Optimising metameric spectra for integrative lighting to modulate the circadian system without affecting visual appearance

Smart integrative lighting systems aim to support human health and wellbeing by capitalising on the light-induced effects on circadian rhythms, sleep, and cognitive functions, while optimising the light’s visual aspects like colour fidelity, visual comfort, visual preference, and visibility. Metameric spectral tuning could be an instrument to solve potential conflicts between the visual preferences of users with respect to illuminance and chromaticity and the circadian consequences of the light exposure, as metamers can selectively modulate melanopsin-based photoreception without affecting visual properties such as chromaticity or illuminance. This work uses a 6-, 8- and 11-channel LED luminaire with fixed illuminance of 250 lx to systematically investigate the metameric tuning range in melanopic equivalent daylight illuminance (EDI) and melanopic daylight efficacy ratio (melanopic DER) for 561 chromaticity coordinates as optimisation targets (2700 K to 7443 K ± Duv 0 to 0.048), while applying colour fidelity index Rf criteria from the TM-30-20 Annex E recommendations (i.e. Rf$$\ge$$ ≥ 85, Rf,h1$$\ge$$ ≥ 85). Our results reveal that the melanopic tuning range increases with rising CCT to a maximum tuning range in melanopic DER of 0.24 (CCT: 6702 K, Duv: 0.003), 0.29 (CCT: 7443 K, Duv: 0) and 0.30 (CCT: 6702, Duv: 0.006), depending on the luminaire’s channel number of 6, 8 or 11, respectively. This allows to vary the melanopic EDI from 212.5–227.5 lx up to 275–300 lx without changes in the photopic illuminance (250 lx) or chromaticity ($$\Delta u'v'$$ Δ u ′ v ′ $$\le$$ ≤ 0.0014). The highest metameric melanopic Michelson contrast for the 6-, 8- and 11-channel luminaire is 0.16, 0.18 and 0.18, which is accomplished at a CCT of 3017 K (Duv: − 0.018), 3456 K (Duv: 0.009) and 3456 K (Duv: 0.009), respectively. By optimising ~ 490,000 multi-channel LED spectra, we identified chromaticity regions in the CIExy colour space that are of particular interest to control the melanopic efficacy with metameric spectral tuning.

Nearby Pockets for Promoting Students' Social Interaction on Malaysian Campus Ground

Recently, nearby pockets on campus ground have become an important tool to improve academic outcomes by enhancing students’ social-learning activities. However, nearby open spaces and pocket parks of Malaysian universities lack the promotion of social interaction and informal activities that affect the academic experience, especially in the outdoor spaces. Therefore, there is a need to enhance students' social interaction on campus ground in Malaysian universities. This study aims to understand the preferred attributes of nearby pocket parks in Malaysian universities to predict students’ social interaction. This study employed a visual preference survey (VPS) conducted in three Malaysian universities, including Universiti Malaya (UM), Universiti Putra Malaysia (UPM), and Universiti Kebangsaan Malaysia (UKM), to assess the visual preferences of 415 students toward six pocket parks photographs. Multiple regression analysis was used to predict the relationship between students' social interaction and preferred pocket parks. The results indicate that students preferred pockets that provide variety in softscape and activities as well as offer proper hardscape and shade to enhance their social interaction. The results also show that students from different ethnicities, education status and universities have different social interaction levels on Malaysian campus grounds. The current study contributes to integrating nearby pocket parks in outdoor social interaction to improve campus urban design and academic experience. Hence, the study's findings are of great importance for policymakers, architects, landscape architects, urban planners, and researchers in the field in creating sustainable-socially responsive campuses.

Assessing Visual Preferences of the Local Public for Environmental Mitigation Measures of Hydropower Impacts—Does Point-of-View Location Make a Difference?

Hydropower is a highly appreciated climate-friendly source of energy production. However, it has non-negligible negative impacts on the environment and landscape aesthetics where the energy is produced, affecting the recreational interests of the public using the respective local river spaces. The preferences of the local public are increasingly assessed and involved in the planning of mitigation measures for impacted rivers. Aesthetic assessment methods using a common user perspective, i.e., an “on-the-ground” perspective, could potentially be improved by using an aerial perspective facilitated by modern drone technology. Studies on the compatibility of these two perspectives of assessment in terms of public preference elicitation are lacking so far. In river Nea, Norway, we conducted a quantitative analysis of the visual preferences of the local public for different environmental mitigation measures related to weirs, minimum flow, and recreational infrastructure using both perspectives. The results indicate that there exist significant differences in the preferences for scenarios based on the two different visual perspectives, and that a compatibility between them cannot be assumed and therefore requires further investigation. Finally, based on our study setup and previous experience, we outline and propose a standardized procedure for the visualization of mitigation measures as an input to environmental design projects where public perception is incorporated.

