scholarly journals Attention and the motion after effect: New measurements with visual search reveal important individual differences in adaptability

2018 ◽  
Author(s):  
Michael J. Morgan ◽  
Joshua A. Solomon

AbstractIt is usually assumed that sensory adaptation is a universal property of human vision. However, in two experiments designed to measure adaptation without bias, we have discovered a minority of participants who were unusual in the extent of their adaptation to motion. One experiment was designed so that targets would be invisible without adaptation; the other, so that adaptation would interfere with target detection. In the first, participants adapted to a spatial array of moving Gabor patches. On each trial the adapting array was followed by a test array in which but all of the test patches except one were identical to their spatially corresponding adaptors; the target moved in the opposite direction to its adaptor. Participants were required to identify the location of the changed target with a mouse click. The ability to do so increased with the number of adapting trials. Neither search speed nor accuracy was affected by an attentionally-demanding conjunction task at the fixation point during adaptation, suggesting low-level (pre-attentive) sites in the visual pathway for the adaptation. However, a minority of participants found the task virtually impossible. In the second experiment the same participants were required to identify the one element in the test array that was slowly moving: reaction times in this case were elevated following adaptation. The putatively weak adapters from the first experiment found this task easier than the strong adapters.

2019 ◽  
Vol 72 (12) ◽  
pp. 2848-2864 ◽  
Author(s):  
Michael J Morgan ◽  
Joshua A Solomon

We measured the effects of attentional distraction on the time course and asymptote of motion adaptation strength, using visual search performance (percent correct and reaction time). In the first two experiments, participants adapted to a spatial array of moving Gabor patches, either all vertically oriented (Experiment 1) or randomly oriented (Experiment 2). On each trial, the adapting array was followed by a test array in which all of the test patches except one were identical in orientation and movement direction to their retinotopically corresponding adaptors, but the target moved in the opposite direction to its adaptor. Participants were required to identify the location of the changed target with a mouse click. The ability to do so increased with the number of adapting trials. Neither search speed nor accuracy was affected by an attentionally demanding conjunction task at the fixation point during adaptation, suggesting low-level (preattentive) sites in the visual pathway for the adaptation. In Experiment 3, the same participants were required to identify the one element in the test array that was slowly moving. Reaction times in this case were elevated following adaptation, but once again there was no significant effect of the distracting task upon performance. In Experiment 4, participants were required to make eye movements, so that retinotopically corresponding adaptors could be distinguished from spatiotopically corresponding adaptors. Performance in Experiments 1 and 2 correlated positively with reaction times in Experiment 3, suggesting a general trait for adaptation strength.


Imbizo ◽  
2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Naomi Epongse Nkealah ◽  
Olutoba Gboyega Oluwasuji

Ideas of nationalisms as masculine projects dominate literary texts by African male writers. The texts mirror the ways in which gender differentiation sanctions nationalist discourses and in turn how nationalist discourses reinforce gender hierarchies. This article draws on theoretical insights from the work of Anne McClintock and Elleke Boehmer to analyse two plays: Zintgraff and the Battle of Mankon by Bole Butake and Gilbert Doho and Hard Choice by Sunnie Ododo. The article argues that women are represented in these two plays as having an ambiguous relationship to nationalism. On the one hand, women are seen actively changing the face of politics in their societies, but on the other hand, the means by which they do so reduces them to stereotypes of their gender.


Author(s):  
Hugh H. Benson
Keyword(s):  
The One ◽  

This chapter presents a reading of Plato’s Euthyphro, Apology, and Crito. These dialogues, in which Plato depicts the weeks leading up to Socrates’s last day, are replete with various philosophical explorations. Among those explorations is the question of how to live our lives. On the one hand, Socrates is clear and straightforward. We should live the examined life—making logoi and examining ourselves and others in order to determine whether we are as wise as we think we are, and we should live the virtuous life. This is how Socrates lives his life. On the other hand, the examined life undercuts, or at least should undercut, the confidence with which he seeks to live the virtuous life. It may help bring some stability to the general principles by which he lives his life, but it can do so only defeasibly and without certainty.


