Seeing slow and seeing fast: Two limits on perception

Video cameras have a single temporal limit set by the frame rate. The human visual system has multiple temporal limits set by its various constituent mechanisms. These limits appear to form two groups. A fast group comprises specialized mechanisms for extracting perceptual qualities such as motion direction, depth, and edges. The second group, with coarse temporal resolution, includes judgments of the pairing of color and motion, the joint identification of arbitrary spatially separated features, the recognition of words, and high-level motion. These temporally coarse percepts may all be mediated by high-level processes. Working at very different timescales, the two groups of mechanisms collaborate to create our unified visual experience

Failures to bind spatially coincident features

N/AAustralian Research Counci

Fair open access: returning control of scholarly journals to their communities

he problem of how we should transition to open access is now urgent. The current situation is one of exorbitant subscription journals and expensive open-access ones, and to address it requires organised action from academics. The Fair Open Access Alliance, set up to facilitate the conversion of existing subscription journals to open access, is an example of such organisation. Alex Holcombe and Mark C. Wilson outline the group’s five Fair Open Access Principles and encourage all librarians, researchers, and administrators to work together to secure agreement to cancel subscriptions and to pool funds to pay for open access infrastructure

Tracking a single fast-moving object exhausts attentional resources

NOTICE: this is the author’s version of a work that was accepted for publication in Cognition. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication.Driving on a busy road, eluding a group of predators, or playing a team sport involves keeping track of multiple moving objects. In typical laboratory tasks, the number of visual targets that humans can track is about four. Three types of theories have been advanced to explain this limit. The fixed-limit theory posits a set number of attentional pointers available to follow objects. Spatial interference theory proposes that when targets are near each other, their attentional spotlights mutually interfere. Resource theory asserts that a limited resource is divided among targets, and performance reflects the amount available per target. Utilising widely separated objects to avoid spatial interference, the present experiments validated the predictions of resource theory. The fastest target speed at which two targets could be tracked was much slower than the fastest speed at which one target could be tracked. This speed limit for tracking two targets was approximately that predicted if at high speeds, only a single target could be tracked. This result cannot be accommodated by the fixed-limit or interference theories. Evidently a fast target, if it moves fast enough, can exhaust attentional resources.Australian Research Counci

Tracking a single fast-moving object exhausts attentional resources

Driving on a busy road, eluding a group of predators, or playing a team sport involves keeping track of multiple moving objects. In typical laboratory tasks, the number of visual targets that humans can track is about four. Three types of theories have been advanced to explain this limit. The fixed-limit theory posits a set number of attentional pointers available to follow objects. Spatial interference theory proposes that when targets are near each other, their attentional spotlights mutually interfere. Resource theory asserts that a limited resource is divided among targets, and performance reflects the amount available per target. Utilising widely separated objects to avoid spatial interference, the present experiments validated the predictions of resource theory. The fastest target speed at which two targets could be tracked was much slower than the fastest speed at which one target could be tracked. This speed limit for tracking two targets was approximately that predicted if at high speeds, only a single target could be tracked. This result cannot be accommodated by the fixed-limit or interference theories. Evidently a fast target, if it moves fast enough, can exhaust attentional resources.Australian Research Counci

Mass Mobilization in the Democratic Republic of Vietnam, 1945–1960

Immediately after its founding by Hồ Chí Minh in September 1945, the Democratic Republic of Vietnam (DRV) faced challenges from rival Vietnamese political organizations and from a France determined to rebuild her empire after the humiliations of WWII. Hồ, with strategic genius, courageous maneuver, and good fortune, was able to delay full-scale war with France for sixteen months in the northern half of the country. This was enough time for his Communist Party, under the cover of its Vietminh front organization, to neutralize domestic rivals and install the rough framework of an independent state. That fledgling state became a weapon of war when the DRV and France finally came to blows in Hanoi during December of 1946, marking the official beginning of the First Indochina War. With few economic resources at their disposal, Hồ and his comrades needed to mobilize an enormous and free contribution in manpower and rice from DRV-controlled regions. Extracting that contribution during the war’s early days was primarily a matter of patriotic exhortation. By the early 1950s, however, the infusion of weapons from the United States, the Soviet Union, and China had turned the Indochina conflict into a “total war.” Hunger, exhaustion, and violence, along with the conflict’s growing political complexity, challenged the DRV leaders’ mobilization efforts, forcing patriotic appeals to be supplemented with coercion and terror. This trend reached its revolutionary climax in late 1952 when Hồ, under strong pressure from Stalin and Mao, agreed to carry out radical land reform in DRV-controlled areas of northern Vietnam. The regime’s 1954 victory over the French at Điện Biên Phủ, the return of peace, and the division of the country into North and South did not slow this process of socialist transformation. Over the next six years (1954–1960), the DRV’s Communist leaders raced through land reform and agricultural collectivization with a relentless sense of urgency. Mass Mobilization in the Democratic Republic of Vietnam, 1945–1960 explores the way the exigencies of war, the dreams of Marxist-Leninist ideology, and the pressures of the Cold War environment combined with pride and patriotism to drive totalitarian state formation in northern Vietnam.Open Access publication of this book was made possible by the Sustainable History Monograph Pilot, an initiative sponsored by the Andrew W. Mellon Foundation

