Cognitive and neuroscientific perspectives of healthy ageing.

With dementia incidence projected to escalate significantly within the next 25 years, the United Nations declared 2021-2030 the Decade of Healthy Ageing, emphasising cognition as a crucial element. As a leading discipline in cognition and ageing research, psychology is well-equipped to offer insights for translational research, clinical practice, and policy-making. In this comprehensive review, we discuss the current state of knowledge on age-related changes in cognition and psychological health. We discuss cognitive changes during ageing, including (a) heterogeneity in the rate, trajectory, and characteristics of decline experienced by older adults, (b) the role of cognitive reserve in age-related cognitive decline, and (c) the potential for cognitive training to slow this decline. We also examine ageing and cognition through multiple theoretical perspectives. We highlight critical unresolved issues, such as the disparate implications of subjective versus objective measures of cognitive decline and the insufficient evaluation of cognitive training programs. We suggest future research directions, and emphasise interdisciplinary collaboration to create a more comprehensive understanding of the factors that modulate cognitive ageing.

A guide to measuring expert performance in forensic pattern matching.

Decisions in forensic science are often binary. A firearms expert must decide whether a bullet was fired from a particular gun or not. A face comparison expert must decide whether a photograph matches a suspect or not. A fingerprint examiner must decide whether a crime scene fingerprint belongs to a suspect or not. Researchers who study these decisions have therefore quantified expert performance using measurement models derived largely from signal detection theory. Here we demonstrate that the design and measurement choices researchers make can have a dramatic effect on the conclusions drawn about the performance of forensic examiners. We introduce several performance models - proportion correct, diagnosticity ratio, and parametric and non-parametric signal detection measures - and apply them to forensic decisions. We use data from expert and novice fingerprint comparison decisions along with a resampling method to demonstrate how experimental results can change as a function of the task, case materials, and measurement model chosen. We also graphically show how response bias, prevalence, inconclusive responses, floor and ceiling effects, case sampling, and number of trials might affect one's interpretation of expert performance in forensics. Finally, we discuss several considerations for experimental and diagnostic accuracy studies: (1) include an equal number of same-source and different-source trials; (2) record inconclusive responses separately from forced choices; (3) include a control comparison group; (4) counterbalance or randomly sample trials for each participant; and (5) present as many trials to participants as is practical.

The effect of fingerprint expertise on visual short-term memory.

Expert fingerprint examiners demonstrate impressive feats of memory that may support their accuracy when making high-stakes identification decisions. Understanding the interplay between expertise and memory is therefore critical. Across two experiments, we tested fingerprint examiners and novices on their visual short-term memory for fingerprints. In Experiment 1, experts showed substantially higher memory performance compared to novices for fingerprints from their domain of expertise. In Experiment 2, we manipulated print distinctiveness and found that while both groups benefited from distinctive prints, experts still outperformed novices. This indicates that beyond stimulus qualities, expertise itself enhances short-term memory, likely through more effective organisational processing and sensitivity to meaningful patterns. Taken together, these findings shed light on the cognitive mechanisms that may explain fingerprint examiners' superior memory performance within their domain of expertise. They further suggest that training to improve memory for diverse fingerprints could practically boost examiner performance. Given the high-stakes nature of forensic identification, characterising psychological processes like memory that potentially contribute to examiner accuracy has important theoretical and practical implications.

An evidence accumulation model of perceptual discrimination with naturalistic stimuli.

