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ObjectiveHow responsive neurostimulation (RNS) decreases seizure frequency is unclear. Stimulation may alter epileptic networks during inter-ictal epochs. Since fast ripples (FR) may be a substrate of the epileptic network, we examined whether stimulation of FR generating networks differed in RNS super- and intermediate-responders.MethodsIn 10 patients, we detected FR during sleep from stereo EEG (SEEG) contacts during the pre-surgical evaluation in patients with subsequent RNS placement. The normalized coordinates of the SEEG contacts were compared with that of the eight RNS contacts, and RNS stimulated SEEG contacts were defined as within 1.5 cm3of the RNS contacts. We compared the post-RNS placement seizure outcome to 1) the ratio of stimulated SEEG contacts in the seizure-onset zone (SOZ SR); 2) the ratio of FR events on stimulated contacts (FR SR); and 3) the global efficiency of the FR temporal correlational network on stimulated contacts (FR SGe).ResultsWe found that the SOZ SR (p=0.18) and FR SR (p=0.06) did not differ in the RNS super- and intermediate-responders, but the FR SGe did (p=0.02). In super-responders highly active desynchronous sites of the FR network were stimulated.SignificanceRNS that better targets FR networks, as compared to the SOZ, may reduce epileptogenicity more.Short summaryResponsive neurostimulation (RNS) may reduce seizures by altering the epileptic network. Fast ripples (FR) may be a substrate of the epileptic network. We investigated, in 10 patients, if RNS stimulation of FR generating brain differed in RNS super-responders and intermediate-responders. The RNS stimulated brain sites were defined as contacts in the pre-surgical stereo EEG implant within 1.5 cm3of the subsequently placed RNS stimulation contacts. FR events were more highly active and temporally desynchronous (p

This roundtable discussion is based on an online symposium – The Promise of Photography: Scale, Measure and Proportion in a Conflicted Visual Milieu – which took place on 17 September 2021. Since its inception, photography has promised to set things to scale, to grant them measure and proportion, a series of promises that have also entailed moments of irrationality or conflict that persist in and continue to shape the era of global networked digital imaging technologies. The symposium started out from the diagnosis that, whilst photography continues to promise an ordered, proportionate and measured world in which things can be set to their proper scale, it also acts in many ways as an agent of dismeasure, disproportion and the unscalable. In light of this, the roundtable discussion presented here examines a range of different meanings that scale, measure and proportion have accrued in the photographic context and sets out to explore conceptual frameworks and research methodologies through which the current situation might be understood.

Fast ripples (FR) are a biomarker of epileptogenic brain, but when larger portions of FR generating regions are resected seizure freedom is not always achieved. To evaluate and improve the diagnostic accuracy of FR resection for predicting seizure freedom we compared the FR resection ratio (RR) with FR network graph theoretical measures. In 23 patients FR were semi-automatically detected and quantified in stereo EEG recordings during sleep. MRI normalization and co-registration localized contacts and relation to resection margins. The number of FR, and graph theoretical measures, which were spatial (i.e., FR rate-distance radius) or temporal correlational (i.e., FR mutual information), were compared with the resection margins and with seizure outcome We found that the FR RR did not correlate with seizure-outcome (p > 0.05). In contrast, the FR rate-distance radius resected difference and the FR MI mean characteristic path length RR did correlate with seizure-outcome (p

Fast ripples (FR) are a biomarker of epileptogenic brain, but when larger portions of FR generating regions are resected seizure freedom is not always achieved. To evaluate and improve the diagnostic accuracy of FR resection for predicting seizure freedom we compared the FR resection ratio (RR) with FR network graph theoretical measures. In 23 patients FR were semi-automatically detected and quantified in stereo EEG recordings during sleep. MRI normalization and co-registration localized contacts and relation to resection margins. The number of FR, and graph theoretical measures, which were spatial (i.e., FR rate-distance radius) or temporal correlational (i.e., FR mutual information), were compared with the resection margins and with seizure outcome We found that the FR RR did not correlate with seizure-outcome (p > 0.05). In contrast, the FR rate-distance radius resected difference and the FR MI mean characteristic path length RR did correlate with seizure-outcome (p

‘It is at work everywhere, functioning smoothly at times, at other times in fits and starts. It breathes, it heats, it eats. It shits and fucks. What a mistake to have said the id. Everywhere it is...

