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  • #31
    Yes,

    I saw the PLOS paper. It is fairly close to home for me as I have a family member who takes on short term contracts and always gets short listed when his CV is read by a person, but can't get onto shortlists selected by algorithm.

    Diagnostic algorithms may have holes in them, which can be disastrous when hard pressed clinicians go into robot mode. Decades ago when I was carrying a respiratory bleep, I spent almost a minute listening for breath sounds before I realised that the patient was deceased. I was incredibly pressed for time, but no excuse.
    Jo Bowyer
    Chartered Physiotherapist Registered Osteopath.
    "Out beyond ideas of wrongdoing and rightdoing,there is a field. I'll meet you there." Rumi

    Comment


    • #32
      Mnemonic Training Reshapes Brain Networks to Support Superior Memory

      http://www.cell.com/neuron/fulltext/...273(17)30087-9

      Highlights

      •Memory champions show distributed functional brain network connectivity changes

      •Mnemonic strategies for superior memory can be learned by naive subjects

      •Mnemonic training induces similarity with memory champion brain connectivity

      •Brain network dynamics of this effect differ between task and resting state
      Summary
      Memory skills strongly differ across the general population; however, little is known about the brain characteristics supporting superior memory performance. Here we assess functional brain network organization of 23 of the world’s most successful memory athletes and matched controls with fMRI during both task-free resting state baseline and active memory encoding. We demonstrate that, in a group of naive controls, functional connectivity changes induced by 6 weeks of mnemonic training were correlated with the network organization that distinguishes athletes from controls. During rest, this effect was mainly driven by connections between rather than within the visual, medial temporal lobe and default mode networks, whereas during task it was driven by connectivity within these networks. Similarity with memory athlete connectivity patterns predicted memory improvements up to 4 months after training. In conclusion, mnemonic training drives distributed rather than regional changes, reorganizing the brain’s functional network organization to enable superior memory performance.
      Junior doctors used to be able to do this. I remember someone writing an entire page from a textbook on Parkinsons Disease for me from memory, I wonder if the current generation can do this.

      Surgical trainees can still draw beautifully




      Only Three Fingers Write, but the Whole Brain Works†: A High-Density EEG Study Showing Advantages of Drawing Over Typing for Learning

      http://journal.frontiersin.org/artic...017.00706/full

      Are different parts of the brain active when we type on a keyboard as opposed to when we draw visual images on a tablet? Electroencephalogram (EEG) was used in young adults to study brain electrical activity as they were typing or describing in words visually presented PictionaryTM words using a keyboard, or as they were drawing pictures of the same words on a tablet using a stylus. Analyses of temporal spectral evolution (time-dependent amplitude changes) were performed on EEG data recorded with a 256-channel sensor array. We found that when drawing, brain areas in the parietal and occipital regions showed event related desynchronization activity in the theta/alpha range. Existing literature suggests that such oscillatory neuronal activity provides the brain with optimal conditions for learning. When describing the words using the keyboard, upper alpha/beta/gamma range activity in the central and frontal brain regions were observed, especially during the ideation phase. However, since this activity was highly synchronized, its relation to learning remains unclear. We concluded that because of the benefits for sensory-motor integration and learning, traditional handwritten notes are preferably combined with visualizations (e.g., small drawings, shapes, arrows, symbols) to facilitate and optimize learning.
      Introduction
      The general effectiveness of notetaking in educational settings is well-documented, but the evidence mainly stems from a time when laptop use in classrooms was not very common. Previous research has focused on how encoding affects learning (e.g., Kiewra, 1989). The encoding hypothesis proposes that the processing that occurs during notetaking enhances recall and retention. Notetaking can be generative (e.g., summarizing, reframing, paraphrasing) or non-generative (i.e., verbatim transcribing). Verbatim notetaking typically involves relatively shallow cognitive processing (Craik and Lockhart, 1972; Kiewra, 1985). Greater encoding benefits have been observed the more deeply information is processed during notetaking (DiVesta and Gray, 1973). Studies have shown that non-verbatim notetaking leads to better performance than verbatim notetaking, especially on conceptual items (Aiken et al., 1975; Bretzing and Kulhavy, 1979; Slotte and Lonka, 1999; Igo et al., 2005). Traditional laptop use, using the keyboard, promotes verbatim transcription of lecture content because most students can type much faster than they can write (Brown, 1988). Thus, typing may undermine the encoding benefits seen in past notetaking studies.
      09/05/2017
      Last edited by Jo Bowyer; 09-05-2017, 10:27 PM.
      Jo Bowyer
      Chartered Physiotherapist Registered Osteopath.
      "Out beyond ideas of wrongdoing and rightdoing,there is a field. I'll meet you there." Rumi