Evidence accumulation models have been used to describe the cognitive processes underlying performance in tasks involving 2-choice decisions about unidimensional stimuli, such as motion or orientation. Given the multidimensionality of natural stimuli, however, we might expect qualitatively different patterns of evidence accumulation in more applied perceptual tasks. One domain that relies heavily on human decisions about complex natural stimuli is fingerprint discrimination. We know little about the ability of evidence accumulation models to account for the dynamic decision process of a fingerprint examiner resolving if 2 different prints belong to the same finger or different fingers. Here, we apply a dynamic decision-making model-the linear ballistic accumulator (LBA)-to fingerprint discrimination decisions to gain insight into the cognitive processes underlying these complex perceptual judgments. Across 3 experiments, we show that the LBA provides an accurate description of the fingerprint discrimination decision process with manipulations in visual noise, speed-accuracy emphasis, and training. Our results demonstrate that the LBA is a promising model for furthering our understanding of applied decision-making with naturally varying visual stimuli. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

How low can you go? Detecting style in extremely low resolution images.

Humans can see through the complexity of scenes, faces, and objects by quickly extracting their redundant low-spatial and low-dimensional global properties, or their style. It remains unclear, however, whether semantic coding is necessary, or whether visual stylistic information is sufficient, for people to recognize and discriminate complex images and categories. In two experiments, we systematically reduce the resolution of hundreds of unique paintings, birds, and faces, and test people's ability to discriminate and recognize them. We show that the stylistic information retained at extremely low image resolutions is sufficient for visual recognition of images and visual discrimination of categories. Averaging over the 3 domains, people were able to reliably recognize images reduced down to a single pixel, with large differences from chance discriminability across 8 different image resolutions. People were also able to discriminate categories substantially above chance with an image resolution as low as 2 × 2 pixels. We situate our findings in the context of contemporary computational accounts of visual recognition and contend that explicit encoding of the local features in the image, or knowledge of the semantic category, is not necessary for recognizing and distinguishing complex visual stimuli. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Thinking forensics: Cognitive science for forensic practitioners.

Human factors and their implications for forensic science have attracted increasing levels of interest across criminal justice communities in recent years. Initial interest centred on cognitive biases, but has since expanded such that knowledge from psychology and cognitive science is slowly infiltrating forensic practices more broadly. This article highlights a series of important findings and insights of relevance to forensic practitioners. These include research on human perception, memory, context information, expertise, decision-making, communication, experience, verification, confidence, and feedback. The aim of this article is to sensitise forensic practitioners (and lawyers and judges) to a range of potentially significant issues, and encourage them to engage with research in these domains so that they may adapt procedures to improve performance, mitigate risks and reduce errors. Doing so will reduce the divide between forensic practitioners and research scientists as well as improve the value and utility of forensic science evidence.

Image toggling saves time in mammography.

When two images are perfectly aligned, even subtle differences are readily detected when the images are "toggled" back and forth in the same location. However, substantial changes between two photographs can be missed if the images are misaligned ("change blindness"). Nevertheless, recent work from our lab, testing nonradiologists, suggests that toggling misaligned photographs leads to superior performance compared to side-by-side viewing (SBS). In order to determine if a benefit of toggling misaligned images may be observed in clinical mammography, we developed an image toggling technique where pairs of new and prior breast imaging exam images could be efficiently toggled back and forth. Twenty-three radiologists read 10 mammograms evenly divided in toggle and SBS modes. The toggle mode led to a 6-s benefit in reaching a decision [[Formula: see text], [Formula: see text]]. The toggle viewing mode also led to a 5% improvement in diagnostic accuracy, though in our small sample this effect was not statistically reliable. Time savings were found even though successive mammograms were not perfectly aligned. Given the ever-increasing caseload for radiologists, this simple manipulation of how the images are viewed could save valuable time in clinical practice, allowing radiologists to read more cases or spend more time on difficult cases.

The nature of expertise in fingerprint matching: experts can do a lot with a little.

