The effect of a secondary task on drivers' gap acceptance and situational awareness at junctions.

The current studies explored the roles of the visuospatial and phonological working memory subsystems on drivers' gap acceptance and memory for approaching vehicles at junctions. Drivers' behaviour was measured in a high-fidelity driving simulator when at a junction, with, and without a visuospatial or phonological load. When asked to judge when to advance across the junction, gap acceptance thresholds, memory for vehicles and eye movements were not different when there was a secondary task compared to control. However, drivers' secondary task performance was more impaired in the visuospatial than phonological domain. These findings suggest that drivers were able to accept impairment in the secondary task while maintaining appropriate safety margins and situational awareness. These findings can inform the development of in-car technologies, improving the safety of road users at junctions. Practitioner summary: Despite research indicating that concurrent performance on working memory tasks impairs driving, a matched visuospatial or phonological memory load did not change drivers' gap acceptance or situational awareness at junctions. Drivers displayed appropriate compensatory behaviour by prioritising the driving task over the visuospatial secondary task. Abbreviations: ROW: right of way; RIG: random time interval generation.

Visual search in depth: The neural correlates of segmenting a display into relevant and irrelevant three-dimensional regions.

Visual perception is facilitated by the ability to selectively attend to relevant parts of the world and to ignore irrelevant regions or features. In visual search tasks, viewers are able to segment displays into relevant and irrelevant items based on a number of factors including the colour, motion, and temporal onset of the target and distractors. Understanding the process by which viewers prioritise relevant parts of a display can provide insights into the effect of top-down control on visual perception. Here, we investigate the behavioural and neural correlates of segmenting a display according to the expected three-dimensional (3D) location of a target. We ask whether this segmentation is based on low-level visual features (e.g. common depth or common surface) or on higher-order representations of 3D regions. Similar response-time benefits and neural activity were obtained when items fell on common surfaces or within depth-defined volumes, and when displays were vertical (such that items shared a common depth/disparity) or were tilted in depth. These similarities indicate that segmenting items according to their 3D location is based on attending to a 3D region, rather than a specific depth or surface. Segmenting the items in depth was mainly associated with increased activation in depth-sensitive parietal regions rather than in depth-sensitive visual regions. We conclude that segmenting items in depth is primarily achieved via higher-order, cue invariant representations rather than through filtering in lower-level perceptual regions.

Examining evidence for behavioural mimicry of parental eating by adolescent females. An observational study.

Behavioural mimicry is a potential mechanism explaining why adolescents appear to be influenced by their parents' eating behaviour. In the current study we examined whether there is evidence that adolescent females mimic their parents when eating. Videos of thirty-eight parent and female adolescent dyads eating a lunchtime meal together were examined. We tested whether a parent placing a food item into their mouth was associated with an increased likelihood that their adolescent child would place any food item (non-specific mimicry) or the same item (specific mimicry) in their mouth at three different time frames, namely, during the same second or within the next fifteen seconds (+15), five seconds (+5) or two second (+2) period. Parents and adolescents' overall food intake was positively correlated, whereby a parent eating a larger amount of food was associated with the adolescent eating a larger meal. Across all of the three time frames adolescents were more likely to place a food item in their mouth if their parent had recently placed that same food item in their mouth (specific food item mimicry); however, there was no evidence of non-specific mimicry. This observational study suggests that when eating in a social context there is evidence that adolescent females may mimic their parental eating behaviour, selecting and eating more of a food item if their parent has just started to eat that food.

Visual effects on tactile texture perception.

How does vision affect active touch in judgments of surface roughness? We contrasted direct (combination of visual with tactile sensory information) and indirect (vision alters the processes of active touch) effects of vision on touch. Participants judged which of 2 surfaces was rougher using their index finger to make static contact with gratings of spatial period 1580 and 1620 µm. Simultaneously, they viewed the stimulus under one of five visual conditions: No vision, Filtered vision + touch, Veridical vision + touch (where vision alone yielded roughness discrimination at chance), Congruent vision + touch, Incongruent vision + touch. Results from 32 participants showed roughness discrimination for touch with vision was better than touch alone. The visual benefit for touch was strongest in a filtered (spatially non-informative) vision condition, thus results are interpreted in terms of indirect integration. An indirect effect of vision was further indicated by a finding of visual benefit in some but not all visuo-tactile congruency conditions.

Older adults do not show enhanced benefits from multisensory information on speeded perceptual discrimination tasks.