      Comment


      • #33
        Potentiation of motor sub-networks for motor control but not working memory: Interaction of dACC and SMA revealed by resting-state directed functional connectivity

        http://journals.plos.org/plosone/art...l.pone.0172531

        Abstract

        The dorsal Anterior Cingulate Cortex (dACC) and the Supplementary Motor Area (SMA) are known to interact during motor coordination behavior. We previously discovered that the directional influences underlying this interaction in a visuo-motor coordination task are asymmetric, with the dACC→SMA influence being significantly greater than that in the reverse direction. To assess the specificity of this effect, here we undertook an analysis of the interaction between dACC and SMA in two distinct contexts. In addition to the motor coordination task, we also assessed these effects during a (n-back) working memory task. We applied directed functional connectivity analysis to these two task paradigms, and also to the rest condition of each paradigm, in which rest blocks were interspersed with task blocks. We report here that the previously known asymmetric interaction between dACC and SMA, with dACC→SMA dominating, was significantly larger in the motor coordination task than the memory task. Moreover the asymmetry between dACC and SMA was reversed during the rest condition of the motor coordination task, but not of the working memory task. In sum, the dACC→SMA influence was significantly greater in the motor task than the memory task condition, and the SMA→dACC influence was significantly greater in the motor rest than the memory rest condition. We interpret these results as suggesting that the potentiation of motor sub-networks during the motor rest condition supports the motor control of SMA by dACC during the active motor task condition.
        Introduction

        How are brain networks potentiated for action? As with the muscles in the body, the potential for dynamics in the brain may be encoded in the relationship between the system’s rest state and its active state. This relationship has been extensively discussed in terms of the metabolic demands of the brain in both rest and task-active states, particularly from the perspective of the fMRI signal [1]. The explosion of interest in resting-state fMRI signals can in part be traced to these initial theoretical discussions. Nevertheless, much of resting-state fMRI (rsfMRI) research has been driven by the search for understanding default mode function in the brain [2], or in discovering network structure from spontaneous fluctuations in the fMRI signal [3, 4]. In large part, these initiatives have uncovered general structural constraints driving rsfMRI fluctuations that are spontaneous, induced by physiological stimulation [5], or constrained by task-active processing [6]. Yet, a parallel literature continues to investigate resting-state connectivity and its relationship to network function in the task-active state [7, 8]. These investigations indicate that functional connectivity between networks in the rest state, is predictive of the same in the task state [9].


        Is “Allostasis” The Brain’s Essential Function?......By Neuroskeptic May 5, 2017

        http://blogs.discovermagazine.com/ne.../#.WQ-RaojysdV

        A paper just published in Nature Human Behaviour makes some big claims about the brain. It’s called Evidence for a large-scale brain system supporting allostasis and interoception in humans, but how much is evidence and how much is speculation?

        The authors, Ian R. Kleckner and colleagues of Northeastern University, argue that a core function of the brain is allostasis, which they define as the process by which the brain “efficiently maintains energy regulation in the body”. Allostasis entails “anticipating the body’s energy needs [and] preparing to meet those needs before they arise.” Kleckner et al. point to “physical movements to cool the body’s temperature before it gets too hot” as one example of allostasis.

        A concept closely related to allostasis is interoception, the process by which the brain receives information about the body’s internal state from sensory nerves inside the body.
        There is a buzz around this paper at the moment. It's worth reading what NeuroSkeptic has to say and the comments following his piece.

