Weekly Papers on Philosophy of Mind (38)

Abstract

Tony Chemero advances the radical thesis that cognition and consciousness are actually the same thing. I question this conclusion. Even if we are the brain–body environmental synergies that Chemero and others claim, we will not be able to conclude that consciousness is just cognition because this view actually expands cognition beyond being the sort of natural kind upon which to hook phenomenal experience. Identifying consciousness with cognition either means consciousness exists at multiple levels of organization in the universe, or more work needs to be done to delineate conscious cognition from other synergies. Still, while radical embodied cognition does not solve any of the hard problems associated with consciousness, this perspective allows useful insights concerning phenomenal experience. Moreover, recent neuropsychological research in action selection and projection can help us refine notions of consciousness from this embodied perspective.

Awareness can be part of it, but it’s much more than that-- Read more on ScientificAmerican.com

There’s no central government database on police-related shootings in the US, but now a machine-learning system is helping record details by scanning the news
A true AI revolution can't happen without a re-engineering of how business organizations operate -- Read more on ScientificAmerican.com

      

Abstract

In believing or acting on authority, an agent appears to believe or act without making up her own mind about what is the case or what to do. How is this possible? How can an agent make up her mind about a theoretical or practical question, and so believe or act intentionally, without doing so for herself? This paper argues that the standard account available in the literature of how it is that an agent can make up her mind without doing so for herself, an account framed in terms of Joseph Raz’s notion of preemptive reasons, fails to adequately distinguish our rational dependence on other agents from reliance on ordinary instruments. It then offers an alternative account of what it is to make up one’s mind without doing so for oneself, one that focuses on the way in which the kind of rational responsibility that accrues to instances of settling a theoretical or practical question can be interpersonally distributed between agents and authorities.

Awe is so powerful it alters your sense of self, connects you with humanity and boosts your mind and body. And there's a surprising way to get more of it
Order a coffee, type an email or learn a new instrument faster. Mind-reading tech is now so advanced that all this and more is within reach with thought alone
Statues: researchers to mind their history Nature 549, 7672 (2017). doi:10.1038/549334b Authors: Evelynn M. Hammonds & Susan M. Reverby Your Editorial created one more flashpoint in the current US debate about Confederate monuments (see Nature549, 5–6; 10.1038/549005b2017 and Naturehttp://doi.org/ccvm; 2017).The concern is what kind of history we memorialize in the statues of J.

Abstract

Deception has long been an important topic in philosophy (see Augustine in Treatises on various subjects, New York, Fathers of the Church, 1952; Kant in Practical philosophy, Cambridge University Press, Cambridge,1996; Chisholm and Feehan in J Philos 74: 143–159, 1977; Mahon in Int J Appl Philos 21: 181–194, 2007; Carson in Lying and deception, Oxford University Press, New York, 2010). However, the traditional analysis of the concept, which requires that a deceiver intentionally cause her victim to have a false belief, rules out the possibility of much deception in the animal kingdom. Cognitively unsophisticated species, such as fireflies and butterflies, have simply evolved to mislead potential predators and/or prey. To capture such cases of “functional deception,” several researchers (e.g., Sober, From a biological point of view, Cambridge University Press, Cambridge, 1994; Hauser in: Whiten, Byrne (eds) Machiavellian intelligence II, Cambridge University Press, Cambridge, pp 112–143, 1997; Searcy and Nowicki, The evolution of animal communication, Princeton University Press, Princeton, 2005; Skyrms, Signals, Oxford University Press, Oxford 2010) have endorsed the broader view that deception only requires that a deceiver benefit from sending a misleading signal. Moreover, in order to facilitate game-theoretic study of deception in the context of Lewisian sender-receiver games, Brian Skyrms has proposed an influential formal analysis of this view. Such formal analyses have the potential to enhance our philosophical understanding of deception in humans as well as animals. However, as we argue in this paper, Skyrms’s analysis, as well as two recently proposed alternative analyses (viz., Godfrey-Smith in Review of signals: evolution, learning, and information by Brian Skyrms, Mind, 120: 1288–1297, 2001; McWhirter in Brit J Philos Sci 67: 757–780,2016), are seriously flawed and can lead us to draw unwarranted conclusions about deception.