Expert decision making often seems impressive, even miraculous. People with genuine expertise in a particular domain can perform quickly and accurately, and with little information. In the series of experiments presented here, we manipulate the amount of "information" available to a group of experts whose job it is to identify the source of crime scene fingerprints. In Experiment 1, we reduced the amount of information available to experts by inverting fingerprint pairs and adding visual noise. There was no evidence for an inversion effect-experts were just as accurate for inverted prints as they were for upright prints-but expert performance with artificially noisy prints was impressive. In Experiment 2, we separated matching and nonmatching print pairs in time. Experts were conservative, but they were still able to discriminate pairs of fingerprints that were separated by five-seconds, even though the task was quite different from their everyday experience. In Experiment 3, we separated the print pairs further in time to test the long-term memory of experts compared to novices. Long-term recognition memory for experts and novices was the same, with both performing around chance. In Experiment 4, we presented pairs of fingerprints quickly to experts and novices in a matching task. Experts were more accurate than novices, particularly for similar nonmatching pairs, and experts were generally more accurate when they had more time. It is clear that experts can match prints accurately when there is reduced visual information, reduced opportunity for direct comparison, and reduced time to engage in deliberate reasoning. These findings suggest that non-analytic processing accounts for a substantial portion of the variance in expert fingerprint matching accuracy. Our conclusion is at odds with general wisdom in fingerprint identification practice and formal training, and at odds with the claims and explanations that are offered in court during expert testimony.

Human matching performance of genuine crime scene latent fingerprints.

There has been very little research into the nature and development of fingerprint matching expertise. Here we present the results of an experiment testing the claimed matching expertise of fingerprint examiners. Expert (n = 37), intermediate trainee (n = 8), new trainee (n = 9), and novice (n = 37) participants performed a fingerprint discrimination task involving genuine crime scene latent fingerprints, their matches, and highly similar distractors, in a signal detection paradigm. Results show that qualified, court-practicing fingerprint experts were exceedingly accurate compared with novices. Experts showed a conservative response bias, tending to err on the side of caution by making more errors of the sort that could allow a guilty person to escape detection than errors of the sort that could falsely incriminate an innocent person. The superior performance of experts was not simply a function of their ability to match prints, per se, but a result of their ability to identify the highly similar, but nonmatching fingerprints as such. Comparing these results with previous experiments, experts were even more conservative in their decision making when dealing with these genuine crime scene prints than when dealing with simulated crime scene prints, and this conservatism made them relatively less accurate overall. Intermediate trainees-despite their lack of qualification and average 3.5 years experience-performed about as accurately as qualified experts who had an average 17.5 years experience. New trainees-despite their 5-week, full-time training course or their 6 months experience-were not any better than novices at discriminating matching and similar nonmatching prints, they were just more conservative. Further research is required to determine the precise nature of fingerprint matching expertise and the factors that influence performance. The findings of this representative, lab-based experiment may have implications for the way fingerprint examiners testify in court, but what the findings mean for reasoning about expert performance in the wild is an open, empirical, and epistemological question.

Expertise in fingerprint identification.

Although fingerprint experts have presented evidence in criminal courts for more than a century, there have been few scientific investigations of the human capacity to discriminate these patterns. A recent latent print matching experiment shows that qualified, court-practicing fingerprint experts are exceedingly accurate (and more conservative) compared with novices, but they do make errors. Here, a rationale for the design of this experiment is provided. We argue that fidelity, generalizability, and control must be balanced to answer important research questions; that the proficiency and competence of fingerprint examiners are best determined when experiments include highly similar print pairs, in a signal detection paradigm, where the ground truth is known; and that inferring from this experiment the statement "The error rate of fingerprint identification is 0.68%" would be unjustified. In closing, the ramifications of these findings for the future psychological study of forensic expertise and the implications for expert testimony and public policy are considered.

Flashed face distortion effect: grotesque faces from relative spaces.

We describe a novel face distortion effect resulting from the fast-paced presentation of eye-aligned faces. When cycling through the faces on a computer screen, each face seems to become a caricature of itself and some faces appear highly deformed, even grotesque. The degree of distortion is greatest for faces that deviate from the others in the set on a particular dimension (eg if a person has a large forehead, it looks particularly large). This new method of image presentation, based on alignment and speed, could provide a useful tool for investigating contrastive distortion effects and face adaptation.