Some research has shown that older adults benefit more from multisensory information than do young adults. However, more recent evidence has shown that the multisensory age benefit varies considerably across tasks. In the current study, older (65 - 80) and young (18 - 30) adults (N = 191) completed a speeded perceptual discrimination task either online or face-to-face to assess task response speed. We examined whether presenting stimuli in multiple sensory modalities (audio-visual) instead of one (audio-only or visual-only) benefits older adults more than young adults. Across all three experiments, a consistent speeding of response was found in the multisensory condition compared to the unisensory conditions for both young and older adults. Furthermore, race model analysis showed a significant multisensory benefit across a broad temporal interval. Critically, there were no significant differences between young and older adults. Taken together, these findings provide strong evidence in favour of a multisensory benefit that does not differ across age groups, contrasting with prior research.

Age Deficits in Associative Memory Are Not Alleviated by Multisensory Paradigms.

OBJECTIVES: Age deficits in memory are widespread, this affects individuals at a personal level, and investigating memory has been a key focus in cognitive aging research. Age deficits occur in memory for an episode, where information from the environment is integrated through the senses into an episodic event via associative memory. Associating items in memory has been shown to be particularly difficult for older adults but can often be alleviated by providing support from the external environment. The current investigation explored the potential for increased sensory input (multimodal stimuli) to alleviate age deficits in associative memory. Here, we present compelling evidence, supported by Bayesian analysis, for a null age-by-modality interaction. METHODS: Across three preregistered studies, young and older adults (n = 860) completed associative memory tasks either in single modalities or in multimodal formats. Study 1 used either visual text (unimodal) or video introductions (multimodal) to test memory for name-face associations. Studies 2 and 3 tested memory for paired associates. Study 2 used unimodal visual presentation or cross-modal visual-auditory word pairs in a cued recall paradigm. Study 3 presented word pairs as visual only, auditory only, or audiovisual and tested memory separately for items (individual words) or associations (word pairings). RESULTS: Typical age deficits in associative memory emerged, but these were not alleviated by multimodal presentation. DISCUSSION: The lack of multimodal support for associative memory indicates that perceptual manipulations are less effective than other forms of environmental support at alleviating age deficits in associative memory.

Terms of debate: Consensus definitions to guide the scientific discourse on visual distraction.

Hypothesis-driven research rests on clearly articulated scientific theories. The building blocks for communicating these theories are scientific terms. Obviously, communication - and thus, scientific progress - is hampered if the meaning of these terms varies idiosyncratically across (sub)fields and even across individual researchers within the same subfield. We have formed an international group of experts representing various theoretical stances with the goal to homogenize the use of the terms that are most relevant to fundamental research on visual distraction in visual search. Our discussions revealed striking heterogeneity and we had to invest much time and effort to increase our mutual understanding of each other's use of central terms, which turned out to be strongly related to our respective theoretical positions. We present the outcomes of these discussions in a glossary and provide some context in several essays. Specifically, we explicate how central terms are used in the distraction literature and consensually sharpen their definitions in order to enable communication across theoretical standpoints. Where applicable, we also explain how the respective constructs can be measured. We believe that this novel type of adversarial collaboration can serve as a model for other fields of psychological research that strive to build a solid groundwork for theorizing and communicating by establishing a common language. For the field of visual distraction, the present paper should facilitate communication across theoretical standpoints and may serve as an introduction and reference text for newcomers.

Eye movements are made to the centre of gravity of texture-defined targets.

Saccadic localisation of targets of various properties has been extensively studied, but rarely for texture-defined figures. In this paper, three experiments that investigate the way information from a texture target is processed in order to provide a signal for eye movement control are presented. Participants made saccades to target regions embedded in a background structure, and the saccade landing position and latency were measured. The textures comprised line elements, with orientations of the lines configured to form the figure and ground. Various orientation profile configurations (Block, Blur, and Cornsweet), were used in order to measure the role of edge profiles in driving eye movements and producing salience. We found that in all cases the visual system is in fact able to effectively segregate a texture figure from the ground in order to accurately plan a saccade to the target-figure. While saccadic latency was the highest for the Blur profile, the mean saccadic landing position was mostly unaffected by the various profiles (Experiment 1). More specifically, we showed that saccades were directed to the centre-of-gravity of the target (Experiment 2). We also found that figures with information of orientation contrast at both the edge and centre of figure (i.e. Block) produced the highest level of saliency in attracting eye movements (Experiment 3). Overall, the results show that saccades are planned on the representation of the whole target shape rather than a local salient region based on orientation contrast cues, and that the various texture profiles were important only to the extent that they affected the time to programme a saccade.