Abstract

Ernest Sosa’s Judgment and Agency marks an important change from his earlier work in epistemology. While belief was at the center of his earlier approach to epistemological issues, a far more sophisticated mental state, judgment, plays the central role here. This paper examines the significance of this change in focus, and argues that there is reason to favor the earlier belief-centered approach over this new judgment-centered account.

Abstract

The grounding or motivating intuitions behind internalism and externalism seem to be fundamentally at odds. If there is ever to be a viable or satisfying solution to the problem, it must satisfy the grounding intuitions behind both sides of the debate. Duncan Pritchard claims his theory of epistemological disjunctivism (ED) does just this, arguing that it could be the holy grail we have all been waiting for. However, I believe the holy grail is already out there in the form of the theory that knowledge is a mental state (KMS). In this article, I defend the idea the KMS is far better able to satisfy the internalist and externalist intuitions than ED.

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Abstract

Imitative stimuli presented from a first-person perspective (FPP) produce stronger visuomotor effects than those presented from a third-person perspective (TPP) due to the relatively greater response of the mirror neuron system (MNS) to FPP stimuli. Some previous studies utilizing TPP stimuli have reported no differences in MNS activity between moving and static bodies’ stimuli. However, few studies have compared visuomotor effects of such stimuli when presented in the FPP. To clarify this issue, we measured cortical activation in 17 participants during a functional magnetic resonance imaging (MRI) imitation task involving three conditions: moving (a lifting finger was presented), static (an “X” appeared on a static finger), and control (an “X” appeared on a button). All stimuli were presented from the FPP or TPP. Participants were asked to lift the finger corresponding to the imitative stimulus. In the FPP condition, moving stimuli elicited greater MNS activation than static stimuli. Furthermore, such movement effects were stronger in the MNS and insula (a region associated with body-ownership) for FPP stimuli than for TPP stimuli. Psychophysiological interaction analysis revealed increased connectivity between the MNS and insula for moving stimuli in the FPP condition. These findings suggest that bodily movements presented in the FPP elicit a greater visuomotor response than static body presented in the FPP, and that the visuomotor effects of bodily movements were greater in the FPP condition than in the TPP condition. Our analyses further indicated that such responses are processed via the neural system underlying body-ownership. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.
APOE4 is the strongest genetic risk factor for late-onset Alzheimer disease. ApoE4 increases brain amyloid-β pathology relative to other ApoE isoforms. However, whether APOE independently influences tau pathology, the other major proteinopathy of Alzheimer disease and other tauopathies, or tau-mediated neurodegeneration, is not clear. By generating P301S tau transgenic mice on either a human ApoE knock-in (KI) or ApoE knockout (KO) background, here we show that P301S/E4 mice have significantly higher tau levels in the brain and a greater extent of somatodendritic tau redistribution by three months of age compared with P301S/E2, P301S/E3, and P301S/EKO mice. By nine months of age, P301S mice with different ApoE genotypes display distinct phosphorylated tau protein (p-tau) staining patterns. P301S/E4 mice develop markedly more brain atrophy and neuroinflammation than P301S/E2 and P301S/E3 mice, whereas P301S/EKO mice are largely protected from these changes. In vitro, E4-expressing microglia exhibit higher innate immune reactivity after lipopolysaccharide treatment. Co-culturing P301S tau-expressing neurons with E4-expressing mixed glia results in a significantly higher level of tumour-necrosis factor-α (TNF-α) secretion and markedly reduced neuronal viability compared with neuron/E2 and neuron/E3 co-cultures. Neurons co-cultured with EKO glia showed the greatest viability with the lowest level of secreted TNF-α. Treatment of P301S neurons with recombinant ApoE (E2, E3, E4) also leads to some neuronal damage and death compared with the absence of ApoE, with ApoE4 exacerbating the effect. In individuals with a sporadic primary tauopathy, the presence of an ε4 allele is associated with more severe regional neurodegeneration. In individuals who are positive for amyloid-β pathology with symptomatic Alzheimer disease who usually have tau pathology, ε4-carriers demonstrate greater rates of disease progression. Our results demonstrate that ApoE affects tau pathogenesis, neuroinflammation, and tau-mediated neurodegeneration independently of amyloid-β pathology. ApoE4 exerts a ‘toxic’ gain of function whereas the absence of ApoE is protective. Nature doi: 10.1038/nature24016
Nature Physics. doi:10.1038/nphys4257 Authors: Kush Paul, Parijat Sengupta, Eugene D. Ark, Haohua Tu, Youbo Zhao & Stephen A. Boppart Retinal-based opsins are light-sensitive proteins. The photoisomerization reaction of these proteins has been studied outside cellular environments using ultrashort tailored light pulses. However, how living cell functions can be modulated via opsins by modifying fundamental nonlinear optical properties of light interacting with the retinal chromophore has remained largely unexplored. We report the use of chirped ultrashort near-infrared pulses to modulate light-evoked ionic current from Channelrhodopsin-2 (ChR2) in brain tissue, and consequently the firing pattern of neurons, by manipulating the phase of the spectral components of the light. These results confirm that quantum coherence of the retinal-based protein system, even in a living neuron, can influence its current output, and open up the possibilities of using designer-tailored pulses for controlling molecular dynamics of opsins in living tissue to selectively enhance or suppress neuronal function for adaptive feedback-loop applications in the future.  bookmark  blog it  shared

