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Advances in fluorescence microscopy enable monitoring larger brain areas in-vivo with finer time resolution. The resulting data rates require reproducible analysis pipelines that are reliable, fully automated, and scalable to datasets generated over the course of months. We present CaImAn, an open-source library for calcium imaging data analysis. CaImAn provides automatic and scalable methods to address problems common to pre-processing, including motion correction, neural activity identification, and registration across different sessions of data collection. It does this while requiring minimal user intervention, with good scalability on computers ranging from laptops to high-performance computing clusters. CaImAn is suitable for two-photon and one-photon imaging, and also enables real-time analysis on streaming data. To benchmark the performance of CaImAn we collected and combined a corpus of manual annotations from multiple labelers on nine mouse two-photon datasets. We demonstrate that CaImAn achieves near-human performance in detecting locations of active neurons., eLife digest The human brain contains billions of cells called neurons that rapidly carry information from one part of the brain to another. Progress in medical research and healthcare is hindered by the difficulty in understanding precisely which neurons are active at any given time. New brain imaging techniques and genetic tools allow researchers to track the activity of thousands of neurons in living animals over many months. However, these experiments produce large volumes of data that researchers currently have to analyze manually, which can take a long time and generate irreproducible results. There is a need to develop new computational tools to analyze such data. The new tools should be able to operate on standard computers rather than just specialist equipment as this would limit the use of the solutions to particularly well-funded research teams. Ideally, the tools should also be able to operate in real-time as several experimental and therapeutic scenarios, like the control of robotic limbs, require this. To address this need, Giovannucci et al. developed a new software package called CaImAn to analyze brain images on a large scale. Firstly, the team developed algorithms that are suitable to analyze large sets of data on laptops and other standard computing equipment. These algorithms were then adapted to operate online in real-time. To test how well the new software performs against manual analysis by human researchers, Giovannucci et al. asked several trained human annotators to identify active neurons that were round or donut-shaped in several sets of imaging data from mouse brains. Each set of data was independently analyzed by three or four researchers who then discussed any neurons they disagreed on to generate a ‘consensus annotation’. Giovannucci et al. then used CaImAn to analyze the same sets of data and compared the results to the consensus annotations. This demonstrated that CaImAn is nearly as good as human researchers at identifying active neurons in brain images. CaImAn provides a quicker method to analyze large sets of brain imaging data and is currently used by over a hundred laboratories across the world. The software is open source, meaning that it is freely-available and that users are encouraged to customize it and collaborate with other users to develop it further.

Advances in fluorescence microscopy enable monitoring larger brain areasin-vivowith finer time resolution. The resulting data rates require reproducible analysis pipelines that are reliable, fully automated, and scalable to datasets generated over the course of months. Here we present CaImAn, an open-source library for calcium imaging data analysis. CaImAn provides automatic and scalable methods to address problems common to pre-processing, including motion correction, neural activity identification, and registration across different sessions of data collection. It does this while requiring minimal user intervention, with good performance on computers ranging from laptops to high-performance computing clusters. CaImAn is suitable for two-photon and one-photon imaging, and also enables real-time analysis on streaming data. To benchmark the performance of CaImAn we collected a corpus of ground truth annotations from multiple labelers on nine mouse two-photon datasets. We demonstrate that CaImAn achieves near-human performance in detecting locations of active neurons.

Two studies were performed that compared a "Paired" condition in which participants studied paired associates with a "Generated" condition in which participants completed word fragments to produce paired associates. In both tasks, participants were responsible for memory of the material either studied or generated. The experiments revealed significant differences between the responses of a predefined prefrontal region and a predefined parietal region. The parietal region responded more in the Generated condition than the Paired condition, whereas there was no difference in the prefrontal region. On the other hand, the prefrontal region responded to the delay between study and test in both the Paired and Generated conditions, whereas the parietal region only responded to delay in the Generated condition. This pattern of results is consistent with the hypothesis that the parietal region is responsive to changes in problem representation and the prefrontal region to retrieval operations. An information-processing model embodying these assumptions was fit to the blood oxygen level-dependent responses in these regions.

What is the role of the left prefrontal cortex in the controlled retrieval of learned information? We present a theory of declarative retrieval that posits that the amount of control exerted by this region during retrieval is inversely proportional to 1) the frequency and recency of previous experiences with the retrieved memory and 2) the associative strength between the current context and the retrieved memory. This theory is rational in the sense that it claims that declarative retrieval is highly sensitive to the statistical regularities in the environment. We demonstrate how our theory produces precise predictions of response time and neural activity during recall and test these predictions in an experiment that manipulates the frequency of previous experiences and the associative strength to the retrieval cues. Our findings suggest that the control process performed by the left prefrontal cortex directly reflects the demands of the environment on memory.