The medial temporal lobe (MTL) encodes and recalls memories and can be a predominant site for interictal spikes (IS) in patients with focal epilepsy. It is unclear whether memory deficits are due to IS in the MTL producing a transient decline. Here, we investigated whether IS in the MTL subregions and lateral temporal cortex impact episodic memory encoding and recall.Seventy-eight participants undergoing presurgical evaluation for medically refractory focal epilepsy with depth electrodes placed in the temporal lobe participated in a verbal free recall task. IS were manually annotated during the pre-encoding, encoding, and recall epochs. We examined the effect of IS on word recall using mixed-effects logistic regression.IS in the left hippocampus (odds ratio [OR] = .73, 95% confidence interval [CI] = .63-.84, p .001) and left middle temporal gyrus (OR = .46, 95% CI = .27-.78, p .05) during word encoding decreased subsequent recall performance. Within the left hippocampus, this effect was specific for area CA1 (OR = .76, 95% CI = .66-.88, p .01) and dentate gyrus (OR = .74, 95% CI = .62-.89, p .05). IS in other MTL subregions or inferior and superior temporal gyrus and IS occurring during the prestimulus window did not affect word encoding (p .05). IS during retrieval in right hippocampal (OR = .22, 95% CI = .08-.63, p = .01) and parahippocampal regions (OR = .24, 95% CI = .07-.8, p .05) reduced the probability of recalling a word.IS in medial and lateral temporal cortex contribute to transient memory decline during verbal episodic memory.

This article suggests that when the engagement with photography is limited to questions of recognition and resemblance, such approach stifles our experience of the world and directs us towards monotonous homogeneity in which everything can be represented in a photograph, and a photograph is always a representation of something or other. And yet, a photograph has the potential to move our gaze beyond representation of events and situations in a way that allows us to penetrate the appearance of things and to sense their inner reality, rather than act as a mere illustration.

The epileptic network hypothesis and epileptogenic zone hypothesis are two theories of ictogenesis. The network hypothesis posits that coordinated activity among interconnected nodes produces seizures. The epileptogenic zone hypothesis posits that distinct regions are necessary and sufficient for seizure generation. High-frequency oscillations, and particularly fast ripples, are thought to be biomarkers of the epileptogenic zone. We sought to test these theories by comparing high-frequency oscillation rates and networks in surgical responders and non-responders, with no appreciable change in seizure frequency or severity, within a retrospective cohort of 48 patients implanted with stereo-EEG electrodes. We recorded inter-ictal activity during non-rapid eye movement sleep and semi-automatically detected and quantified high-frequency oscillations. Each electrode contact was localized in normalized coordinates. We found that the accuracy of seizure onset zone electrode contact classification using high-frequency oscillation rates was not significantly different in surgical responders and non-responders, suggesting that in non-responders the epileptogenic zone partially encompassed the seizure onset zone(s) (P > 0.05). We also found that in the responders, fast ripple on oscillations exhibited a higher spectral content in the seizure onset zone compared with the non-seizure onset zone (P 350 Hz. The first was a rate–distance network that multiplied the Euclidian distance between fast ripple-generating contacts by the average rate of fast ripple in the two contacts. The radius of the rate–distance network, which excluded seizure onset zone nodes, discriminated non-responders, including patients not offered resection or responsive neurostimulation due to diffuse multifocal onsets, with an accuracy of 0.77 [95% confidence interval (CI) 0.56–0.98]. The second fast ripple network was constructed using the mutual information between the timing of the events to measure functional connectivity. For most non-responders, this network had a longer characteristic path length, lower mean local efficiency in the non-seizure onset zone, and a higher nodal strength among non-seizure onset zone nodes relative to seizure onset zone nodes. The graphical theoretical measures from the rate–distance and mutual information networks of 22 non- responsive neurostimulation treated patients was used to train a support vector machine, which when tested on 13 distinct patients classified non-responders with an accuracy of 0.92 (95% CI 0.75–1). These results indicate patients who do not respond to surgery or those not selected for resection or responsive neurostimulation can be explained by the epileptic network hypothesis that is a decentralized network consisting of widely distributed, hyperexcitable fast ripple-generating nodes.