Hundreds of circular RNAs (circRNAs) are highly abundant in the mammalian brain, often with conserved expression. Here we show that the circRNA Cdr1as is massively bound by the microRNAs (miRNAs) miR-7 and miR-671 in human and mouse brains. When the Cdr1as locus was removed from the mouse genome, knockout animals displayed impaired sensorimotor gating—a deficit in the ability to filter out unnecessary information—which is associated with neuropsychiatric disorders. Electrophysiological recordings revealed dysfunctional synaptic transmission. Expression of miR-7 and miR-671 was specifically and posttranscriptionally misregulated in all brain regions analyzed. Expression of immediate early genes such as Fos, a direct miR-7 target, was enhanced in Cdr1as-deficient brains, providing a possible molecular link to the behavioral phenotype. Our data indicate an in vivo loss-of-function circRNA phenotype and suggest that interactions between Cdr1as and miRNAs are important for normal brain function.

Ontogenetic studies help us understand the processes of evolutionary change. Previous studies on Neandertals have focused mainly on dental development and inferred an accelerated pace of general growth. We report on a juvenile partial skeleton (El Sidrón J1) preserving cranio-dental and postcranial remains. We used dental histology to estimate the age at death to be 7.7 years. Maturation of most elements fell within the expected range of modern humans at this age. The exceptions were the atlas and mid-thoracic vertebrae, which remained at the 5- to 6-year stage of development. Furthermore, endocranial features suggest that brain growth was not yet completed. The vertebral maturation pattern and extended brain growth most likely reflect Neandertal physiology and ontogenetic energy constraints rather than any fundamental difference in the overall pace of growth in this extinct human.

Ever walked into a room only to forget why you entered, accidentally called your boss “mum” or burst out laughing at bad news? Here's what's really going on

Correlation profiling of brain sub-cellular proteomes reveals co-assembly of synaptic proteins and subcellular distribution

Scientific Reports, Published online: 21 September 2017;doi:10.1038/s41598-017-11690-3

Abstract

Tony Chemero advances the radical thesis that cognition and consciousness are actually the same thing. I question this conclusion. Even if we are the brain–body environmental synergies that Chemero and others claim, we will not be able to conclude that consciousness is just cognition because this view actually expands cognition beyond being the sort of natural kind upon which to hook phenomenal experience. Identifying consciousness with cognition either means consciousness exists at multiple levels of organization in the universe, or more work needs to be done to delineate conscious cognition from other synergies. Still, while radical embodied cognition does not solve any of the hard problems associated with consciousness, this perspective allows useful insights concerning phenomenal experience. Moreover, recent neuropsychological research in action selection and projection can help us refine notions of consciousness from this embodied perspective.

