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We propose that perceptual quality can be explained by the way neural states figure in dynamic sensorimotor patterns [1xNeural plasticity and consciousness. Hurley, S.L. and Noe, A. Biol. Philos. 2003; 18: 131–168Crossref | Scopus (113)See all References, 2xThe deferential brain in action: Response to Jeffrey Gray. Noe, A. and Hurley, S.L. Trends Cogn. Sci. 2003; 7: 195–196Abstract | Full Text | Full Text PDF | PubMed | Scopus (9)See all References, 3xA sensorimotor approach to vision and visual consciousness. O'Regan, J.K. and Noe, A. Behav. Brain Sci. 2001; 24: 883–975CrossrefSee all References, 4xHurley, S.L. See all References]. Is this a version of functionalism, as Block [5xHow are qualia coupled to function?. Gray, J. Trends Cogn. Sci. 2003; 7: 192–194Abstract | Full Text | Full Text PDF | PubMed | Scopus (19)See all References[5] and Gray [6xTactile sensations/spatial perception. Block, N. Trends Cogn. Sci. 2003; 7: 285–286Abstract | Full Text | Full Text PDF | PubMed | Scopus (18)See all References[6] suggest? No. First, our proposal is compatible with physicalism, that is, with the idea that phenomenology goes with brain state. We reject only a physicalism that holds that properties of cortical states activated by sensory input alone are sufficient for experience. In our view, the relevant neural substrates are dynamic and sensorimotor. Second, we do not hypothesize that function is (or determines) phenomenology. Rather, we propose that sensorimotor context explains the phenomenology. Even on the assumption that phenomenology correlates with neural states, it remains open whether one can bridge the explanatory gaps. One can bridge these gaps, we argue, by looking to dynamic sensorimotor context.Our central claim is empirical: it is possible to explain and predict variations in phenomenology by reference to sensorimotor patterns. For example, applying TMS to V1 during Braille reading by early blind but not normal subjects produces tactile distortions; V1 gives rise to tactile experience because its activation mediates relevant patterns of sensorimotor contingency (e.g. patterns of change in stimulation of the fingers as they move). This point is untouched by Block's observations: (1) that somatosensory cortex is also active during Braille reading; and (2) that V1 may be active in other tactile tasks. Block concludes (3) that it is misleading to speak of visual or tactile cortex, because cortical areas are multi-sensory, and he challenges us (4) to explain the basis of our claim that the phenomenology of Braille is exclusively tactile and not spatial or visual.As for (3), we agree that perceptual areas of the brain are multi-sensory. Activity in V1 is not intrinsically unimodal. Indeed, this is precisely our point: the phenomenology is determined by dynamic patterns of sensorimotor activity. As for (4), we need to be careful: First, there is reason to believe that Braille reading – using fingers to perceive letters and words – is tactile; the burden of proof is on one who claims that Braille readers do not have tactile phenomenology. (Block cannot appeal to the fact that V1 is active during Braille reading, precisely because of the multi-sensory character of neural activity in V1.) Second, a sensory modality isn't spatial as opposed to tactile or visual. Touch and vision are both modalities of spatial perception. But there are differences between the spatial content of touch and that of vision; vision but not touch presents spatial arrays at a distance. Crucially, the spatial content of Braille is that of touch, not vision.This last point is relevant to Block's comments about our treatment of tactile–visual substitution systems (TVSS). We do not claim that the phenomenology of TVSS is exclusively visual, as Block suggests. We insist only that it is not exclusively tactile, and that its spatial content is visual, not tactile. The significance of Block's observation that subjects can concentrate on tactile sensations during TVSS is unclear. Perhaps attention can change the qualities experienced. In any event, the presence of tactile sensations does not make TVSS tactile, for the relevant experiences are not of those sensations.What about the possibility of activity in V1 during TVSS? This would not be evidence against our claim that somatosensory cortex subserves non-tactile phenomenology, just as the existence of activity in somatosensory cortex during Braille reading does not invalidate the claim that V1 subserves touch. This suggests a new, parallel experiment: would TMS to somatosensory cortex in TVSS produce changes in the ‘quasi-visual’ phenomenology of TVSS users? We predict that it would.