1998 ◽  
Vol 16 (4) ◽  
pp. 387-400 ◽  
Author(s):  
Felicity J Callard

Geographers are now taking the problematic of corporeality seriously. ‘The body’ is becoming a preoccupation in the geographical literature, and is a central figure around which to base political demands, social analyses, and theoretical investigations. In this paper I describe some of the trajectories through which the body has been installed in academia and claim that this installation has necessitated the uptake of certain theoretical legacies and the disavowal or forgetting of others. In particular, I trace two related developments. First, I point to the sometimes haphazard agglomeration of disparate theoretical interventions that lie under the name of postmodernism and observe how this has led to the foregrounding of bodily tropes of fragmentation, fluidity, and ‘the cyborg‘. Second, I examine the treatment of the body as a conduit which enables political agency to be thought of in terms of transgression and resistance. I stage my argument by looking at how on the one hand Marxist and on the other queer theory have commonly conceived of the body, and propose that the legacies of materialist modes of analysis have much to offer current work focusing on how bodies are shaped by their encapsulation within the sphere of the social. I conclude by examining the presentation of corporeality that appears in the first volume of Marx's Capital. I do so to suggest that geographers working on questions of subjectivity could profit from thinking further about the relation between so-called ‘new’ and ‘fluid’ configurations of bodies, technologies, and subjectivities in the late 20th-century world, and the corporeal configurations of industrial capitalism lying behind and before them.


2021 ◽  
Vol 24 (1) ◽  
pp. 37-46
Author(s):  
João Carlos Coimbra ◽  
Tiago Menezes Freire

A robust biostratigraphic zonation based on microfossils supports the stratigraphic framework and correlation of the interior basins of the Lower Cretaceous of NE Brazil. This zonation has also allowed correlations with coeval sections in the Brazilian marginal basins and in the Gabon and Congo basins (central-west Africa). These records, consisting mainly of non-marine sediments, were a great challenge with regard to the correlation with the International Chronostratigraphic Chart. Therefore, local stages were used, the most recent being the Alagoas local Brazilian Stage, with which the Post-rift Sequence I of the Araripe Basin is related. Regarding lithostratigraphy, this sequence includes the Rio da Batateira (Barbalha for some authors) and Santana formations, the last one with the famous Crato, Ipubi, and Romualdo members, from the base to the top. Although currently there is a consensus on the age of the Alagoas local Brazilian Stage in the Araripe Basin, recently a new age for at least part of the Post-rift Sequence I was proposed. This new proposal, based on isotopic analysis of Re-Os, arose as a panacea to correlate the Rio da Batateira Formation and the Crato and Ipubi members with the international stages. Surprisingly, their authors, although on the one hand, they seem to underestimate biostratigraphic results, on the other they seek to support their proposal from microfossils studied by previous authors, but they do so in an inappropriate way, leading readers to misinterpret their results. Therefore, this paper presents a critical review on the age of the Alagoas local Brazilian Stage in the Araripe Basin and nearby basins, refuting a Barremian age for part of the Post-rift Sequence I. Keywords: Alagoas local Brazilian Stage, biostratigraphy, ostracods, palynomorphs, radiometric ages.


2018 ◽  
Vol 49 ◽  
pp. 1-14
Author(s):  
Franz A. J. Szabo

In his great 1848 historical drama,Ein Bruderzwist im Hause Habsburg, the Austrian playwright Franz Grillparzer has Emperor Matthias utter the words that have often been applied to understanding the whole history of the Habsburg monarchy:Das ist der Fluch von unserm edeln Haus:Auf halben Wegen und zu halber TatMit halben Mitteln zauderhaft zu streben.[That is the curse of our noble house:Striving hesitatingly on half waysto half action with half means.]True as those sentiments may be of many periods in the history of the monarchy, the one period of which it cannotbe said is the second half of eighteenth century. The age of Maria Theresa, Joseph II, and Leopold II was perhaps the greatest era of consistent and committed reform in the four-hundred-year history of the monarchy. What I want to address in this article are some aspects of the dynamic of this reform era, and this falls into two categories. On the one hand, there is the broad energizing or motive force behind the larger development, and on the other, there are the ideas or assumptions that lay behind the policies adopted. As might be evident from the subtitle of my article, I propose to look primarily at the second of these categories. I do so because I think while Habsburg historiography has reached considerable consensus on the first, it has not looked enough on the second as an explanatory hermeneutic.