Abstract

Exposure to acute stress induces multiple emotional responses, each with their own unique temporal dynamics. Dynamic functional connectivity (dFC) measures the temporal variability of network synchrony and captures individual differences in network neurodynamics. This study investigated the relationship between dFC and individual differences in emotions induced by an acute psychosocial stressor. Sixteen healthy adult women underwent fMRI scanning during a social evaluative threat (SET) task, and retrospectively completed questionnaires that assessed individual differences in subjectively experienced positive and negative emotions about stress and stress relief during the task. Group dFC was decomposed with parallel factor analysis (PARAFAC) into 10 components, each with a temporal signature, spatial network of functionally connected regions, and vector of participant loadings that captures individual differences in dFC. Participant loadings of two networks were positively correlated with stress-related emotions, indicating the existence of networks for positive and negative emotions. The emotion-related networks involved the ventromedial prefrontal cortex, cingulate cortex, anterior insula, and amygdala, among other distributed brain regions, and time signatures for these emotion-related networks were uncorrelated. These findings demonstrate that individual differences in stress-induced positive and negative emotions are each uniquely associated with large-scale brain networks, and suggest that dFC is a mechanism that generates individual differences in the emotional components of the stress response. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.

Abstract

Despite the evidence of altered white-matter tract property in individuals with autism spectrum disorder (ASD), little is known about their unaffected siblings. This study aimed to investigate white-matter integrity in unaffected siblings of ASD probands. Thirty-nine unaffected siblings (mean age 15.6 ± 6.0 years; 27 males, 69.2%) and 39 typically developing controls (TDC) (14.2 ± 5.6 years; 26 males, 66.7%) were assessed with diffusion spectrum images and neuropsychological tests. Using the tract-based automatic analysis and the threshold-free cluster weighted (TFCW) scores, we searched for the segments among 76 tracts with the largest difference over the entire brain compared to TDC. Tract integrity was quantified by calculating the mean generalized fractional anisotropy (mGFA) values of the segments with the largest difference in TFCW scores. Unaffected siblings showed reduced mGFA in the bilateral frontal aslant tracts, the right superior longitudinal fasciculus 2 (SLF2), the frontostriatal tracts from the right dorsolateral and left ventrolateral prefrontal cortices, the thalamic radiations of the left ventral and the right dorsal thalamus, the callosal fibers of the splenium, and the increased mGFA of the callosal fibers of the precuneus and the left inferior longitudinal fasciculus. Among these, reduced right SLF2 mGFA was associated with social awareness deficits; impaired frontostriatal tract was associated with internalizing problems, while right frontal aslant tract integrity was associated with visual memory deficits. In conclusion, unaffected siblings showed the aberrant integrity of several white-matter tracts, which were correlated with clinical symptoms and neurocognitive dysfunction. The altered tract integrity could be further examined in the probands with ASD. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.

Abstract

Children born very preterm (VP; <32 weeks' gestational age) are at risk for unfavorable outcomes in several cognitive domains, including spatial working memory (WM). The underlying neural basis of these cognitive impairments is poorly understood. We investigated differences in neuronal activation during spatial WM using a backward span (BS) task relative to a control (C) task in 45 VP children and 19 term-born controls aged 13 years. VP children showed significantly more activation in the bilateral superior frontal gyrus and significantly less activation in the left parahippocampal gyrus compared with controls. We further explored the distinct contributions of maintenance and manipulation processes of WM using forward span (FS)>C and BS > FS, respectively. There were no significant group differences in neuronal activation for FS > C. However, BS > FS revealed that VP children had significantly greater activation in the left middle frontal gyrus, in the left superior parietal gyrus and right cerebellar tonsil, and significantly less activation in the right precentral and postcentral gyrus and left insula compared with controls. Taken together these results suggest that VP children at 13 years of age show an atypical neuronal activation during spatial WM, specifically related to manipulation of spatial information in WM. It is unclear whether these findings reflect delayed maturation and/or recruitment of alternative neuronal networks as a result of neuroplasticity. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.

Abstract

Drawing from a common lexicon of semantic units, humans fashion narratives whose meaning transcends that of their individual utterances. However, while brain regions that represent lower-level semantic units, such as words and sentences, have been identified, questions remain about the neural representation of narrative comprehension, which involves inferring cumulative meaning. To address these questions, we exposed English, Mandarin, and Farsi native speakers to native language translations of the same stories during fMRI scanning. Using a new technique in natural language processing, we calculated the distributed representations of these stories (capturing the meaning of the stories in high-dimensional semantic space), and demonstrate that using these representations we can identify the specific story a participant was reading from the neural data. Notably, this was possible even when the distributed representations were calculated using stories in a different language than the participant was reading. Our results reveal that identification relied on a collection of brain regions most prominently located in the default mode network. These results demonstrate that neuro-semantic encoding of narratives happens at levels higher than individual semantic units and that this encoding is systematic across both individuals and languages. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.