This paper describes the development and evaluation of Open University course P653, Caring for Children and Young People, produced by the Centre for Continuing Education in collaboration with the C...

Let R R be a commutative ring, S S an R R -algebra, H H a Hopf R R algebra, both finitely generated and projective as R R -modules, and suppose S S is an H H -object, so that H ∗ = Hom R ( H , R ) {H^{\ast }} = {\operatorname {Hom} _R}(H,R) acts on S S via a measuring. Let I I be the space of left integrals of H ∗ {H^{\ast }} . We say S S has normal basis if S ≅ H S \cong H as H ∗ {H^{\ast }} modules, and S S has local normal bases if S p ≅ H p {S_p} \cong {H_p} as H p ∗ H_p^{\ast } -modules for all prime ideals p p of R R . When R R is a perfect field, H H is commutative and cocommutative, and certain obvious necessary conditions on S S hold, then S S has normal basis if and only if I S = R = S H ∗ IS = R = {S^{{H^{\ast }}}} . If R R is a domain with quotient field K K , H H is cocommutative, and L = S ⊗ R K L = S \otimes {}_RK has normal basis as ( H ∗ ⊗ K ) ({H^{\ast }} \otimes K) -module, then S S has local normal bases if and only if I S = R = S H ∗ IS = R = {S^{{H^{\ast }}}} .

Suppose R is a commutative ring and H a commutative/cocommutative Hopf algebra which is a free R module of prime rank. The set of isomorphism classes of R algebras which are Galois H objects forms an abelian group (see Chase and Sweedler [a]). In this paper we show that when H is an algebra over a special subring of the p-adic integers containing a full set of (p 1)st roots of unity, then the subring consisting of those Galois objects which are isomorphic to H as H* module (H* = Hom,(H, R)) is isomorphic to UE~(R)/[U~(R)]~, where the notation U,(R) means units of R congruent to 1 modx and 5 is a (p 1)st root of an element b of R which will be seen to characterize the Hopf algebra H. The paper is organised as follows. We briefly review notation related to Hopf algebras, integrals, and Galois objects in Section 0. In Section 1 we present the description of Hopf algebras of order p given by Tate and Oort in their paper “Group Schemes of Prime Order” [S]. Such a Hopf algebra H is associated with a pair of constants a, b. In fact Hz R[x]/

Background There is accumulating evidence that circadian disruption, mediated by alterations in melatonin levels, may play an etiologic role in a wide variety of diseases. The degree to which light-at-night (LAN) and other factors can alter melatonin levels is not well-documented. Our primary objective was to evaluate the degree to which estimates of outdoor environmental LAN predict 6-sulftoxymelatonin (aMT6s), the primary urinary metabolite of melatonin. We also evaluated other potential behavioral, sociodemographic, and anthropomorphic predictors of aMT6s. Methods Study participants consisted of 303 members of the California Teachers Study who provided a 24-hour urine specimen and completed a self-administered questionnaire in 2000. Urinary aMT6s was measured using the Bühlmann ELISA. Outdoor LAN levels were estimated from satellite imagery data obtained from the U.S. Defense Meteorological Satellite Program’s (DMSP) Operational Linescan System and assigned to study participants’ geocoded residential address. Information on other potential predictors of aMT6s was derived from self-administered surveys. Neighborhood socioeconomic status (SES) was based on U.S. Census block group data. Results Lower aMT6s levels were significantly associated with older age, shorter nights, and residential locations in lower SES neighborhoods. Outdoor sources of LAN estimated using low-dynamic range DMSP data had insufficient variability across urban neighborhoods to evaluate. While high-dynamic range DMSP offered much better variability, it was not significantly associated with urinary aMT6s. Conclusions Future health studies should utilize the high-dynamic range DMSP data and should consider other potential sources of circadian disruption associated with living in lower SES neighborhoods.