The effect of unisensory and multisensory information on lexical decision and free recall in young and older adults.

Studies using simple low-level stimuli show that multisensory stimuli lead to greater improvements in processing speed for older adults than young adults. However, there is insufficient evidence to explain how these benefits influence performance for more complex processes such as judgement and memory tasks. This study examined how presenting stimuli in multiple sensory modalities (audio-visual) instead of one (audio-only or visual-only) may help older adults to improve their memory and cognitive processing compared to young adults. Young and older adults completed lexical decision (real word vs. pseudoword judgement) and word recall tasks, either independently, or in combination (dual-task), with and without perceptual noise. Older adults were better able to remember words when encoding independently. In contrast, young adults were better able to remember words when encoding in combination with lexical decisions. Both young and older adults had better word recall in the audio-visual condition compared with the audio-only condition. The findings indicate significant age differences when dealing with multiple tasks during encoding. Crucially, there is no greater multisensory benefit for older adults compared to young adults in more complex processes, rather multisensory stimuli can be useful in enhancing cognitive performance for both young and older adults.

Evidence for vibration coding of sliding tactile textures in auditory cortex.

Introduction: Psychophysical studies suggest texture perception is mediated by spatial and vibration codes (duplex theory). Vibration coding, driven by relative motion between digit and stimulus, is involved in the perception of very fine gratings whereas coarse texture perception depends more on spatial coding, which does not require relative motion. Methods: We examined cortical activation, using functional Magnetic Resonance Imaging associated with fine and coarse tactile spatial gratings applied by sliding or touching (sliding vs. static contact) on the index finger pad. Results: We found regions, contralateral to the stimulated digit, in BA1 in S1, OP1, OP3, and OP4 in S2, and in auditory cortex, which were significantly more activated by sliding gratings but did not find this pattern in visual cortex. Regions in brain areas activated by vibrotactile stimuli (including auditory cortex) were also modulated by whether or not the gratings moved. In a control study we showed that this contrast persisted when the salience of the static condition was increased by using a double touch. Discussion: These findings suggest that vibration from sliding touch invokes multisensory cortical mechanisms in tactile processing of roughness. However, we did not find evidence of a separate visual region activated by static touch nor was there a dissociation between cortical response to fine vs. coarse gratings as might have been expected from duplex theory.

Similar behaviour, different brain patterns: age-related changes in neural signatures of ignoring.

We measured behavioural performance and fMRI activity whilst old and young adults performed a temporal segmentation task ('preview search'). Being able to select parts of the visual world to be attended or ignored is a critical visual skill. Both old and young adults were able to improve their performance on a difficult search task when some of the distracter items were presented earlier than the remainder. Comparisons of brain activity and functional connectivity, however, suggested that the underlying mechanisms are quite different for the two age groups. Older adults' activation patterns do not correspond to those predicted by simple increased involvement of frontal regions reflecting higher demand with age but seem to suggest that changes in brain activation patterns propagate throughout the cortex.

Impaired attentional selection following lesions to human pulvinar: evidence for homology between human and monkey.

We examined the contributions of the human pulvinar to goal directed selection of visual targets in 3 patients with chronic, unilateral lesions involving topographic maps in the ventral pulvinar. Observers completed 2 psychophysical tasks in which they discriminated the orientation of a lateralized target grating in the presence of vertically-aligned distracters. In experiment 1, where distracter contrast was varied while target contrast remained constant, the patients' contralesional contrast thresholds for discriminating the orientation of grating stimuli were elevated only when the task required selection of a visual target in the face of competition from a salient distracter. Attentional selectivity was restored in the patients in experiment 2 where target contrast was varied while distracter contrast remained constant. These observations provide the first evidence that the human pulvinar plays a necessary role in modulating physical saliency in attentional selection, and supports a homology in global pulvinar structure between humans and monkey.

Endogenous control is insufficient for preventing attentional capture in children and adults.