Abstract

Sensory processing (i.e., the manner in which the nervous system receives, modulates, integrates, and organizes sensory stimuli) is critical when humans are deciding how to react to environmental demands. Although behavioral studies have shown that there are stable individual differences in sensory processing, the neural substrates that implement such differences remain unknown. To investigate this issue, structural magnetic resonance imaging scans were acquired from 51 healthy adults and individual differences in sensory processing were assessed using the Sensory Profile questionnaire (Brown et al.: Am J Occup Ther 55 (2001) 75–82). There were positive relationships between the Sensory Profile modality-specific subscales and gray matter volumes in the primary or secondary sensory areas for the visual, auditory, touch, and taste/smell modalities. Thus, the present results suggest that individual differences in sensory processing are implemented by the early sensory regions.Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.

Authors: Eiji Konishi

The quantum measurement scheme is suggested in two resonant models of quantum electrodynamics. The first model is the brain, where, for the propagation of its action potentials, the free electron laser-like coherence mechanism recently investigated by the author is applied. The second model is assembly of the Preparata coherence domains, in which we incorporate the quantum field theory of memory advocated by Umezawa et al. These two models are remarkably analogous.

Abstract

Imitative stimuli presented from a first-person perspective (FPP) produce stronger visuomotor effects than those presented from a third-person perspective (TPP) due to the relatively greater response of the mirror neuron system (MNS) to FPP stimuli. Some previous studies utilizing TPP stimuli have reported no differences in MNS activity between moving and static bodies’ stimuli. However, few studies have compared visuomotor effects of such stimuli when presented in the FPP. To clarify this issue, we measured cortical activation in 17 participants during a functional magnetic resonance imaging (MRI) imitation task involving three conditions: moving (a lifting finger was presented), static (an “X” appeared on a static finger), and control (an “X” appeared on a button). All stimuli were presented from the FPP or TPP. Participants were asked to lift the finger corresponding to the imitative stimulus. In the FPP condition, moving stimuli elicited greater MNS activation than static stimuli. Furthermore, such movement effects were stronger in the MNS and insula (a region associated with body-ownership) for FPP stimuli than for TPP stimuli. Psychophysiological interaction analysis revealed increased connectivity between the MNS and insula for moving stimuli in the FPP condition. These findings suggest that bodily movements presented in the FPP elicit a greater visuomotor response than static body presented in the FPP, and that the visuomotor effects of bodily movements were greater in the FPP condition than in the TPP condition. Our analyses further indicated that such responses are processed via the neural system underlying body-ownership. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.

APOE4 is the strongest genetic risk factor for late-onset Alzheimer disease. ApoE4 increases brain amyloid-β pathology relative to other ApoE isoforms. However, whether APOE independently influences tau pathology, the other major proteinopathy of Alzheimer disease and other tauopathies, or tau-mediated neurodegeneration, is not clear. By generating P301S tau transgenic mice on either a human ApoE knock-in (KI) or ApoE knockout (KO) background, here we show that P301S/E4 mice have significantly higher tau levels in the brain and a greater extent of somatodendritic tau redistribution by three months of age compared with P301S/E2, P301S/E3, and P301S/EKO mice. By nine months of age, P301S mice with different ApoE genotypes display distinct phosphorylated tau protein (p-tau) staining patterns. P301S/E4 mice develop markedly more brain atrophy and neuroinflammation than P301S/E2 and P301S/E3 mice, whereas P301S/EKO mice are largely protected from these changes. In vitro, E4-expressing microglia exhibit higher innate immune reactivity after lipopolysaccharide treatment. Co-culturing P301S tau-expressing neurons with E4-expressing mixed glia results in a significantly higher level of tumour-necrosis factor-α (TNF-α) secretion and markedly reduced neuronal viability compared with neuron/E2 and neuron/E3 co-cultures. Neurons co-cultured with EKO glia showed the greatest viability with the lowest level of secreted TNF-α. Treatment of P301S neurons with recombinant ApoE (E2, E3, E4) also leads to some neuronal damage and death compared with the absence of ApoE, with ApoE4 exacerbating the effect. In individuals with a sporadic primary tauopathy, the presence of an ε4 allele is associated with more severe regional neurodegeneration. In individuals who are positive for amyloid-β pathology with symptomatic Alzheimer disease who usually have tau pathology, ε4-carriers demonstrate greater rates of disease progression. Our results demonstrate that ApoE affects tau pathogenesis, neuroinflammation, and tau-mediated neurodegeneration independently of amyloid-β pathology. ApoE4 exerts a ‘toxic’ gain of function whereas the absence of ApoE is protective.