Purpose The clinical significance of postoperative pseudomeningocele formation following optic nerve sheath fenestration (ONSF) has not been fully characterized. A literature review identifies 9 previously published cases the authors believe demonstrate pseudomeningocele formation and approximately 19 other similar findings that were either transient or less defined blebs. This study was undertaken to more clearly define the clinical, radiographic, and histopathologic features associated with this entity. Methods Sixteen-year, single-center, retrospective chart review of all ONSF cases performed by 2 surgeons. Clinical data, intracranial pressure, radiographic imaging, and histopathology of clinically detected pseudomeningoceles after ONSF were reviewed. Results Eighty-six eyes in 57 patients underwent ONSF (28 unilateral, 12 bilateral sequential, 17 bilateral simultaneous). Forty-nine of 57 patients had elevated intracranial pressure preoperatively (41 idiopathic intracranial hypertension, 4 venous thrombosis, 2 meningitis, 1 arteriovenous malformation, and 1 sarcoid). In 32 patients undergoing postoperative imaging, 4 eyes (4.7%) in 4 patients developed well-defined pseudomeningoceles, of which 3 were symptomatic and 2 required surgical revision. Each pseudomeningocele developed in the setting of elevated preoperative intracranial pressure (350, 360, 430, 500 mm H20). Magnetic resonance imaging and/or computed tomography revealed sharply demarcated fluid-filled sacs adjacent to the optic nerve. The contents of these sacs were hypointense on T1-weighted imaging, hyperintense on T2-weighting, variably enhanced with contrast, and hypointense on fluid attenuated inversion recovery, and were thus consistent with cerebrospinal fluid. Histopathologic analysis of one of these outpouchings demonstrated an acellular, fibrocollagenized lining consistent with pseudomeningocele. Three eyes in 3 additional patients had less well-defined findings on imaging interpreted as bleb-like or cyst-like change. Conclusions Pseudomeningoceles following ONSF may be asymptomatic or may cause symptomatic orbital mass effect and rarely visual loss, amendable to surgical excision. Post-ONSF pseudomeningoceles are identified on computed tomography or magnetic resonance imaging to occur at the locations of fenestration sites and contain cerebrospinal fluid communicating with the subdural space that may act as a "filtration" bleb in some cases. Imaging findings may represent a spectrum spanning intraorbital cerebrospinal fluid leakage, partial walling off of bleb, or fully developed cysts. Resection of optic nerve pseudomeningoceles is considered in symptomatic cysts or eyes with papilledema that fails to improve.

From Kant to postmodernism the idea of the sublime was always tied with questions of ethics and politics. Kant saw the sublime as a proof that rationality triumphs over nature, validating law and judgement through the subjective experience of pleasure and pain. Lyotard saw in the sublime a symptom of a crisis at which rationality reaches its limit, and subjectivity is confronted with its own collapse. As this chapter will show, both these approaches are inadequate to account for the sublime in 21st century. The failure of liberal democracy and the rise of populist and fascist ideologies calls for a re-evaluation of the sublime as the dissolution of the symbolic order and the coming face to face with the alternative reality of the death drive. This chapter names this reality ‘The Diogenes Complex’, after the homeless beggar who made his form of existence the manifestation of his philosophical creed. Through his performative actions Diogenes has shown that reality is sublime because it is irreconcilable with rational logic and warned against the futility of trying to act rationally in irrational times.

Intravascular papillary endothelial hyperplasia (IPEH) is a benign vascular lesion, typically found in the skin, consisting of a papillary proliferation of endothelial cells intimately related to a thrombus; it appears to be a rare variant of an organizing process. IPEH very rarely develops in the periocular region, with fewer than 20 such cases currently reported in the English language literature. We describe one of the largest ever case series of this uncommon lesion occurring in the periocular region and discuss its clinical features, imaging characteristics, and surgical management.

In the twentieth-century photography was the de-facto face of representation, as the visual arm of an industrial society that thought to reproduce the world as commodity for the consumption by individuals. However, in the twenty-first century this logic of mechanical reproduction is augmented by the (fuzzy) logic of algorithmic processing, which does not require individuals and commodities for its operation, but converts both to packets of data. The task of photography today is not to represent the world as an image, but to explore the conditions that make something like an ‘image’ possible.

