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Autism spectrum disorders (ASDs) represent a formidable challenge for psychiatry and neuroscience because of their high prevalence, lifelong nature, complexity and substantial heterogeneity. Facing these obstacles requires large-scale multidisciplinary efforts. Although the field of genetics has pioneered data sharing for these reasons, neuroimaging had not kept pace. In response, we introduce the Autism Brain Imaging Data Exchange (ABIDE)-a grassroots consortium aggregating and openly sharing 1112 existing resting-state functional magnetic resonance imaging (R-fMRI) data sets with corresponding structural MRI and phenotypic information from 539 individuals with ASDs and 573 age-matched typical controls (TCs; 7-64 years) (http://fcon_1000.projects.nitrc.org/indi/abide/). Here, we present this resource and demonstrate its suitability for advancing knowledge of ASD neurobiology based on analyses of 360 male subjects with ASDs and 403 male age-matched TCs. We focused on whole-brain intrinsic functional connectivity and also survey a range of voxel-wise measures of intrinsic functional brain architecture. Whole-brain analyses reconciled seemingly disparate themes of both hypo- and hyperconnectivity in the ASD literature; both were detected, although hypoconnectivity dominated, particularly for corticocortical and interhemispheric functional connectivity. Exploratory analyses using an array of regional metrics of intrinsic brain function converged on common loci of dysfunction in ASDs (mid- and posterior insula and posterior cingulate cortex), and highlighted less commonly explored regions such as the thalamus. The survey of the ABIDE R-fMRI data sets provides unprecedented demonstrations of both replication and novel discovery. By pooling multiple international data sets, ABIDE is expected to accelerate the pace of discovery setting the stage for the next generation of ASD studies. [ABSTRACT FROM AUTHOR]

Membrane wastewater treatment plants (WWTPs) have several advantages compared with conventionally designed WWTPS with classical purification techniques. The filtration process is the key to their commercial success in Germany with respect to energy consumption and effectiveness, enabled by the optimization of filtration using a dynamic simulation model. This work is focused on the development of a robust, flexible and practically applicable membrane simulation model for submerged hollow-fibre and flat-sheet membrane modules. The model is based on standard parameters usually measured on membrane WWTPs. The performance of the model is demonstrated by successful calibration and validation for three different full-scale membrane WWTPs achieving good results. Furthermore, the model is combinable with Activated Sludge Models. [ABSTRACT FROM AUTHOR]

Iconic memory, the short-lasting visual memory of a briefly flashed stimulus, is an important component of most models of visual perception. Here we investigate what physiological mechanisms underlie this capacity by showing rapid serial visual presentation (RSVP) sequences with and without interstimulus gaps to human observers and macaque monkeys. For gaps of up to 93 ms between consecutive images, human observers and neurones in the temporal cortex of macaque monkeys were found to continue processing a stimulus as if it was still present on the screen. The continued firing of neurones in temporal cortex may therefore underlie iconic memory. Based on these findings, a neurophysiological vision of iconic memory is presented. [ABSTRACT FROM AUTHOR]

Many object-related actions can be recognized both by their sound and by their vision. Here we describe a population of neurons in the ventral premotor cortex of the monkey that discharge both when the animal performs a specific action and when it hears or sees the same action performed by another individual. These 'audiovisual mirror neurons' therefore represent actions independently of whether these actions are performed, heard or seen. The magnitude of auditory and visual responses did not differ significantly in half the neurons. A neurometric analysis revealed that based on the response of these neurons, two actions could be discriminated with 97% accuracy. [ABSTRACT FROM AUTHOR]

Neurons in the anterior regions of the banks of the superior temporal sulcus (STSa) of the macaque monkey respond to the sight of biologically significant stimuli such as faces, bodies and their motion. In this study the responses of STSa neurons were recorded during the gradual occlusion of the experimenter and other mobile objects behind screens at distances of 0.5–4 m from the monkeys. The experimenter or other object remained out of sight for 3–15 s before emerging back in to view. We describe a population of neurons (n=33) showing increased activity during the occlusion of objects that was maintained for up to 11 s following complete occlusion (when only the occluder itself was visible). This increase in activity was selective for the position of the occlusion within the testing room. Many neurons showed little or no change in activity prior to occlusion when the object or experimenter was completely in view. By coding for the presence and location of recently occluded objects, these responses may contribute to the perceptual capacity for object permanence. [ABSTRACT FROM AUTHOR]

Macaque monkeys were presented with continuous rapid serial visual presentation (RSVP) sequences of unrelated naturalistic images at rates of 14–222 msec/image, while neurons that responded selectively to complex patterns (e.g., faces) were recorded in temporal cortex. Stimulus selectivity was preserved for 65% of these neurons even at surprisingly fast presentation rates (14 msec/image or 72 images/sec). Five human subjects were asked to detect or remember images under equivalent conditions. Their performance in both tasks was above chance at all rates (14–111 msec/image). The performance of single neurons was comparable to that of humans and responded in a similar way to changes in presentation rate. The implications for the role of temporal cortex cells in perception are discussed. [ABSTRACT FROM AUTHOR]

Abstract Rationale: Whether the underlying neurochemical basis of sensori(motor) gating is exclusively the result of mammalian brain evolution is not known. Objective: The effects of ketamine (KET), benztropine (BTP), apomorphine (APO), methylphenidatehydrochloride (AMP) and haloperidol (HAL) on sensorimotor gating of the acoustic startle and gating of auditory input into the telelencephalon was assessed in a within-subject design in pigeons (Columba livia) using the prepulse inhibition (PPI) paradigm. Methods: The startle blink reflex was recorded using EMG electrodes which were chronically implanted into the adjoining Musculus palpepralis superior et inferior, Musculus elevator palpebralis superior, and Musculus nictitantis. Thalamic gating was recorded using electrodes which were chronically implanted into the nucleus ovoidalis thalami and the neostriatum caudale (field L), respectively. Results: KET, APO and AMP disrupted dose-dependently sensorimotor gating. The effect of APO and AMP was blocked by HAL. PPI disruption following BTP did not reach statistical significance. KET disrupted thalamic gating and increased prepulse-induced inhibition in field L. By contrast, AMP increased thalamic and decreased field L inhibition of field potentials when preceded by a pre-stimulus. Both effects were antagonised by HAL thus providing preliminary evidence for a D[sub 2]-mediated auditory gating mechanism in the thalamus. However, while the effect of APO at the thalamic level was similar to AMP, prepulse-induced inhibition of field L activity was enhanced. This may be explained by concurrent D[sub 1]-mediated telencephalic inhibition. Conclusion: It is concluded that thalamic gating is modulated by a dopaminergic/glutamatergic mechanism. The findings also confirm the notion of an homologous neurochemical basis of... [ABSTRACT FROM AUTHOR]