Criminal investigations often use photographic evidence to identify suspects. Here we combined robust face perception and high-resolution photography to mine face photographs for hidden information. By zooming in on high-resolution face photographs, we were able to recover images of unseen bystanders from reflections in the subjects' eyes. To establish whether these bystanders could be identified from the reflection images, we presented them as stimuli in a face matching task (Experiment 1). Accuracy in the face matching task was well above chance (50%), despite the unpromising source of the stimuli. Participants who were unfamiliar with the bystanders' faces (n = 16) performed at 71% accuracy [t(15) = 7.64, p<.0001, d = 1.91], and participants who were familiar with the faces (n = 16) performed at 84% accuracy [t(15) = 11.15, p<.0001, d = 2.79]. In a test of spontaneous recognition (Experiment 2), observers could reliably name a familiar face from an eye reflection image. For crimes in which the victims are photographed (e.g., hostage taking, child sex abuse), reflections in the eyes of the photographic subject could help to identify perpetrators.
- Proceedings of the National Academy of Sciences of the United States of America
- Published over 1 year ago
The power of visual imagery is well known, enshrined in such familiar sayings as “seeing is believing” and “a picture is worth a thousand words.” Iconic photos stir our emotions and transform our perspectives about life and the world in which we live. On September 2, 2015, photographs of a young Syrian child, Aylan Kurdi, lying face-down on a Turkish beach, filled the front pages of newspapers worldwide. These images brought much-needed attention to the Syrian war that had resulted in hundreds of thousands of deaths and created millions of refugees. Here we present behavioral data demonstrating that, in this case, an iconic photo of a single child had more impact than statistical reports of hundreds of thousands of deaths. People who had been unmoved by the relentlessly rising death toll in Syria suddenly appeared to care much more after having seen Aylan’s photograph; however, this newly created empathy waned rather quickly. We briefly examine the psychological processes underlying these findings, discuss some of their policy implications, and reflect on the lessons they provide about the challenges to effective intervention in the face of mass threats to human well-being.
Two studies examined whether photographing objects impacts what is remembered about them. Participants were led on a guided tour of an art museum and were directed to observe some objects and to photograph others. Results showed a photo-taking-impairment effect: If participants took a photo of each object as a whole, they remembered fewer objects and remembered fewer details about the objects and the objects' locations in the museum than if they instead only observed the objects and did not photograph them. However, when participants zoomed in to photograph a specific part of the object, their subsequent recognition and detail memory was not impaired, and, in fact, memory for features that were not zoomed in on was just as strong as memory for features that were zoomed in on. This finding highlights key differences between people’s memory and the camera’s “memory” and suggests that the additional attentional and cognitive processes engaged by this focused activity can eliminate the photo-taking-impairment effect.
Retinoblastoma is the most common primary intraocular tumor in children. The first sign that is often reported by parents is the appearance of recurrent leukocoria (i.e., “white eye”) in recreational photographs. A quantitative definition or scale of leukocoria - as it appears during recreational photography - has not been established, and the amount of clinical information contained in a leukocoric image (collected by a parent) remains unknown. Moreover, the hypothesis that photographic leukocoria can be a sign of early stage retinoblastoma has not been tested for even a single patient. This study used commercially available software (Adobe Photoshop®) and standard color space conversion algorithms (operable in Microsoft Excel®) to quantify leukocoria in actual “baby pictures” of 9 children with retinoblastoma (that were collected by parents during recreational activities i.e., in nonclinical settings). One particular patient with bilateral retinoblastoma (“Patient Zero”) was photographed >7, 000 times by his parents (who are authors of this study) over three years: from birth, through diagnosis, treatment, and remission. This large set of photographs allowed us to determine the longitudinal and lateral frequency of leukocoria throughout the patient’s life. This study establishes: (i) that leukocoria can emerge at a low frequency in early-stage retinoblastoma and increase in frequency during disease progression, but decrease upon disease regression, (ii) that Hue, Saturation and Value (i.e., HSV color space) are suitable metrics for quantifying the intensity of retinoblastoma-linked leukocoria; (iii) that different sets of intraocular retinoblastoma tumors can produce distinct leukocoric reflections; and (iv) the Saturation-Value plane of HSV color space represents a convenient scale for quantifying and classifying pupillary reflections as they appear during recreational photography.