        Update 07/05/2017
        Last edited by Jo Bowyer; 08-05-2017, 12:45 AM.
        Jo Bowyer
        Chartered Physiotherapist Registered Osteopath.
        "Out beyond ideas of wrongdoing and rightdoing,there is a field. I'll meet you there." Rumi

        Comment


        • #34
          Shaping visual space perception through bodily sensations: Testing the impact of nociceptive stimuli on visual perception in peripersonal space with temporal order judgments


          http://journals.plos.org/plosone/art...l.pone.0182634


          Abstract


          Coordinating spatial perception between body space and its external surrounding space is essential to adapt behaviors to objects, especially when they are noxious. Such coherent multisensory representation of the body extended into external space is conceptualized by the notion of peripersonal reference frame, mapping the portion of space in which somatic and extra-somatic inputs interact closely. Studies on crossmodal interactions between nociception and vision have been scarce. Here we investigated how the perception of visual stimuli, especially those surrounding the body, can be impacted by a nociceptive and potentially harmful stimulus inflicted on a particular body part. In two temporal order judgment tasks, participants judged which of two lateralized visual stimuli, presented either near or far from the body, had been presented first. Visual stimuli were preceded by nociceptive stimuli, either applied unilaterally (on one single hand) or bilaterally (on both hands simultaneously). In Experiment 1 participants’ hands were always placed next to the visual stimuli presented near the trunk, while in Experiment 2 they could also be placed next to the visual stimuli presented far from the trunk. In Experiment 1, the presence of unilateral nociceptive stimuli prioritized the perception of visual stimuli presented in the same side of space as the stimulated hand, with a significantly larger effect when visual stimuli were presented near the body than when presented farther away. Experiment 2 showed that these visuospatial biases were related to the spatial congruency between the hand on which nociceptive stimuli were applied and the visual stimuli, independently of the relative distance of both the stimulated hand and the visual stimuli from the trunk. Indeed, nociceptive stimuli mostly impacted the perception of the closest visual stimuli. It is hypothesized that these crossmodal interactions may rely on representations of the space directly surrounding specific body parts.
          1. Introduction


          For any living organism, it is important to monitor the space surrounding the body in order to avoid stimuli that have the potential to inflict damage on the body. Pain represents the archetype of physical threat. It is an unpleasant sensory and emotional experience that acts as a warning signal about potential body damage, with the aim of triggering behaviors purposely oriented to defend or restore the physical integrity of the body. Pain is initiated, in normal conditions, by the activation of specific sensory receptors, the nociceptors, characterized by the ability to code high intensity, and, as a consequence, potentially harmful stimuli. In order to adapt the behavior to possibly harmful stimuli, we need to detect and localize the part of the body that is potentially being harmed, i.e. the body part on which the nociceptive stimulus is applied. The spatial position of sensory information can be coded according to different frames of reference, i.e. coordinate systems. Localizing the position of a nociceptive stimulus depends partly on projections of spatially organized sensory receptor fields on the body surface to specific spatially segregated groups of neurons in the cortex [14]. This somatotopic frame of reference, representing the skin surface anatomically, is however not sufficient to respond adequately to the potential threat. Localizing the position of the possibly harming object in external space is also of primary importance, in order to spatially guide defensive motor responses. It is therefore necessary to coordinate the representation and perception of the space of the body and its surrounding external space. Such a coherent multisensory representation of the body space and its surrounding space is conceptualized by the notion of peripersonal reference frames. The peripersonal reference frames are mapping systems coding the portion of space in which somatic and extra-somatic (e.g. visual) stimuli can interact closely [59]. The existence of peripersonal frames of reference has largely been documented for touch [1013], but very poorly investigated for nociception and pain [14]. However, studying the involvement of a peripersonal frame of reference in localizing nociceptive stimuli is not only important to apprehend how nociception is integrated with other sensory information to build a full representation of physical threats, but also to broaden the understanding of chronic pain pathophysiology. Indeed, it has recently been suggested that chronic pain can impair the representation and the perception of external space, although the exact nature of these impairments is still unknown [15].
          Jo Bowyer
          Chartered Physiotherapist Registered Osteopath.
          "Out beyond ideas of wrongdoing and rightdoing,there is a field. I'll meet you there." Rumi