Critical approaches to photography have one thing in common: they share an understanding that photographs must be approached visually. They take it as a given that photographs are pictures to be looked at, and they all agree that it is only through looking that photographs communicate. Whatever subsequent interpretations follow, the priority of vision in relation to the image remains unperturbed. This belief in the visibility of the photograph imperceptibly bonded together otherwise dissimilar and sometimes contradictory methodologies, preventing them from noticing that which is the most unexplained about photography: the precedence of looking itself. This self-evident truth of visibility blocks the possibility of inquiring after everything that is non-visual in a picture. However, the digital image forces a reevaluation of visibility because it clear that the visible cannot account for images that begin their life as binary data, developed algorithmically and driven to various points across the network not as individual pictures but as packets of data. Through a reading of Heidegger, Deleuze and Benjamin this paper suggests that digital-born photography cannot be explained away in representational terms; rather it calls for a theory that can account for proliferation and self-replication as the purveyors of meaning online.

This paper considers the significance of metadata in relation to the image economy of the web. Social practices such as keywording, tagging, rating and viewing increasingly influence the modes of navigation and hence the utility of images in online environments. To a user faced with an avalanche of images, metadata promises to make photographs machine-readable in order to mobilize new knowledge, in a continuation of the archival paradigm. At the same time, metadata enables new topologies of the image, new temporalities and multiplicities which present a challenge to historical models of representation. As photography becomes an encoded discourse, we suggest that the turning away from the visual towards the mathematical and the algorithmic establishes undecidability as a key property of the networked image.

We have previously shown that mouse atherosclerosis regression involves monocyte-derived (CD68+) cell emigration from plaques and is dependent on the chemokine receptor CCR7. Concurrent with regression, mRNA levels of the gene encoding LXRalpha are increased in plaque CD68+ cells, suggestive of a functional relationship between LXR and CCR7. To extend these results, atherosclerotic Apoe-/- mice sufficient or deficient in CCR7 were treated with an LXR agonist, resulting in a CCR7-dependent decrease in plaque CD68+ cells. To test the requirement for LXR for CCR7-dependent regression, we transplanted aortic arches from atherosclerotic Apoe-/- mice, or from Apoe-/- mice with BM deficiency of LXRalpha or LXRbeta, into WT recipients. Plaques from both LXRalpha and LXRbeta-deficient Apoe-/- mice exhibited impaired regression. In addition, the CD68+ cells displayed reduced emigration and CCR7 expression. Using an immature DC line, we found that LXR agonist treatment increased Ccr7 mRNA levels. This increase was blunted when LXRalpha and LXRbeta levels were reduced by siRNAs. Moreover, LXR agonist treatment of primary human immature DCs resulted in functionally significant upregulation of CCR7. We conclude that LXR is required for maximal effects on plaque CD68+ cell expression of CCR7 and monocyte-derived cell egress during atherosclerosis regression in mice.

In light of the triumph of the digital photograph as the basic semantic unit of New Media, this paper investigates the response of photographic education to the culture of ubiquitous mobile and networked photography. It argues that photographic education fails to address such contemporary conditions as the crisis of the visual, the demise of the still photograph and the redundancy of the notion of authorship because it perceives the digital turn in technological terms. This paper suggests that if the digital moment in photography will be approached conceptually rather than technologically, it will present photography educators with a unique opportunity to place the study of the digital photograph at the centre of a culture which is based on reproduction, multiplication and copying.

Twenty‐two years since the arrival of the first consumer digital camera, Western culture is now characterized by ubiquitous photography. The disappearance of the camera inside the mobile phone has ensured that even the most banal moments of the day can become a point of photographic reverie, potentially shared instantly. Supported by the increased affordability of computers, digital storage and access to broadband, consumers are provided with new opportunities for the capture and transmission of images, particularly online where snapshot photography is being transformed from an individual to a communal activity. As the digital image proliferates online and becomes increasingly delivered via networks, numerous practices emerge surrounding the image's transmission, encoding, ordering and reception. Informing these practices is a growing cultural shift towards a conception of the Internet as a platform for sharing and collaboration, supported by a mosaic of technologies termed Web 2.0. In this article we att...

This chapter explores the transformation of the photographic image through differing conceptual and theoretical lenses including that of the algorithm, ‘technē’, continental philosophy and computer science. It contributes to debates in digital aesthetics, networked cultures and non-representational theory. Its innovation is in suggesting that the paradigm of representation, which was established during the European Renaissance, and through which a visual topography of the real world was kept in place, is now challenged by an image producing system based upon computation. The chapter was commissioned by Professor Martin Lister as part of the new edition of ‘The Photographic Image in Digital Culture’ (Routledge, 2013). Research for the work was partially supported by an AHRC network grant; some of the findings were also presented at an international conference, Photo-Media, Helsinki (2012).