Blind insight: metacognitive discrimination despite chance task performance

Blindsight and other examples of unconscious knowledge and perception demonstrate dissociations between judgment accuracy and metacognition: Studies reveal that participants’ judgment accuracy can be above chance while their confidence ratings fail to discriminate right from wrong answers. Here, we demonstrated the opposite dissociation: a reliable relationship between confidence and judgment accuracy (demonstrating metacognition) despite judgment accuracy being no better than chance. We evaluated the judgments of 450 participants who completed an AGL task. For each trial, participants decided whether a stimulus conformed to a given set of rules and rated their confidence in that judgment. We identified participants who performed at chance on the discrimination task, utilizing a subset of their responses, and then assessed the accuracy and the confidence-accuracy relationship of their remaining responses. Analyses revealed above-chance metacognition among participants who did not exhibit decision accuracy. This important new phenomenon, which we term blind insight, poses critical challenges to prevailing models of metacognition grounded in signal detection theory

High-Speed, Three-Dimensional Quantification of Ladybug Flapping Wing Kinematics During Takeoff

Ladybug wing and body kinematics during takeoff is explored using high-speed stereoscopic images acquired at a rate of 3000 frames per second. A direct linear transformation algorithm is used to quantify positions of selected locations on the body, forewings (elytra), and hindwings. Design and setup of instrumentation and analysis procedures are explained. Flapping frequency is reported. Significant motion of the forewing and other findings are presented and their applications are discussed

Tailored magnetoelastic sensor geometry for advanced functionality in wireless biliary stent monitoring systems

This paper presents three types of wireless magnetoelastic resonant sensors with specific functionalities for monitoring sludge accumulation within biliary stents. The first design uses a geometry with a repeated cell shape that provides two well-separated resonant mode shapes and associated frequencies to permit spatial localization of mass loading. The second design implements a pattern with specific variation in feature densities to improve sensitivity to mass loading. The third design uses narrow ribbons joined by flexible couplers; this design adopts the advantages in flexibility and expandability of the other designs while maintaining the robust longitudinal mode shapes of a ribbon-shaped sensor. The sensors are batch patterned using photochemical machining from 25 µm thick 2605SA1 Metglas™, an amorphous Fe–Si alloy. Accumulation of biliary sludge is simulated with paraffin or gelatin, and the effects of viscous bile are simulated with a range of silicone fluids. Results from the first design show that the location of mass loads can be resolved within ~5 mm along the length of the sensor. The second design offers twice the sensitivity to mass loads (3000–36 000 ppm mg−1) of other designs. The third design provides a wide range of loading (sensitive to at least 10× the mass of the sensor) and survives compression into a 2 mm diameter tube as would be required for catheter-based delivery.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/85405/1/jmm10_7_075040.pd

Design of a Flapping Wing Mechanism for Force Analysis and Optimization

The design of a robotic flapping wing mechanism is discussed. The design allows for dynamic adjustment of flapping trajectory in fluid with three rotational degrees of freedom, while keeping all motors and encoders out of the fluid (i.e., water or oil) to protect critical equipment from potential failure and increase reliability. Mechanism control is discussed. Preliminary optimization using a Box-Behnkin design approach is used and shows successful parameter optimization. Mechanism limitations are addressed

Hypnotic suggestibility is unaffected by a challenging inhibitory task or mental exhaustion

Executive functioning is paramount to the successful exertion of inhibitory control over automatic impulses and desires. Despite disagreements in determining the exact mechanisms responsible for hypnosis, many theories involve the use of, or alterations in, frontal processing and top-down executive functioning. The present study sought to explore this relationship by examining whether a transient state of reduced inhibitory control influences susceptibility to hypnosis. Specifically, participants completed a color naming task designed to place differing demands on inhibitory control processes before experiencing a hypnotic induction and four suggestions. Bayesian analysis indicated substantial evidence that the prior exertion of inhibitory control processes does not influence subsequent susceptibility to hypnotic suggestion. The study provides evidence that inhibitory impairment, often experienced by those with a range of disorders (such as anxiety and depression), should not affect receptiveness to hypnotic procedures

Exploring a search for long-duration transient gravitational waves associated with magnetar bursts

Soft gamma repeaters and anomalous X-ray pulsars are thought to be magnetars, neutron stars with strong magnetic fields of order $\mathord{\sim} 10^{13}$--$10^{15} \, \mathrm{gauss}$. These objects emit intermittent bursts of hard X-rays and soft gamma rays. Quasiperiodic oscillations in the X-ray tails of giant flares imply the existence of neutron star oscillation modes which could emit gravitational waves powered by the magnetar's magnetic energy reservoir. We describe a method to search for transient gravitational-wave signals associated with magnetar bursts with durations of 10s to 1000s of seconds. The sensitivity of this method is estimated by adding simulated waveforms to data from the sixth science run of Laser Interferometer Gravitational-wave Observatory (LIGO). We find a search sensitivity in terms of the root sum square strain amplitude of $h_{\mathrm{rss}} = 1.3 \times 10^{-21} \, \mathrm{Hz}^{-1/2}$ for a half sine-Gaussian waveform with a central frequency $f_0 = 150 \, \mathrm{Hz}$ and a characteristic time $\tau = 400 \, \mathrm{s}$. This corresponds to a gravitational wave energy of $E_{\mathrm{GW}} = 4.3 \times 10^{46} \, \mathrm{erg}$, the same order of magnitude as the 2004 giant flare which had an estimated electromagnetic energy of $E_{\mathrm{EM}} = \mathord{\sim} 1.7 \times 10^{46} (d/ 8.7 \, \mathrm{kpc})^2 \, \mathrm{erg}$, where $d$ is the distance to SGR 1806-20. We present an extrapolation of these results to Advanced LIGO, estimating a sensitivity to a gravitational wave energy of $E_{\mathrm{GW}} = 3.2 \times 10^{43} \, \mathrm{erg}$ for a magnetar at a distance of $1.6 \, \mathrm{kpc}$. These results suggest this search method can probe significantly below the energy budgets for magnetar burst emission mechanisms such as crust cracking and hydrodynamic deformation

Susceptibility to unconscious influences is unaffected by a challenging inhibitory task or mental exhaustion

Unconscious influences have been demonstrated in a variety of behavioural contexts, however, a key question remains – to what extent do such influences vary with our changing mental states? We examine whether a prior inhibitory challenge increases susceptibility to subliminal priming in a stem completion task employing neutral (Experiment 1) and reward salient terms (Experiment 2). Results show stem completions to be significantly influenced by unconscious priming, and the challenging inhibitory task (the Stroop) to be significantly more mentally exhausting than the control task. However, neither the degree of inhibitory challenge, trait self-control, nor task-related mental exhaustion significantly influenced unconscious priming. Bayesian analysis provides strong evidence that prior inhibitory challenge does not affect susceptibility to unconscious priming. The study supports the conclusion that unconscious processing can be independent of consciously experienced mental states and provides reassurance that inhibitory impairment, common to mood disorders, should not increase susceptibility to unconscious influences