Nature doi: 10.1038/nature24016

Efforts to treat brain tumours by targeting cancer cells have had only modest clinical success. It emerges that targeting a protein secreted from neurons adjacent to the tumour might be a useful alternative approach.

Nature doi: 10.1038/nature24141

High-grade gliomas (HGG) are a devastating group of cancers, and represent the leading cause of brain tumour-related death in both children and adults. Therapies aimed at mechanisms intrinsic to glioma cells have translated to only limited success; effective therapeutic strategies will need also to target elements of the tumour microenvironment that promote glioma progression. Neuronal activity promotes the growth of a range of molecularly and clinically distinct HGG types, including adult and paediatric glioblastoma (GBM), anaplastic oligodendroglioma, and diffuse intrinsic pontine glioma (DIPG). An important mechanism that mediates this neural regulation of brain cancer is activity-dependent cleavage and secretion of the synaptic adhesion molecule neuroligin-3 (NLGN3), which promotes glioma proliferation through the PI3K–mTOR pathway. However, the necessity of NLGN3 for glioma growth, the proteolytic mechanism of NLGN3 secretion, and the further molecular consequences of NLGN3 secretion in glioma cells remain unknown. Here we show that HGG growth depends on microenvironmental NLGN3, identify signalling cascades downstream of NLGN3 binding in glioma, and determine a therapeutically targetable mechanism of secretion. Patient-derived orthotopic xenografts of paediatric GBM, DIPG and adult GBM fail to grow in Nlgn3 knockout mice. NLGN3 stimulates several oncogenic pathways, such as early focal adhesion kinase activation upstream of PI3K–mTOR, and induces transcriptional changes that include upregulation of several synapse-related genes in glioma cells. NLGN3 is cleaved from both neurons and oligodendrocyte precursor cells via the ADAM10 sheddase. ADAM10 inhibitors prevent the release of NLGN3 into the tumour microenvironment and robustly block HGG xenograft growth. This work defines a promising strategy for targeting NLGN3 secretion, which could prove transformative for HGG therapy.

Nature doi: 10.1038/nature24014

Aboozar Monavarfeshani, Courtney N. Knill, Ubadah Sabbagh, Jianmin Su, Michael A. Fox
Modelled on big physics projects, International Brain Lab will bring together pre-eminent neuroscientists to probe a single behavior-- Read more on ScientificAmerican.com

      

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Researchers unite in quest for ‘standard model’ of the brain

Nature 549, 7672 (2017).http://www.nature.com/doifinder/10.1038/549319a

Author: Alison Abbott

Modelled on big physics projects, the International Brain Lab will bring together some of the world’s pre-eminent neuroscientists to probe a single behaviour.

Modelled on big physics projects, the International Brain Lab will bring together some of the world’s pre-eminent neuroscientists to probe a single behaviour.

Nature 549 319 doi: 10.1038/549319a

Abstract

Network-sensitive neuroimaging methods have been used to characterize large-scale brain network degeneration in Alzheimers disease and its prodrome. However, few studies have investigated the combined effect of Alzheimers disease and cerebrovascular disease on brain network degeneration. Our study sought to examine the intrinsic functional connectivity and structural covariance network changes in 235 prodromal and clinical Alzheimers disease patients with and without cerebrovascular disease. We focused particularly on two higher-order cognitive networksthe default mode network and the executive control network. We found divergent functional connectivity and structural covariance patterns in Alzheimers disease patients with and without cerebrovascular disease. Alzheimers disease patients without cerebrovascular disease, but not Alzheimers disease patients with cerebrovascular disease, showed reductions in posterior default mode network functional connectivity. By comparison, while both groups exhibited parietal reductions in executive control network functional connectivity, only Alzheimers disease patients with cerebrovascular disease showed increases in frontal executive control network connectivity. Importantly, these distinct executive control network changes were recapitulated in prodromal Alzheimers disease patients with and without cerebrovascular disease. Across Alzheimers disease patients with and without cerebrovascular disease, higher default mode network functional connectivity z-scores correlated with greater hippocampal volumes while higher executive control network functional connectivity z-scores correlated with greater white matter changes. In parallel, only Alzheimers disease patients without cerebrovascular disease showed increased default mode network structural covariance, while only Alzheimers disease patients with cerebrovascular disease showed increased executive control network structural covariance compared to controls. Our findings demonstrate the differential neural network structural and functional changes in Alzheimers disease with and without cerebrovascular disease, suggesting that the underlying pathology of Alzheimers disease patients with cerebrovascular disease might differ from those without cerebrovascular disease and reflect a combination of more severe cerebrovascular disease and less severe Alzheimers disease network degeneration phenotype.