Adults are known to have developed the ability to selectively focus their attention in a goal-driven (endogenous) manner but it is less clear at what stage in development (5-6 & 9-11 years) children can endogenously control their attention and whether they behave similarly to adults when managing distractions. In this study we administered a child-adapted cued visual search task to three age-groups: five- to six-year-olds (N = 45), nine- to eleven-year-olds (N = 42) and adults (N = 42). Participants were provided with a cue which either guided their attention towards or away from an upcoming target. On some trials, a singleton distracter was presented which participants needed to ignore. Participants completed three conditions where the cues were: 1) usually helpful (High Predictive), 2) usually unhelpful (Low Predictive) and 3) never helpful (Baseline) in guiding attention towards the target. We found that endogenous cue-utilisation develops with increasing age. Overall, nine- to eleven-year-olds and adults, but not five- to six-year-olds, utilised the endogenous cues in the High Predictive condition. However, all age-groups were unable to ignore the singleton distracter even when using endogenous control. Moreover, we found better cue-maintenance ability was related to poorer distracter-inhibition ability in early-childhood, but these skills were no longer related further on in development. We conclude that overall endogenous control is still developing in early-childhood, but an adult-like form of this skill has been acquired by mid-childhood. Furthermore, endogenous cue-utilisation was shown as insufficient for preventing attentional capture in both children and adults.

Does audio-visual information result in improved health-related decision-making compared with audio-only or visual-only information? Protocol for a systematic review and meta-analysis.

INTRODUCTION: Making health-related decisions can be difficult due to the amount and complexity of information available. Audio-visual information may improve memory for health information but whether audio-visual information can enhance health-related decisions has not been explored using quantitative methods. The objective of this systematic review is to understand how effective audio-visual information is for informing health-related decision-making compared with audio-only or visual-only information. METHODS AND ANALYSIS: Randomised controlled trials (RCTs) will be included if they include audio-visual and either audio-only or visual-only information provision and decision-making in a health setting. Studies will be excluded if they are not reported in English. Twelve databases will be searched including: Ovid MEDLINE, PubMed and PsychINFO. The Cochrane Risk of Bias tool (V.7) will be used to assess risk of bias in included RCTs. Results will be synthesised primarily using a meta-analysis; where quantitative data are not reported, a narrative synthesis will be used. ETHICS AND DISSEMINATION: No ethical issues are foreseen. Data will be disseminated via academic publication and conference presentations. Findings may also be published in scientific newsletters and magazines. This review is funded by the Economic and Social Research Council. PROSPERO REGISTRATION NUMBER: CRD42021255725.

Active ignoring in early visual cortex.

Selective attention is critical for controlling the input to mental processes. Attentional mechanisms act not only to select relevant stimuli but also to exclude irrelevant stimuli. There is evidence that we can actively ignore irrelevant information. We measured neural activity relating to successfully ignoring distracters (using preview search) and found increases in both the precuneus and primary visual cortex during preparation to ignore distracters. We also found reductions in activity in fronto-parietal regions while previewing distracters and a reduction in activity in early visual cortex during search when a subset of items was successfully excluded from search, both associated with precuneus activity. These results are consistent with the proposal that actively excluding distractions has two components: an initial stage where distracters are encoded, and a subsequent stage where further processing of these items is inhibited. Our findings suggest that it is the precuneus that controls this process and can modulate activity in visual cortex as early as V1.

Decomposing the neural mechanisms of visual search through model-based analysis of fMRI: top-down excitation, active ignoring and the use of saliency by the right TPJ.

Despite being studied intensively over the past 30 years, the neural processes underlying visual search are not yet fully understood. In the current study we extend prior work using model-based analysis to decompose fMRI data. fMRI data on human search were assessed using activation functions predicted from the spiking Search over Time and Space model (sSoTS; Mavritsaki et al., 2006). Going beyond previous work, we show for the first time that activity in a central location map in the model, which computes the saliency of a target relative to distractors, correlated with the BOLD response in the right temporo-parietal junction (TPJ)--a key region implicated in clinical studies of unilateral neglect. This is consistent with the right TPJ responding to the relative saliency of visual stimuli. In addition, a re-analysis of search performance, with a larger participant set and a psychologically plausible response rule, showed distinct neural regions in parietal and occipital cortices linked to top-down excitation and the to active ignoring of distractors. The results indicate that excitatory and inhibitory circuits for visual selection can be separated, and that the right TPJ may be critical for responding to salient targets. The value of using a model-based approach is discussed.

The role of contrast sensitivity in global motion processing deficits in the elderly.