2020 ◽  
pp. 161-176
Author(s):  
Ian Maclachlan

This chapter focuses on Louis-René des Forêts’s poetic sequence, Poèmes de Samuel Wood (1988) in order to highlight the relationship between poetic form, authorial voice and the genre of autobiography. Des Forêts’s sequence comprises a 559-line poem divided into thirteen sections, attributed by its title to the heteronymous author-figure Samuel Wood. Notwithstanding its form and authorial disguise, the poem is obliquely autobiographical and forms part of the overall project of the long, final phase of his writing, best exemplified by the fragmentary work of 1997, Ostinato. My analysis seeks to stake out a distinctive way of conceiving the relation of poetic form to autobiographical genre (taking a distance, notably, from Lejeunian typological approaches), and in order to do so endeavours, on the one hand, to work with the idea of form as active, dynamic and mobile, a process of forming, deforming and reforming which is always temporally emergent and variable, rather than a structure that might simply contain something like content or experience, and on the other hand, to connect that mobility of form to des Forêts’s pursuit of a distinctive autobiographical mode. Far from reflecting and securing authorial identity, this mode might be considered as one that concerns an impersonal or anonymous level of experience that is fundamentally insecure and ultimately inappropriable; we might think of this mode as a kind of degree zero of autobiography, an autobiography in the neuter, or an ‘autobiographie intérieure’.


2021 ◽  
pp. 201-220
Author(s):  
Andrew Rudalevige

The concluding chapter summarizes the overall findings and pushes them toward related topics in sore need of additional study. It examines what happens before an executive order is issued, but we know little about what happens afterward. The conclusion is also a chance to explore the question of bureaucratic capacity and autonomy as it runs up against presidential desires to control that bureaucracy — a claim bolstered by electoral legitimacy. Presidential hostility to the permanent government is hardly new, of course. But the Trump administration's amplification of that contention — with frequent, personal attacks on agencies and even individual civil servants on the one hand, and “resistance” to presidential preferences on the other — raised its salience, and its stakes. The argument of this book rests in part on the value presidents derive — substantively but also politically — from astute management of a bureaucracy that can provide expert advice on solving pressing national problems. Undermining its ability to do so is therefore counterproductive.


Archaeologia ◽  
1951 ◽  
Vol 94 ◽  
pp. 57-96
Author(s):  
D. J. Cathcart King
Keyword(s):  
The One ◽  

The great medieval citadel of Damascus has not apparently received any serious notice in English; the important monographs, in French and German, which have been devoted to it are concerned principally with general architecture on the one part, and with epigraphy on the other. It is not intended in this article to deal further with these particular topics—indeed, the author is not qualified to do so—but to describe the citadel as a fortress and a monument of Islamic military art.


2019 ◽  
Vol 5 (1) ◽  
pp. 311-331
Author(s):  
Suwei Wu ◽  
Alan Cienki

AbstractAn increasing number of studies are being devoted to the investigation of what aspects of grammar, and of events, expressed in speech are coordinated with gesture. However, previous studies have focused on gesture use in relation to either transitivity or event properties, without considering how these factors interact. In this study, we consider how gesture use relates to transitivity when the type of event in the causativeinchoative alternation is considered, and also how gesture use relates to properties of the events when the type of transitivity is considered. We found various relations both between gesture use and transitivity on the one hand, and between gesture use and certain properties of events on the other hand. Whereas some of the results contrast with the findings in previous studies about the relation between gesture and transitivity, other results obtained actually reinforce and complement some previous findings. The results concerning event properties and gesture also add to previous studies about which properties of certain motor-spatial events relate to gesture and how they do so. The study thus provides a more nuanced understanding of the relation between gesture and language.


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