To recognize that a picture is a representation of a real-life object is a cognitively demanding task. It requires an organism to mentally represent the concrete object (the picture) and abstract its relation to the item that it represents. This form of representational insight has been shown in a small number of mammal and bird species. However, it has not previously been studied in reptiles. This study examined picture-object recognition in the red-footed tortoise (Chelonoidis carbonaria). In Experiment 1, five red-footed tortoises were trained to distinguish between food and non-food objects using a two-alternative forced choice procedure. After reaching criterion, they were presented with test trials in which the real objects were replaced with color photographs of those objects. There was no difference in performance between training and test trials, suggesting that the tortoises did see some correspondence between the real object and its photographic representation. Experiment 2 examined the nature of this correspondence by presenting the tortoises with a choice between the real food object and a photograph of it. The findings revealed that the tortoises confused the photograph with the real-life object. This suggests that they process real items and photographic representations of these items in the same way and, in this context, do not exhibit representational insight.
Beginning in the late 1870s, before the invention of movie cameras or projectors, pioneering English American photographer Eadweard Muybridge photographed iconic image sequences of people and animals in motion using arrays of sequentially triggered single-image cameras. In 1885, Philadelphia neurologist Francis Dercum initiated a collaborative relationship with Muybridge at the University of Pennsylvania to photograph sequential images of patients with various neurologic disorders of movement, including an acquired pathologic quadrupedal gait in a young boy that developed as a consequence of poliomyelitis.
How does volitional photo taking affect unaided memory for visual and auditory aspects of experiences? Across one field and three lab studies, we found that, even without revisiting any photos, participants who could freely take photographs during an experience recognized more of what they saw and less of what they heard, compared with those who could not take any photographs. Further, merely taking mental photos had similar effects on memory. These results provide support for the idea that photo taking induces a shift in attention toward visual aspects and away from auditory aspects of an experience. Additional findings were in line with this mechanism: Participants with a camera had better recognition of aspects of the scene that they photographed than of aspects they did not photograph. Furthermore, participants who used a camera during their experience recognized even nonphotographed aspects better than participants without a camera did. Meta-analyses including all reported studies support these findings.
People with autism spectrum disorder (ASD) show atypical attention to social stimuli  and gaze at faces  and complex images  in unusual ways. But all studies to date are limited by the experimenter’s selected stimuli, which are generally photographs taken by people without autism. What might participants with ASD show us if they were the ones taking the photos? We gave participants a digital camera and analysed the photos they took: images taken by participants with ASD had unusual features and showed strikingly different ways of photographing other people.
Many commercial as well as custom-built fluorescence microscopes use scientific-grade cameras that represent a substantial share of the instrument’s cost. This holds particularly true for super-resolution localization microscopy where high demands are placed especially on the detector with respect to sensitivity, noise, and also image acquisition speed. Here, we present and carefully characterize an industry-grade CMOS camera as a cost-efficient alternative to commonly used scientific cameras. Direct experimental comparison of these two detector types shows widely similar performance for imaging by single molecule localization microscopy (SMLM). Furthermore, high image acquisition speeds are demonstrated for the CMOS detector by ultra-fast SMLM imaging.
An article recently published in this journal (Cox, Devine, Bischmann, & Hyde, 2016) questioned the validity of existing research on the accurate judgment of sexual orientation from photographs of faces. Specifically, those authors reported a confound in their stimuli whereby the photos of sexual minorities (gay men and lesbians) were of higher quality than the photos of heterosexuals. Based on this finding, they concluded that the accuracy in judging sexual orientation from faces demonstrated in the broader literature is an artifact of stimulus quality differences. Here, we addressed this claim by systematically testing the numerous photo sets that we have used in 61 studies documenting accurate judgments of sexual orientation from facial cues published since 2007. Contrary to their claim, the overwhelming majority of studies (93%) showed no significant differences in photo quality according to sexual orientation. Of those that did show differences, most revealed that heterosexual targets' photos were actually of higher quality than sexual minority targets' photos - opposite of what Cox et al. found. In addition, we highlight additional research using stimuli equated for quality differences overlooked in the recent article by Cox et al., lending further support to the conclusion that sexual orientation is legible from multiple sensory cues.