The mechanisms of social evaluation in infancy: A preregistered exploration of infants' eye-movement and pupillary responses to prosocial and antisocial events

Past research shows infants selectively touch and look longer at characters who help versus hinder others (Hamlin et al., 2007; 2010); however, the mechanisms underlying this tendency remain under-specified. The current preregistered experiment approaches this question by examining infants’ real-time looking behaviors during prosocial and antisocial events, and exploring how individual infants’ looking behaviors correlate with helper preferences. Using eye-tracking, 34 five-month-olds were familiarized with two blocks of the “hill” scenario originally developed by Kuhlmeier et al., (2003), in which a climber tries unsuccessfully to reach the top of a hill and is alternately helped or hindered. Infants’ visual preferences were assessed after each block of 6 helping and hindering events by proportional looking time to the helper versus hinderer in an image of the characters side-by-side. Results showed that, at the group level, infants looked longer at the helper after viewing 12 (but not after viewing 6) helping and hindering videos. Moreover, individual infants’ average preference for the helper was predicted by their looking behaviors, particularly those suggestive of an understanding of the climber’s unfulfilled goal. These results shed light on how infants process helping/hindering scenarios, and suggest that goal understanding is important for infants’ helper preferences.

“May I Grab Your Attention?”: An Investigation Into Infants' Visual Preferences for Handled Objects Using Lookit as an Online Platform for Data Collection

We examined the relation between 4- to 12-month-old infants' (N = 107) motor development and visual preference for handled or non-handled objects, using Lookit (lookit.mit.edu) as an online tool for data collection. Infants viewed eight pairs of objects, and their looking was recorded using their own webcam. Each pair contained one item with an easily graspable “handle-like” region and one without. Infants' duration of looking at each item was coded from the recordings, allowing us to evaluate their preference for the handled item. In addition, parents reported on their infants' motor behavior in the previous week. Overall, infants looked longer to handled items than non-handled items. Additionally, by examining the duration of infants' individual looks, we show that differences in infants' interest in the handled items varied both by infants' motor level and across the course of the 8-s trials. These findings confirm infant visual preferences can be successfully measured using Lookit and that motor development is related to infants' visual preferences for items with a graspable, handle-like region. The relative roles of age and motor development are discussed.

Abnormal visual attention to simple social stimuli in 4-month-old infants at high risk for Autism

Despite an increasing interest in detecting early signs of Autism Spectrum Disorders (ASD), the pathogenesis of the social impairments characterizing ASD is still largely unknown. Atypical visual attention to social stimuli is a potential early marker of the social and communicative deficits of ASD. Some authors hypothesized that such impairments are present from birth, leading to a decline in the subsequent typical functioning of the learning-mechanisms. Others suggested that these early deficits emerge during the transition from subcortically to cortically mediated mechanisms, happening around 2–3 months of age. The present study aimed to provide additional evidence on the origin of the early visual attention disturbance that seems to characterize infants at high risk (HR) for ASD. Four visual preference tasks were used to investigate social attention in 4-month-old HR, compared to low-risk (LR) infants of the same age. Visual attention differences between HR and LR infants emerged only for stimuli depicting a direct eye-gaze, compared to an adverted eye-gaze. Specifically, HR infants showed a significant visual preference for the direct eye-gaze stimulus compared to LR infants, which may indicate a delayed development of the visual preferences normally observed at birth in typically developing infants. No other differences were found between groups. Results are discussed in the light of the hypotheses on the origins of early social visual attention impairments in infants at risk for ASD.

ERRATUM: THE ROLE OF VISUAL PREFERENCES IN ARCHITECTURE VIEWS

The article “The role of visual preferences in architecture views” by Ali Akbar Amini, Bahman Adibzadeh, published on 24 September 2020 in the Journal of Architecture and Urbanism, 44(2), 122–127, https://doi.org/10.3846/jau.2020.12582 contained a following errors on: 122 p. The source is incorrectly cited in the text. The correct citation is: (de la Fuente Suárez, 2016) 126 p. The references incorrectly indicate author name, lastname and title of article. The correct citation is: de la Fuente Suárez, L. A. (2016). Towards experiential representation in architecture. Journal of Architecture and Urbanism, 40(1), 47–58. https://doi.org/10.3846/20297955.2016.1163243 Corrected version of the article is available online. The publisher apologises for this error.

Changes in the Soundscape of the Public Space Close to a Highway by a Noise Control Intervention

The deployment of measures to mitigate sound during propagation outdoors is most often a compromise between the acoustic design, practical limitations, and visual preferences regarding the landscape. The current study of a raised berm next to a highway shows a number of common issues like the impact of the limited length of the noise shielding device, initially non-dominant sounds becoming noticeable, local drops in efficiency when the barrier is not fully continuous, and overall limited abatement efficiencies. Detailed assessments of both the objective and subjective effect of the intervention, both before and after the intervention was deployed, using the same methodology, showed that especially the more noise sensitive persons benefit from the noise abatement. Reducing the highest exposure levels did not result anymore in a different perception compared to more noise insensitive persons. People do react to spatial variation in exposure and abatement efficiency. Although level reductions might not be excessive in many real-life complex multi-source situations, they do improve the perception of the acoustic environment in the public space.