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This paper explains the absence of the problem of other minds in ancient philosophy and links its rise in early modern philosophy with the distinction between primary and secondary qualities and the consequent veil of ideas. The futile struggles of early modern philosophers with the problems is delineated. So too are the incoherent theories of modern neuroscientists and psychologists. The sources of the manifold confusions are pinned down to use and misuse of the concept of mind, to misunderstandings about the nature of the human ability to say how things are subjectively with oneself, to misconstruals of the nature of introspection and self‐knowledge, and to the misguided picture of the "inner" and the "outer". Philosophical misunderstandings about knowledge of other minds has masked the genuine limitations on our knowledge and understanding of our fellow human beings. Some of these rest on ignorance, others on the constitutional indeterminacy of the mental. [ABSTRACT FROM AUTHOR]

Individuals with glucose transporter type I deficiency (G1D) habitually experience nutrient-responsive epilepsy associated with decreased brain glucose. However, the mechanistic association between blood glucose concentration and brain excitability in the context of G1D remains to be elucidated. Electroencephalography (EEG) in G1D individuals revealed nutrition time-dependent seizure oscillations often associated with preserved volition despite electrographic generalization and uniform average oscillation duration and periodicity, suggesting increased facilitation of an underlying neural loop circuit. Nonlinear EEG ictal source localization analysis and simultaneous EEG/functional magnetic resonance imaging converged on the thalamus-sensorimotor cortex as one potential circuit, and 18F-deoxyglucose positron emission tomography (18F-DG-PET) illustrated decreased glucose accumulation in this circuit. This pattern, reflected in a decreased thalamic to striatal 18F signal ratio, can aid with the PET imaging diagnosis of the disorder, whereas the absence of noticeable ictal behavioral changes challenges the postulated requirement for normal thalamocortical activity during consciousness. In G1D mice, 18F-DG-PET and mass spectrometry also revealed decreased brain glucose and glycogen, but preserved tricarboxylic acid cycle intermediates, indicating no overall energy metabolism failure. In brain slices from these animals, synaptic inhibition of cortical pyramidal neurons and thalamic relay neurons was decreased, and neuronal disinhibition was mitigated by metabolic sources of carbon; tonic-clonic seizures were also suppressed by α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor inhibition. These results pose G1D as a thalamocortical synaptic disinhibition disease associated with increased glucose-dependent neuronal excitability, possibly in relation to reduced glycogen. Together with findings in other metabolic defects, inhibitory neuron dysfunction is emerging as a modulable mechanism of hyperexcitability. Fuel-dependent inhibition: Glucose transporter type I deficiency (G1D) is characterized by reduced brain glucose and development of treatment-resistant epilepsy. Here, Rajasekaran et al. use electroencephalography and imaging data from individuals with G1D and showed that the thalamus/sensorimotor cortex circuit might be a critical area involved in the increased brain excitability and the development of seizures. In a mouse model of G1D, the authors showed no energy metabolism impairments, whereas synaptic inhibition of cortical pyramidal and thalamic cells was reduced. Switch in carbon source restored inhibitory activity, and inhibition of AMPA receptor reduced seizures in mice, suggesting that failure of the inhibitory synapses of the circuit might be the main cause of seizure activity in G1D. [ABSTRACT FROM AUTHOR]

It is sometimes argued that Wittgenstein's conception of grammar and the role he allocated to grammar (in his sense of the term) in philosophy changed between the Big Typescript and the Philosophical Investigations. It is also held that some of the grammatical propositions Wittgenstein asserted prior to his writing of the Philosophical Investigations are theses, doctrines, opinions or dogmatism, which he abandoned by 1936/37. The purpose of this paper is to show these claims to be misunderstandings and misinterpretations. On all important matters, his conception of grammar and of grammatical investigations, of grammatical statements or propositions and of grammatical clarification did not change between the Big Typescript and the Investigations. Grammatical propositions (e.g. the meaning of a word is its use; a sample in an ostensive definition belongs to the means of representation; belief is not a mental state) are no more theses, doctrines or opinions than is 'a bachelor is an unmarried man.' Nor are they in any way dogmatic. [ABSTRACT FROM AUTHOR]

The experimental study of the emotions as pursued by LeDoux and Damasio is argued to be flawed as a consequence of the inadequate conceptual framework inherited from the work of William James. This paper clarifies the conceptual structures necessary for any discussion of the emotions. Emotions are distinguished from appetites and other non-emotional feelings, as well as from agitations and moods. Emotional perturbations are distinguished from emotional attitudes and motives. The causes of an emotion are differentiated from the objects of an emotion, and the objects of an emotion are distinguished into formal and material ones. The links between emotions and reasons for the emotion, for associated beliefs and for action are explored, as well as the connection between emotion and care or concern, and between emotion and fantasy. The behavioural criteria for the ascription of an emotion are clarified. In the light of this conceptual network, Damasio's theory of the emotions is subjected to critical scrutiny and found wanting.