          Comment


          • #35
            Harmonic Brain Modes: A Unifying Framework for Linking Space and Time in Brain Dynamics

            http://journals.sagepub.com/doi/abs/...r_pub%3dpubmed

            Abstract


            A fundamental characteristic of spontaneous brain activity is coherent oscillations covering a wide range of frequencies. Interestingly, these temporal oscillations are highly correlated among spatially distributed cortical areas forming structured correlation patterns known as the resting state networks, although the brain is never truly at “rest.” Here, we introduce the concept of harmonic brain modes—fundamental building blocks of complex spatiotemporal patterns of neural activity. We define these elementary harmonic brain modes as harmonic modes of structural connectivity; that is, connectome harmonics, yielding fully synchronous neural activity patterns with different frequency oscillations emerging on and constrained by the particular structure of the brain. Hence, this particular definition implicitly links the hitherto poorly understood dimensions of space and time in brain dynamics and its underlying anatomy. Further we show how harmonic brain modes can explain the relationship between neurophysiological, temporal, and network-level changes in the brain across different mental states (wakefulness, sleep, anesthesia, psychedelic). Notably, when decoded as activation of connectome harmonics, spatial and temporal characteristics of neural activity naturally emerge from the interplay between excitation and inhibition and this critical relation fits the spatial, temporal, and neurophysiological changes associated with different mental states. Thus, the introduced framework of harmonic brain modes not only establishes a relation between the spatial structure of correlation patterns and temporal oscillations (linking space and time in brain dynamics), but also enables a new dimension of tools for understanding fundamental principles underlying brain dynamics in different states of consciousness.

            https://www.somasimple.com/forums/fo...brain-dynamics
            Last edited by Jo Bowyer; 05-09-2017, 12:14 AM.
            Jo Bowyer
            Chartered Physiotherapist Registered Osteopath.
            "Out beyond ideas of wrongdoing and rightdoing,there is a field. I'll meet you there." Rumi

            Comment


            • #36
              Study reveals receptor movement is essential for synaptic plasticity as a response to neural activity.

              http://neurosciencenews.com/memory-m...-control-7502/
              Jo Bowyer
              Chartered Physiotherapist Registered Osteopath.
              "Out beyond ideas of wrongdoing and rightdoing,there is a field. I'll meet you there." Rumi

              Comment


              • #37
                Optimizing information processing in neuronal networks beyond critical states


                http://journals.plos.org/plosone/art...l.pone.0184367

                Abstract

                Critical dynamics have been postulated as an ideal regime for neuronal networks in the brain, considering optimal dynamic range and information processing. Herein, we focused on how information entropy encoded in spatiotemporal activity patterns may vary in critical networks. We employed branching process based models to investigate how entropy can be embedded in spatiotemporal patterns. We determined that the information capacity of critical networks may vary depending on the manipulation of microscopic parameters. Specifically, the mean number of connections governed the number of spatiotemporal patterns in the networks. These findings are compatible with those of the real neuronal networks observed in specific brain circuitries, where critical behavior is necessary for the optimal dynamic range response but the uncertainty provided by high entropy as coded by spatiotemporal patterns is not required. With this, we were able to reveal that information processing can be optimized in neuronal networks beyond critical states.
                Jo Bowyer
                Chartered Physiotherapist Registered Osteopath.
                "Out beyond ideas of wrongdoing and rightdoing,there is a field. I'll meet you there." Rumi

                Comment


                • #38
                  Highly Precise Wiring in the Cerebral Cortex

                  http://neurosciencenews.com/cerebral...x-wiring-7543/

                  A team of scientists around Moritz Helmstaedter at the Max Planck Institute for Brain Research in Frankfurt am Main and Helene Schmidt at the Bernstein-Center of Humboldt-University in Berlin have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

                  The researchers report that synapses in this region of the brain are sorted very precisely along the electrical cables of the nerve cells. The nerve cells establish an unexpectedly precise circuit motive, in which first so-called inhibitory nerve cells are contacted before in the next step the actual (excitatory) activation of the next nerve cell can be executed. This motif of nerve cell “trios” can be considered a core connectivity motif in this type of cortex. Scientists speculate that such a highly precise circuit motive could be used for computing hypotheses about the next step in space.
                  In the current study, the scientists looked at these circuits in more detail and found that, contrary to prior belief, the synapses, i.e. contacts other nerve cells, are exceptionally precisely positioned. Within an extremely dense network of nerve cells (looking like a dense impenetrable forest, see attached figures), the nerve cells are in fact arranged in orderly triplets, in which a nerve cell first activates an inhibitory nerve cell. Transfer of the signal to the next excitatory nerve cell can however be hindered by the veto of the inhibitory nerve cell.
                  medial-entorhinal-cortex-neuron-neurosciencenews.jpg?w=750.jpg