Abstract

Background

Source modeling of EEG traditionally relies on interplay between physiological hypotheses and mathematical estimates. We propose to optimize the process by using evidence gathered from brain imaging and intracortical recordings.

Methods

We recorded laser-evoked potentials in 18 healthy participants, using high-density EEG. Brain sources were modeled during the first second poststimulus, constraining their initial position to regions where nociceptive-related activity has been ascertained by intracranial EEG. These comprised the two posterior operculo-insular regions, primary sensorimotor, posterior parietal, anterior cingulate/supplementary motor (ACC/SMA), bilateral frontal/anterior insular, and posterior cingulate (PCC) cortices.

Results

The model yielded an average goodness of fit of 91% for individual and 95.8% for grand-average data. When compared with intracranial recordings from 27 human subjects, no significant difference in peak latencies was observed between modeled and intracranial data for 5 of the 6 assessable regions. Morphological match was excellent for operculo-insular, frontal, ACC/SMA and PCC regions (cross-correlation > 0.7) and fair for sensori-motor and posterior parietal cortex (c-c ∼ 0.5).

Conclusions

Multiple overlapping activities evoked by nociceptive input can be disentangled from high-density scalp EEG guided by intracranial data. Modeled sources accurately described the timing and morphology of most activities recorded with intracranial electrodes, including those coinciding with the emergence of stimulus awareness. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.

New way to catalogue the brain's cellular diversity may aid autism researchers-- Read more on ScientificAmerican.com

      

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In male mice, the same brain cells influence both aggressive and sexual behaviours, but for the first time we now know that's not the case for females
For the first time, language processing has been detected in areas of the brain that usually process vision, highlighting the organ’s extraordinary flexibility

Nature Physics. doi:10.1038/nphys4257

Authors: Kush Paul, Parijat Sengupta, Eugene D. Ark, Haohua Tu, Youbo Zhao & Stephen A. Boppart

Retinal-based opsins are light-sensitive proteins. The photoisomerization reaction of these proteins has been studied outside cellular environments using ultrashort tailored light pulses. However, how living cell functions can be modulated via opsins by modifying fundamental nonlinear optical properties of light interacting with the retinal chromophore has remained largely unexplored. We report the use of chirped ultrashort near-infrared pulses to modulate light-evoked ionic current from Channelrhodopsin-2 (ChR2) in brain tissue, and consequently the firing pattern of neurons, by manipulating the phase of the spectral components of the light. These results confirm that quantum coherence of the retinal-based protein system, even in a living neuron, can influence its current output, and open up the possibilities of using designer-tailored pulses for controlling molecular dynamics of opsins in living tissue to selectively enhance or suppress neuronal function for adaptive feedback-loop applications in the future.

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Migraine changes the way you experience the world all the time, not just during an attack. It's time for a new approach to treatment
From PhilPapers:
  1. Thought About Properties: Why the Perceptual Case is Basic.Dominic Alford-Duguid - forthcoming - Philosophical Quarterly.
    This paper defends a version of the old empiricist claim that to think about unobservable physical properties (such as spin or charge), a subject must be able to think perception-based thoughts about observable properties (such as red or circularity). The central argument builds upon foundations laid down by G. E. M. Anscombe and P. F. Strawson. It bridges the gap separating these foundations and the target claim by exploiting a neglected connection between thought about properties and our grasp of causation. (...)
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  2. Substitutive, Complementary and Constitutive Cognitive Artifacts: Developing an Interaction-Centered Approach.Marco Fasoli - forthcoming - Review of Philosophy and Psychology:1-17.
    AbtractTechnologies both new and old provide us with a wide range of cognitive artifacts that change the structure of our cognitive tasks. After a brief analysis of past classifications of these artifacts, I shall elaborate a new way of classifying them developed by focusing on an aspect that has been previously overlooked, namely the possible relationships between these objects and the cognitive processes they involve. Cognitive artifacts are often considered as objects that simply complement our cognitive capabilities, but this “complementary (...)
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Sep 21st 2017 GMT
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    A Psychologistic Theory of Metaphysical Explanation.Kristie Miller & James Norton - forthcoming - Synthese.