Multisensory integration with a head-mounted display: role of mental and manual load.

OBJECTIVE: The aim of this study was to replicate the finding that multisensory integration with a head-mounted display (HMD) is particularly difficult when a person is walking and hearing sound from a free-field speaker, and to extend the finding with a response method intended to reduce workload. BACKGROUND: HMDs can support the information needs of workers whose work requires mobility, but some low-cost solutions for delivering auditory information may be less effective than others. METHOD: For the study, 24 participants detected whether shapes moving on the HMD screen made a sound appropriate to their forms when they collided with other shapes. Independent variables were self-motion (participants were mobile or seated), sound delivery (free-field speakers or an earpiece), and response method (noting mismatches via a mental count or via a manual clicker). RESULTS: Unexpectedly, overall mismatch task accuracy was worse with the clicker (p = .027) than without. Participants also reported that it was harder to time-share the mismatch task with clicker responses (p = .033). In the clicker condition, self-motion and sound delivery interacted but in the opposite direction to the previous study. CONCLUSION: The best way of delivering auditory information to mobile workers performing a multisensory integration task with an HMD may depend on whether responding involves mental load or manual load. Broader theories are needed to capture factors influencing performance. APPLICATION: Until more powerful theory is developed, designers should perform careful formative and summative tests of whether the activities to be performed by mobile HMD wearers will make some sound delivery solutions less effective than others.

Multisensory integration with a head-mounted display: background visual motion and sound motion.

OBJECTIVE: The aim of this study was to assess how background visual motion and the relative movement of sound affect a head-mounted display (HMD) wearer's performance at a task requiring integration of auditory and visual information. BACKGROUND: HMD users are often mobile. A commercially available speaker in a fixed location delivers auditory information affordably to the HMD user. However, previous research has shown that mobile HMD users perform poorly at tasks that require integration of visual and auditory information when sound comes from a free-field speaker. The specific cause of the poor task performance is unknown. METHOD: Participants counted audiovisual events that required integration of sounds delivered via a free-field speaker and vision on an HMD. Participants completed the task while either walking around a room, sitting in the room, or sitting inside a mobile room that allowed separate manipulation of background visual motion and speaker motion. RESULTS: Participants' accuracy at counting target audiovisual events was worse when participants were walking than when sitting at a desk, p = .032. Compared with when they were sitting at a desk, participants' accuracy at counting target audiovisual events showed a trend to be worse when they experienced a combination of background visual motion and the relative movement of sound, p = .058. CONCLUSION: Multisensory integration performance is least effective when HMD users experience a combination of background visual motion and relative movement of sound. Eye reflexes may play an important role. APPLICATION: Results apply to situations in which HMD wearers are mobile when receiving multimodal information, as in health care and military contexts.

Multisensory integration with a head-mounted display: sound delivery and self-motion.

OBJECTIVE: We tested whether the method of sound delivery affects people's ability to integrate information from multiple modalities when they are walking and using a head-mounted display (HMD). BACKGROUND: HMDs increasingly support mobile work. Human operators may benefit from auditory support when using an HMD. However, it is unclear whether sound is better delivered publicly in free field or privately via earpiece and what the effect of walking is. METHOD: Participants identified mismatches between sounds and visual information on an HMD. Participants heard the sounds via either earpiece or free field while they either sat or walked about the test room. RESULTS: When using an earpiece, participants performed the mismatch task equally well whether sitting or walking, but when using free-field sound, participants performed the task significantly worse when walking than when sitting (p = .006). CONCLUSION: The worse performance for participants using free-field sound while walking may relate to spatial and motion inconsistencies between visual events on the head-referenced HMD and auditory events from world-referenced speakers. Researchers should more frequently examine the effect of self-motion on people's ability to perform various multisensory tasks. APPLICATION: When multisensory integration tasks are performed with an HMD and free-field delivery of sound, as may happen in medicine, transportation, or industry, performance may suffer when the relative location of sound changes as the user moves.