The Effect of Visual Distinctiveness on Multiple Object Tracking Performance

Observers often need to attentively track moving objects. In everyday life, such objects are often visually distinctive. Previous studies have shown that tracking accuracy is increased when the targets contain a visual feature (e.g. a colour) not possessed by the distractors. Conversely, a gain in tracking accuracy was not observed when the targets differed from the distractors by only a conjunction of features (Makovski & Jiang, Visual Cognition, 17(1/2), 180). In this study we confirm that some conjunction targets have relatively little effect on tracking accuracy, but show that other conjunction targets can significantly aid tracking. For example, tracking accuracy is relatively high when the targets are small red squares and half the distractors are large red squares while the remaining distractors are small green squares. This seems to occur because the targets have a set of features (small and red) not shared by any one distractor. Attending to these features directs attention more to the targets than the distractors, thereby making the targets easier to track. Existing theories of attentive tracking cannot explain these results

A critical systematic review of the Neurotracker perceptual-cognitive training tool

In this systematic review, we evaluate the scientific evidence behind“Neurotracker,”one of the most popular perceptual-cognitive training tools in sports. The tool, which is also used in rehabilitation and aging research to examine cognitive abilities,uses a 3D multiple object-tracking (MOT) task. In this review, we examine Neurotracker from both a sport science and a basicscience perspective. We first summarize the sport science debate regarding the value of general cognitive skill training, based ontools such as Neurotracker, versus sport-specific skill training. We then consider the several hundred MOT publications incognitive and vision science from the last 30 years that have investigated cognitive functions and object tracking processes.This literature suggests that the abilities underlying object tracking are not those advertised by the Neurotracker manufacturers.With a systematic literature search, we scrutinize the evidence for whether general cognitive skills can be tested and trained withNeurotracker and whether these trained skills transfer to other domains. The literature has major limitations, for example a totalabsence of preregistered studies, which makes the evidence for improvements for working memory and sustained attention veryweak. For other skills as well, the effects are mixed. Only three studies investigated far transfer to ecologically valid tasks, two ofwhich did not find any effect. We provide recommendations for future Neurotracker research to improve the evidence base andfor making better use of sport and basic science finding

Online Evidence Charts to Help Students Systematically Evaluate Theories and Evidence

To achieve intellectual autonomy, university students should learn how to critically evaluate hypotheses and theories using evidence from the research literature. Typically this occurs in the context of writing an essay, or in planning the introduction and conclusion sections of a laboratory project. To be successful, a student must distill relevant evidence from the research literature, evaluate evidence quality, and evaluate hypotheses or theories in light of the evidence. To help students achieve these goals, we have created a web-based “evidence-charting” tool (available at www.evidencechart.org). The main feature of the website is an interactive chart, providing students a structure to list the evidence (from research articles or experiments), list the theories, and enter their evaluation of how the evidence supports or undermines each theory/hypothesis. The chart also elicits from students their reasoning about why the evidence supports or undermines each hypothesis, and invites them to consider how someone with an opposing view might respond. The online chart provides a summary view of the evidence the student has indicated to be most important, and discussion tools to elaborate on this information. Upon completing a chart, the student is well positioned to write their essay or report, and the instructor has an at-a-glance view to provide formative feedback indicating whether the student has successfully reviewed the literature and understands the evidence and theories. These benefits are being evaluated in the context of introductory and advanced psychology classes