Developing a methodology for manipulating spontaneous blinks.

While blinking is necessary for ocular protection and lubrication, people blink much more than is necessary for routine ocular maintenance. These extra, spontaneous blinks are extremely difficult to manipulate and thus, have remained somewhat of a mystery. In order to determine the effects of spontaneous blinks, a methodology to manipulate them naturally must be created. The aim of this study was to develop such methodology using videos of animated speakers displaying high and low blink rates, and determine whether this influenced participant blink rates. It was expected that watching videos of a speaker's face would manipulate blink rate. It was also expected that participants would imitate the speaker's blink timing and blink immediately after the speaker blinks, called blink entrainment. Participants watched four videos, two featuring an animated speaker with a high blink rate, and two featuring the same animated speaker with a low blink rate. In between the speaker videos, participants completed ten trials of several variations of a lexical decision task. The speaker videos provided instructions on how to complete each of these tasks. A Wilcoxon signed-rank test showed that the differences between participant blink rates across the high blink rate and the low blink rate were significant (Z = -3.16, p = .002). Participants blinked more frequently while watching the high blink rate videos than when watching the low blink rate videos. A Wilcoxon signed-rank test also showed a significant difference between entrainment blinks and non-entrainment blinks in the high blink rate condition (Z = -3.65, p = .001), and the low blink rate condition (Z = -2.21, p = .027). These results indicate that a standardized methodology for manipulating spontaneous blinks is possible. With the use of the animated speaker videos, spontaneous blinks can be manipulated

Accident Prevention System and Security for Vehicles

Abstract --This Project focuses mainly on road accidents occurring due to poor indication of sign boards, drowsy state and drunken state of drivers in both two wheelers and four wheelers. The eye blink sensor detects the drowsy state and alarms the driver using buzzer .The alcohol sensor detects the alcohol from breath and stops the engine by micro controller immediately .The light sensor detects the intensity of the light and adjusts it accordingly. The zones are indicated by placing the transmitter modules at particular zones. Vehicle Theft is prevented by making use of Transmitter-Receiver module

Machine Analysis of Facial Expressions

No abstract

Macaques preferentially attend to visual patterns with higher fractal dimension contours.

Animals' sensory systems evolved to efficiently process information from their environmental niches. Niches often include irregular shapes and rough textures (e.g., jagged terrain, canopy outlines) that must be navigated to find food, escape predators, and master other fitness-related challenges. For most primates, vision is the dominant sensory modality and thus, primates have evolved systems for processing complicated visual stimuli. One way to quantify information present in visual stimuli in natural scenes is evaluating their fractal dimension. We hypothesized that sensitivity to complicated geometric forms, indexed by fractal dimension, is an evolutionarily conserved capacity, and tested this capacity in rhesus macaques (Macaca mulatta). Monkeys viewed paired black and white images of simulated self-similar contours that systematically varied in fractal dimension while their attention to the stimuli was measured using noninvasive infrared eye tracking. They fixated more frequently on, dwelled for longer durations on, and had attentional biases towards images that contain boundary contours with higher fractal dimensions. This indicates that, like humans, they discriminate between visual stimuli on the basis of fractal dimension and may prefer viewing informationally rich visual stimuli. Our findings suggest that sensitivity to fractal dimension may be a wider ability of the vertebrate vision system

Eye Blink Detection

Abstract. Nowadays, people spend more time in front of electronic screens like computers, laptops, TV screens, mobile phones or tablets which cause eye blink frequency to decrease. Each blink spreads the tears on the eye cornea to moisture and disinfect the eye. Reduced blink rate causes eye redness and dryness also known as Dry Eye, which belongs to the major symptoms of the Computer Vision Syndrome. The goal of this work is to design eye blink detector which can be used in dry eye prevention system. We have analyzed available techniques for blink detection and designed our own solutions based on histogram backprojection and optical flow methods. We have tested our algorithms on different datasets under various lighting conditions. Inner movement detection method based on optical flow performs better than the histogram based ones. We achieve higher recognition rate and much lower false positive rate than the-state-of-the-art technique presented by Divjak and Bischof

Spontaneous Facial Mimicry Is Enhanced by the Goal of Inferring Emotional States: Evidence for Moderation of Automatic Mimicry by Higher Cognitive Processes

A number of studies have shown that individuals often spontaneously mimic the facial expressions of others, a tendency known as facial mimicry. This tendency has generally been considered a reflex-like automatic response, but several recent studies have shown that the degree of mimicry may be moderated by contextual information. However, the cognitive and motivational factors underlying the contextual moderation of facial mimicry require further empirical investigation. In this study, we present evidence that the degree to which participants spontaneously mimic a target\u27s facial expressions depends on whether participants are motivated to infer the target\u27s emotional state. In the first study we show that facial mimicry, assessed by facial electromyography, occurs more frequently when participants are specifically instructed to infer a target\u27s emotional state than when given no instruction. In the second study, we replicate this effect using the Facial Action Coding System to show that participants are more likely to mimic facial expressions of emotion when they are asked to infer the target\u27s emotional state, rather than make inferences about a physical trait unrelated to emotion. These results provide convergent evidence that the explicit goal of understanding a target\u27s emotional state affects the degree of facial mimicry shown by the perceiver, suggesting moderation of reflex-like motor activities by higher cognitive processes

Magnetoenkefalografialla mitatut hermostolliset vasteet normaalilla ja hitaalla nopeudella esitettyihin silmänräpäyksiin