This study compared the effects of age on the perception of translational, radial, and rotational global motion patterns. Motion coherence thresholds were measured for judging the direction of each motion type as a function of contrast (visibility) and temporal sampling rate in young and elderly participants. Coherence thresholds decreased as dot contrast increased asymptoting at high dot contrasts but were higher in elderly compared to young participants. This equated to global motion impairment in the elderly of a factor of around 2, characterized by a shift of the threshold vs. contrast function along the horizontal axes (dot contrast). The effect of contrast interacted with the temporal sampling rate. Old participants were deleteriously affected by reduced temporal sampling particularly at low contrasts. The findings suggest that age-related changes in global motion perception may be driven principally by deficits in contrast encoding, rather than by deficits in motion integration and suggest a role for increased internal noise in the older visual system.

Contact forces in roughness discrimination.

Roughness perception through fingertip contact with a textured surface can involve spatial and temporal cues from skin indentation and vibration respectively. Both types of cue may be affected by contact forces when feeling a surface and we ask whether, on a given trial, discrimination performance relates to contact forces. We examine roughness discrimination performance in a standard psychophysical method (2-interval forced choice, in which the participant identifies which of two spatial textures formed by parallel grooves feels rougher) while continuously measuring the normal and tangential forces applied by the index finger. Fourteen participants discriminated spatial gratings in fine (spatial period of 320-580 micron) and coarse (1520-1920 micron) ranges using static pressing or sliding contact of the index finger. Normal contact force (mean and variability) during pressing or sliding had relatively little impact on accuracy of roughness judgments except when pressing on surfaces in the coarse range. Discrimination was better for sliding than pressing in the fine but not the coarse range. In contrast, tangential force fluctuations during sliding were strongly related to roughness judgment accuracy.

Ventral extra-striate cortical areas are required for human visual texture segmentation.

A patient (HJA) with bilateral occipital lobe damage to ventral cortical areas V2, V3 and V4 was tested on a texture segmentation task involving texture bar detection in an array of oriented lines. Performance detecting a target shape was assessed as the orientations of the background lines had increasing orientation noise. Control participants found the task easier when the background lines had the same orientation or only slightly shifted in orientation. HJA was poor with all backgrounds but particularly so when the background lines had the same or almost the same orientations. The results suggest that V1 alone is not sufficient to perform easy texture segmentation, even when the background of the display is a homogeneous texture. Ventral extra-striate cortical areas are needed in order to detect texture boundaries. We suggest that extra-striate visual areas enhance the borders between the target and background, while also playing a role in reducing the signal from homogeneous texture backgrounds.

Comparing drivers' visual attention at Junctions in Real and Simulated Environments.

Driving simulation is widely used to answer important applied research questions, however, it is vital for specific driving tasks to undergo appropriate behavioural validation testing. Many previous validation studies have used simple driving tasks and measured relatively low-level vehicle control. The purpose of the current study was to investigate whether drivers' visual attention at intersections with different levels of demand, are similar in the simulator and on the road. Unlike simpler driving tasks, crossing intersections requires complex interactions with other vehicles governed by sequences of head and eye movements that may not be accurately captured in a simulated environment. In the current study we directly compare performance at simulated junctions with the same participants' behaviour in a real car. We compared drivers' visual attention in a high-fidelity driving simulator (instrumented car, 360-degree screen) and on-road in both low and medium demand driving situations. The low and medium demand driving situations involved the same motor movements, containing straight on, right turn and left turn manoeuvres. The low demand situations were controlled by the road environment and traffic lights, whereas medium demand situations required the driver to scan the environment and decide when it was safe to pull out into the junction. Natural junctions in Nottingham were used for the on-road phase and the same junctions were recreated in the simulator with traffic levels matched to those that were encountered on the real roads. The frequency and size of drivers' head movements were not significantly different between manoeuvres performed in the simulator and those conducted when driving on real roads. This suggests that drivers' broad search strategies in the simulator are representative of real-world driving. These strategies did change as a function of task demand - compared to low demand situations, behaviour at the medium demand junctions was characterised by longer junction crossing times, more head movements, shorter fixation durations and larger saccadic amplitudes. Although patterns of head movements were equivalent on road and in the simulator, there were differences in more fine-grained measures of eye-movements. Mean fixation durations were longer in the simulator compared to on-road, particularly in low-demand situations. We interpret this as evidence for lower levels of visual engagement with the simulated environment compared to the real world, at least when the task demands are low. These results have important implications for driving research. They suggest that high fidelity driving simulators can be useful tools for investigating drivers' visual attention at junctions, particularly when the driving task is of at least moderate demand.