    Many think that sentences about what metaphysically explains what are true iff there exist grounding relations. This suggests that sceptics about grounding should be error theorists about metaphysical explanation. We think there is a better option: a theory of metaphysical explanation which offers truth conditions for claims about what metaphysically explains what that are not couched in terms of grounding relations, but are instead couched in terms of, inter alia, psychological facts. We do not argue that our account is superior (...)
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  2. Confidence as a Common Currency Between Vision and Audition.Vincent de GardelleFrancois Le Corre & Pascal Mamassian - 2016 - PLoS ONE 11 (1).
    The idea of a common currency underlying our choice behaviour has played an important role in sciences of behaviour, from neurobiology to psychology and economics. However, while it has been mainly investigated in terms of values, with a common scale on which goods would be evaluated and compared, the question of a common scale for subjective probabilities and confidence in particular has received only little empirical investigation so far. The present study extends previous work addressing this question, by showing that (...)
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Sep 19th 2017 GMT
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    The Role of Ontogeny in the Evolution of Human Cooperation.Michael Tomasello & Ivan Gonzalez-Cabrera - 2017 - Human Nature 28 (3):274–288.

    To explain the evolutionary emergence of uniquely human skills and motivations for cooperation, Tomasello et al. (2012, in Current Anthropology 53(6):673–92) proposed the interdependence hypothesis. The key adaptive context in this account was the obligate collaborative foraging of early human adults. Hawkes (2014, in Human Nature 25(1):28–48), following Hrdy (Mothers and Others, Harvard University Press, 2009), provided an alternative account for the emergence of uniquely human cooperative skills in which the key was early human infants’ attempts to solicit care and (...)
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Sep 18th 2017 GMT
  1.  

    Counterfeiting Perceptual Experience. Scepticism, Internalism, and the Disjunctive Conception of Experience.Tommaso Piazza - 2016 - Journal of Consciousness Studies 23 (7/8):100-131.

    Along with what McDowell has called the disjunctive conception of experience (DCE), and against a venerable tradition, the veridical experience that P and the subjectively indistinguishable hallucination that P are not type-identical mental states. According to McDowell, a powerful motivation for DCE is that it makes available the sole internalistically acceptable way out of a sceptical argument targeting the possibility of perceptual knowledge. In this paper I state in explicit terms the sceptical argument McDowell worries about, and show that DCE (...)
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  2. Being Somewhere. Egocentic Spatial Representation as Self-Representation.Ferdinand Pöhlmann - 2017 - Stuttgart: J.B. Metzler.
    Ferdinand Pöhlmann argues that a sense of one’s own basic abilities to move is a constitutive condition on the ability to perceive the world spatially. This constitutive relation explains why egocentric spatial representation is to be regarded as a kind of self-representation. In arguing for these claims, conceptual as well as empirical questions are discussed and an overview of accounts that take action as a constitutive condition on spatial representation is given. The picture that emerges is linked to the phenomenological (...)
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Sep 17th 2017 GMT
  1.  

    Sound and Image.Mark Eli Kalderon - forthcoming - In Christoph Limbeck & Friedrich Stadler (eds.), Publications of the Austrian Ludwig Wittgenstein Society. De Gruyter.

    We hear sounds, and their sources, and their audible qualities. Sounds and their sources are essentially dynamic entities, not wholly present at any given moment, but unfolding through their temporal interval. Sounds and their sources, essentially dynamic entities, are the bearers or susbtrata of audible qualities. Audible qualities are qualities essentially sustained by activity. The only bearers of audible qualities present in auditory experience are essentially dynamic entities. Bodies are not, in this sense, essentially dynamic entities and so are not (...)
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