Objectives. The main function of eye blinking is to moisten and protect the cornea. Therefore it may be surprising that blink rate can convey information about the person's emotional and cognitive state, and that people with abnormal blink rates can be perceived as unfriendly or nervous. Moreover, listeners' blinks have been shown to synchronize with a videotaped speaker's blinks. For these reasons, blinks are suggested to have social functions, as well. The objective of this thesis was to probe the neural correlates of blink viewing with magnetoencephalography (MEG). The research questions were: 1) Do viewed eye blinks elicit observable MEG responses? If they do, which brain regions are involved? 2) How does the response change when the blink video is slowed down? 3) Are the self-produced blinks synchronized with the viewed blinks? Methods. The participants (n = 9) were presented with a video of a neutral female face showing no other movement than a single eye blink. The video was played back with normal speed (blink duration 351 ms) and in slow motion (950 ms); a pair of normal and slow videos was repeated 102 times. Between the blink videos, five other facial expressions were shown, and the participants task was to memorize those expressions. A 306-channel neuromagnetometer recorded the brain responses with a sampling rate of 600 Hz. After averaging and filtering the responses, the mean peak latencies, return-to-baseline durations and amplitudes were compared on the channels showing the strongest peaks. The participants blinks were measured with electro-oculogram (EOG), and the proportion of blinks occurring during the viewed blink was compared with the proportions of blinks at other time points. Results and discussion. Both fast and slow viewed blinks elicited prominent MEG responses. The mean peak latencies of the responses to the slow blinks were longer than those to the normal blink (445 ms vs. 317 ms). The responses to the slow blink also returned to the baseline later (921 ms vs. 537 ms). The maximum responses were equal in amplitude between the normal and slow conditions, contrary to our expectations based on earlier results showing that when the viewed stimuli move faster, the responses are stronger. In accordance with earlier EEG results, the cortical sources, modeled as current dipoles, were located mainly in the occipito-temporal cortical regions in the right hemisphere. The subjects also tended to blink more after the blink in the video (peak around 700 ms after the onset of the viewed blink). In conclusion, eye blinks are likely to have social relevance, and this was the first study to demonstrate with MEG how the human brain reacts to viewed blinks.Tavoitteet. Silmiä räpytellään pääasiassa sen vuoksi, että sarveiskalvo pysyisi kosteana. Siksi saattaa tuntua yllättävältä, että räpäysten tiheys voi paljastaa jotakin henkilön kognitiivisesta tai emotionaalisesta tilasta ja että epätavallinen räpytystiheys voi luoda epäystävällisen tai hermostuneen vaikutelman. Kuulijoiden on lisäksi osoitettu räpyttelevän silmiään samaan tahtiin videolla näkyvän puhujan kanssa. Näiden tulosten perusteella on ehdotettu, että silmänräpäyksillä olisi merkitystä sosiaalisen vuorovaikutuksen kannalta. Tämän tutkimuksen tarkoituksena oli tarkastella nähtyihin silmänräpäyksiin syntyviä aivovasteita magnetoenkefalografiaa (MEG) käyttäen. Tutkimuskysymyksinä olivat: 1) Tuleeko nähtyyn räpäykseen erotettavissa oleva MEG-vaste? Ja jos tulee, mitkä alueet aktivoituvat? 2) Miten vaste muuttuu, kun räpäysvideota hidastetaan? 3) Ajoittuvatko katsojan silmänräpäykset systemaattisesti videon räpäyksiin nähden? Menetelmät. Koehenkilöille (n=9) esitettiin videolla naisen kasvot, joilla ei näkynyt muuta liikettä kuin yksittäinen silmänräpäys. Video näytettiin sekä tavallisella nopeudella (jolloin räpäyksen kesto oli 351 ms) että hidastettuna (950 ms). Video toistettiin kummallakin nopeudella 102 kertaa. Näiden toistojen välissä näytettiin myös viisi videota muista kasvonilmeistä, ja koehenkilöiden tehtävänä oli painaa mieleen nuo ilmeet. Aivovasteet mitattiin 306-kanavaisella neuromagnetometrillä 600 Hz:n näytteenottotaajuudella. Signaalia suodatettiin ja keskiarvoistettiin, ja gradiometripareille laskettiin vektorisummat, jotta vasteiden huippujen viiveitä ja voimakkuuksia sekä vasteiden kestoja voitiin vertailla (kultakin koehenkilöltä valittiin vertailuun se kanava, jossa vaste oli voimakkain). Koehenkilöiden silmänräpäykset rekisteröitiin elektro-okulografialla (EOG), ja räpäysten määrää nähdyn räpäyksen aikana verrattiin räpäysten määriin muina ajanhetkinä. Tulokset ja johtopäätökset. Sekä nopea että hidas silmänräpäys tuottivat selkeitä MEG-vasteita. Vasteiden huippujen viiveet olivat pidempiä hitaille räpäyksille (keskiarvo 445 ms) kuin nopeille (317 ms). Vasteet hitaaseen räpäykseen myös pysyivät pidempään kohinarajan yläpuolella (hitaat 921 ms, nopeat 537 ms). Vasteiden huippujen voimakkuuksissa ei ollut eroa nopean ja hitaan videon välillä, mikä on vastoin aiempia tuloksia, jotka ovat näyttäneet vasteiden voimakkuuden kasvavan ärsykkeiden (nähtyjen pisteiden) liikkuessa nopeammin. Lähteet paikannettiin dipolimallinnuksen avulla takaraivo- ja päälaenlohkon välimaastoon aivokuorelle, mikä on sopusoinnussa aiempien EEG-tulosten kanssa. Lisäksi koehenkilöillä oli taipumus räpytellä enemmän juuri räpäyksen näkemisen jälkeen. Yhteenvetona todettakoon, että silmänräpäyksillä on todennäköisesti merkitystä sosiaalisessa kanssakäymisessä, ja tämä oli ensimmäinen tutkimus, jossa näytettiin MEG:llä, miten aivot reagoivat silmänräpäyksen näkemiseen