                  The dense neuronal network of the medial entorhinal cortex (neuronal cables in grey) and the surprisingly precise pattern of synapses found in this part of the brain shown in colour. NeuroscienceNews.com image is credited to MPI f. Brain Research.
                  This core circuit, more or less functioning like a cortical transistor, would be able to propagate information in a very selective way, for instance only when additional information about the context and the surrounding of the animal or the human is available. The nerve cells within this transistor apparently use the very precise positioning of contact sites along their electrically conducting nerve cell cables (so-called axons). “While many consider the cerebral cortex as a randomly assembled web of nerve cells and have already turned to simulating this random network, we now discover an extremelyprecise connectivity pattern. In the cerebral cortex, taking a much closer look is clearly worth it”, according to Helmstaedter.
                  Jo Bowyer
                  Chartered Physiotherapist Registered Osteopath.
                  "Out beyond ideas of wrongdoing and rightdoing,there is a field. I'll meet you there." Rumi

                  Comment


                  • #39
                    Brain wiring affects how people perform specific tasks

                    https://www.sciencedaily.com/release...1005102618.htm

                    The brain is organized into different subnetworks, or "modules," that support distinct functions for different tasks, such as speaking, memorizing and expressing emotion. The researchers examined how high or low brain modularity -- the degree to which the modules communicate with one another -- impacts performance of simple and complex tasks.

                    "Think of your brain as you would think of a university," said Simon Fischer-Baum, an assistant professor of psychology in Rice's School of Social Sciences and one of the study's authors. "Individuals organize themselves into densely interconnected communities, like the dormitories and sports teams, though individuals within these groups also have connections with people outside of those groups. Brains are the same way: Brain regions are organized into communities with lots of connections between regions in the community and fewer connections to regions outside of the community. But people's brains are different. Some people have brains that are better described as having rigid community structure -- or higher modularity -- while other people have brains without such rigid community structure -- or lower modularity."

                    Throughout the course of the study, modularity was measured on a scale from zero to one. Zero represented low modularity -- brains in which every region of the brain is just as likely to communicate with any other region; one represented high modularity -- brains that can be divided into communities of brain regions whose members only communicate with each other.

                    In the study, the researchers had 52 participants (16 men, 36 women) between the ages of 18 and 26 undergo functional magnetic resonance imaging (fMRI), a process that measures brain neural activity by detecting changes associated with blood oxygen levels. The neural activity of each participant was studied by fMRI for 21 minutes while they were at rest. If neural activity increased and decreased in two areas at the same time over the course of the scan, it was an indicator that the two areas were connected. Using these data to measure which brain areas were connected to each other, the researchers determined the extent to which participants' brains could be described as having communities of brain regions that communicate only with each other.

                    The researchers then took the participants through a series of behavioral tasks, including complex tasks that tested their memory while simultaneously doing simple arithmetic and simple tasks such as indicating the direction an arrow was pointing when their attention had been already drawn to the location the arrow would appear.

                    The researchers found that participants with high-modularity brains were more successful at performing simple tasks than individuals with low-modularity brains. In the experiment measuring reaction time to the arrows, individuals with high modularity performed nearly twice as successfully (a reaction time advantage of 58 milliseconds for knowing where the target would appear) as individuals with low modularity (34 milliseconds advantage).

                    However, participants with low-modularity brains had greater success with complex tasks than participants with high-modularity brains. For example, those with low modularity correctly recalled 86 percent of the items in the memory task, while individuals with high modularity correctly recalled only 76 percent.

