation of lists of words associated to a critical nonpresented word. One line of research on this topic aims at identifying the moment when the false memories are created and the explanation of the mechanisms underling false memories. In this paper we present a review about the effect of level-of-processing and the nature of memory task for the boost or inhibition of false memories created by means of lists of semantic associates.Le paradigme DRM (Deese/Roediger/McDermott) est un des plus connus et plus robustes parmi les études des faux mémoires dans le contexte du laboratoire. Ce paradigme permet la création d illusions de mémoire à partir des mots sémantiquement associés à un item qui n a pas été présenté. Au milieu des investigations basées sur le paradigme DRM il y a des études dont l objectif est d identifier e d´expliquer les mécanismes qui sont à l origine de la production des faux mémoires. Plus spécifiquement, on a pour but de faire une révision de la recherche sur l effet du niveau de codification et de la nature des tâches de mémoire sur la facilitation ou l´inhibition de la production de faux mémoires à partir des mots sémantiquement associés.Los falsos recuerdos han sido muy estudiados mediante la aplicación del paradigma DRM (Deese/Roediger/McDermott). El paradigma permite producir ilusiones de memoria tras la presentación de listas de palabras asociadas a una palabra que no se incluye en la lista. Una de las líneas de investigación que utilizan el paradigma DRM busca identificar el preciso momento de la creación de falsos recuerdos y explicar los mecanismos que originan ese efecto. El objetivo de este artículo es hacer una revisión de la investigación sobre el efecto de los niveles de procesamiento y la naturaleza de la tarea de memoria en la facilitación y inhibición de la producción de falsos recuerdos con listas de asociados semánticos.Fundação para a Ciência e a Tecnologia (FCT)Centro de Investigação em Psicologia da Universidade do Minho (CIPsi

Bluetooth Tracking Approach For User Assistance Based In Sequential Patterns Analysis.

As a civilization, we are drowning in a raging torrent of data, of our own making, that is being harvested by our collective technologies and systems (e.g. Fitbit, phones). However, data itself is of no utility unless it is converted into beneficial knowledge. Design patterns have been shown to be a pragmatic solution to control and manage information flows and provide order and mean-ing to data within a given context. Assisting users within their daily activities has become a key aspect for modern Artificial Intelligence Systems. Neverthe-less, although the GPS technologies work well for outside location, indoor posi-tioning is still problematic, while is a vital awareness component in ambient as-sistance. This paper shows a preliminary Bluetooth tracking system with a focus on the user’s transition between areas of interest. Our work aims to shed light on how the term design patterns can be applied for studying human behavior patterns in the smart environment