Background A number of methodological weaknesses have contributed to our relatively poor understanding of the impact on children of having a brother or sister with a disability. These include a focus on poor adjustment, using multidiagnostic groups, inadequate matching, and a failure to consider the perspectives of children and parents together. Method This study compared the adjustment of 53 siblings of a child with Down syndrome with a comparison group of siblings of children who were developing typically. Children were matched on a case-by-case basis for gender, age and position in family. Families were matched for family size and father's occupation. The age range of the target siblings was 7-14 years. Data were gathered from mothers, fathers and siblings. Results There were no significant differences between the groups on adjustment measures. These included parent perceptions of externalizing and internalizing behaviours, parent perceptions of sibling competence, and sibling perceptions of their own competence and self-worth. Associations between measures of adjustment and child reports of their contribution to household functioning depended on sex rather than group membership. There was an association between parental reports of externalizing behaviour and sibling relationships with the brother/sister closest in age. Conclusions Having a brother or sister with Down syndrome does not inevitably lead to poor adjustment. Examination of within-family processes would appear to be more useful in identifying children at risk than merely group membership.

Developmental assessments are reported for two cohorts of Brisbane children with Down syndrome at chronological ages from 11 to 14 years. Cohort 1 was born during 1973 to 1974 while Cohort 2 was born from May 1976 to December 1978. These cohorts provided an opportunity of studying the long‐term effects of early intervention as a history‐graded influence on development; one cohort was born before early intervention became widely available whereas by the time the other children were born, a variety of programs were being offered children with disabilities. No significant cohort differences were found in MA at 11 years, 12 years and 14 years CA, in non‐verbal scores at 11 years and 12 years CA, or in adaptive behaviour scores near 13 years CA. There was no evidence of a final plateau in MA. When the cohorts were divided on the basis of early intervention commencement age, frequency and duration of attendance, there were again no group differences. SES, mothers’ education, and gender were significant...

MOTHERS AND TEACHERS of 94 children (53 boys) with Down syndrome, between 8 and 14 years of age, rated the children on a temperament scale and provided an overall impression as to whether the child was difficult in comparison with other children. Maternal ratings on the Middle Childhood Questionnaire showed significant differences from standardization scores. Children with Down syndrome were given ratings as less active, more predictable, of more positive mood, less persistent, and more distractible. Some of these dimensions favour the amiable personality stereotype for the syndrome but low persistence was associated with maternal impressions of difficulty. There was little agreement between mothers and teachers regarding the individual children who were rated as being significantly easier or more difficult than other children. Results with a subgroup (n = 32) showed that externalizing behaviours were significantly related to both mother and teacher impressions of difficulty and that mothers also found in...

Down syndrome occurs in all parts of the world. It is not restricted to any one race, culture, social class, or historical period. Evidence of the syndrome dates back to artefacts of the Olmecs in ancient Mexico (Stratford, 1989) although the first detailed and systematic description by Langdon Down came much later, in 1866.

Fifty-four siblings of children with Down syndrome and their parents and an individually matched group of comparison children and parents provided data about the quality of sibling relationships. There were no group differences in parental reports, but siblings of children with Down syndrome reported less unkindness and, if in a same-sex dyad, more empathy than did comparison children. There were differences between same-sex and opposite-sex dyads regarding avoidance and frequency of sibling positive and negative interactions. There were no group or sex differences in children's reports of their interactions with parents or contribution to household chores. Siblings of a child with Down syndrome participated in more caregiving activities. Caregiving was associated with empathy and involvement on the relationship questionnaire.

The early education of infants with Down syndrome has been strongly influenced by studies highlighting the importance of the environment. These studies encouraged the belief that intelligence is not fixed and that early experience is critical to the course of development. Since the origins of a decline in IQ for Down syndrome had been traced to early infancy, it was hoped that early intervention programs might halt or even reverse this decline. The de-institutionalization movement converged with these studies to emphasize the home as a teaching environment and to view the mother as a teacher. It is suggested that the concept of the environment should expand beyond the family and that professionals should consider their own role in terms of the social ecology of the family. The programs need also to address the specific arousal needs of the infant with Down syndrome and to include motivational aspects in addition to cognitive measures when evaluating the effects of infant education.

The mothers of 23 Down's syndrome children were asked to complete the Behavioral Style Questionnaire (BSQ) concerning the temperament characteristics of their child. They were also interviewed with the Implicit Parental Learning Theory (IPLET) Scale, which asked how they would handle certain specified child behaviors. Mothers of children with temperament rated as easy responded to the IPLET situations with more direct teaching responses and with less verbal expression of negative emotions than mothers of more difficult children. In addition, there were significant associations between maternal IPLET response and the activity, rhythm, approach, adaptability, and mood dimensions of the BSQ.

A questionnaire measuring attitudes toward mainstreaming was completed by teachers and parents at two primary schools, one of which had initiated a mainstreaming program in Year 1 classes. Results indicated that attitudes of parents and teachers at this school were more negative than those of their counterparts at the school with no mainstreaming program. Despite this apparent relationship between contact with disabled children and a negative attitude towards mainstreaming, a significant association was found between amount of experience with disabled children and a positive attitude towards mainstreaming. Among explanations proposed for these discrepant findings is the suggestion that attitudes expressed prior to experience with mainstreaming may not be an accurate guide to views held after its implementation.