                    Fischer-Baum said that this effect can be considered relative to the decline in working memory with age, which is a hallmark of the cognitive effects of aging. Based on previous research, this difference in memory recall between the high- and low-modularity subgroups of highly educated, healthy young adults is roughly equivalent to the difference between memory recall at age 20 and at age 70.
                    Jo Bowyer
                    Chartered Physiotherapist Registered Osteopath.
                    "Out beyond ideas of wrongdoing and rightdoing,there is a field. I'll meet you there." Rumi

                    Comment


                    • #40
                      Henry Markram Talks Brain Simulation

                      The preliminary work for simulating the human brain is already under way

                      Artificial intelligence is progressing rapidly, and its impact on our daily lives will only increase. Today, there are still many things humans can do that computers can’t. But will it always be that way? Should we worry about a future in which the capabilities of machines rival those of humans across the board? For IEEE Spectrum’s June 2017 special issue, we asked a range of technologists and visionaries to weigh in on what the future holds for AI and brainlike computing.

                      When will we have computers as capable as the brain?

                      The brain is an infinite-dimensional network of networks of genes, proteins, cells, synapses, and brain regions, all operating in a dynamically changing cocktail of neurochemicals. Our perceptions and movements, thoughts and feelings emerge as electrical, chemical, and mechanical chain reactions explode and weave through these networks. Because there is no scientific evidence that we can ignore any of these reactions, the only way to get close to the capabilities of the brain is to simulate or emulate all of them. When that will happen depends on the level of resolution that we need to capture all these reactions.

                      Let’s not speculate when we’ll be able to simulate every single molecule in all its possible states or assume that a coarse-grained simulation, where molecules are simulated in groups, would have enough resolution to capture the brain’s reactions. To simulate the human brain at that resolution, we would need supercomputers on the yotta scale, with a million times more computing power than the exascale machines now on the horizon. A mouse brain would need a zettascale computer, and a lobster brain would need exascale. Today’s petascale computers are just enough for a coarse-grained simulation of a worm, like Rotifera.
                      https://spectrum.ieee.org/robotics/a...ain-simulation
                      Marcel

                      "Evolution is a tinkerer not an engineer" F.Jacob
                      "Without imperfection neither you nor I would exist" Stephen Hawking

                      Comment


                      • #41
                        Should we be afraid of AI?

                        https://www.somasimple.com/forums/fo...864#post386864

                        But will it always be that way? Should we worry about a future in which the capabilities of machines rival those of humans across the board?
                        Doesn't appear to be an immanent threat unless one gets upset about losing at chess, or Go.
                        Last edited by Jo Bowyer; 08-11-2017, 07:29 PM.
                        Jo Bowyer
                        Chartered Physiotherapist Registered Osteopath.
                        "Out beyond ideas of wrongdoing and rightdoing,there is a field. I'll meet you there." Rumi

                        Comment


                        • marcel
                          marcel commented
                          Editing a comment
                          Seems that the thing that Microsoft introduced: "Tay" just before they took it offline, in a way reflect things that go on in certain groups (of humans) worldwide.

                        • Jo Bowyer
                          Jo Bowyer commented
                          Editing a comment
                          One of the comments I read thought that it was unwise to design Tay as a teenage female, which they did in order to make it more user friendly. Unfortunately, that didn't prevent it from becoming a Nazi, it just soaked up everything fed to it and regurgitated a precis.

                      • #42
                        Network Neuroscience Theory of Human Intelligence

                        http://www.cell.com/trends/cognitive...613(17)30221-8

                        An enduring aim of research in the psychological and brain sciences is to understand the nature of individual differences in human intelligence, examining the stunning breadth and diversity of intellectual abilities and the remarkable neurobiological mechanisms from which they arise. This Opinion article surveys recent neuroscience evidence to elucidate how general intelligence, g, emerges from individual differences in the network architecture of the human brain. The reviewed findings motivate new insights about how network topology and dynamics account for individual differences in g, represented by the Network Neuroscience Theory. According to this framework, g emerges from the small-world topology of brain networks and the dynamic reorganization of its community structure in the service of system-wide flexibility and adaptation.
                        Jo Bowyer
                        Chartered Physiotherapist Registered Osteopath.
                        "Out beyond ideas of wrongdoing and rightdoing,there is a field. I'll meet you there." Rumi

                        Comment

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