When people estimate the summative carbon footprint of a sequence of events, how are the individual events integrated? In three experiments, we found that summative carbon footprint judgments of item sequences are disproportionately influenced by items at the end of the sequence in comparison with those at the beginning—a recency effect. When, for example, sequences ended with a low carbon footprint item, they were assigned a lower carbon footprint than corresponding sequences with an identical content but different item order. The results also revealed that a green peak (presenting many low carbon footprint items at once) had a relatively large effect on estimates when the peak was contextually distinct from other items in terms of its valence. The results are consistent with an account within which distinctiveness of representations within short-term memory differentially influences decision-making and suggest that memory processes bias the perceived environmental footprint of temporally separated instances.

When asked to estimate the carbon footprint of a bundle of low carbon footprint and high carbon footprint items, people typically report a lower value compared to estimating the high carbon footprint items alone. This finding is called the negative footprint illusion. Previous research suggests that people might be made less susceptible to this effect depending on whether they are asked to evaluate how environmentally friendly or how environmentally damaging the items are. In the current study, we used large instead of small stimulus sets (i.e. a more powerful experimental manipulation than that in previous research) and show under these circumstances it does not matter whether participants are required to make friendliness or damaging estimates. The role of attribute substitution along with other conceptual and methodological issues to the negative footprint illusion are discussed, particularly in relation to a recent paper by Gorissen et al. [2024. Green versus grey framing: Exploring the mechanism behind the negative footprint illusion in environmental sustainability assessments. Sustainability, 16(4), 1411]. 

What causes interference in short-term memory? We report the novel finding that immediate memory for visually-presented verbal items is sensitive to disruption from task-irrelevant vibrotactile stimuli. Specifically, short-term memory for a visual sequence is disrupted by a concurrently presented sequence of vibrations, but only when the vibrotactile sequence entails change (when the sequence “jumps” between the two hands). The impact on visual-verbal serial recall was similar in magnitude to that for auditory stimuli (Experiment 1). Performance of the missing item task, requiring recall of item-identity rather than item-order, was unaffected by changing-state vibrotactile stimuli (Experiment 2), as with changing-state auditory stimuli. Moreover, the predictability of the changing-state sequence did not modulate the magnitude of the effect, arguing against an attention-capture conceptualisation (Experiment 3). Results support the view that interference in short-term memory is produced by conflict between incompatible, amodal serial-ordering processes (interference-by-process) rather than interference between similar representational codes (interference-by-content).

The addition of environmentally friendly items to conventional items sometimes leads people to believe that the carbon footprint of the entire set decreases rather than increases. This negative footprint illusion is supposedly underpinned by an averaging bias: people base environmental impact estimates not on the total impact of items but on their average. Here, we found that the illusion’s magnitude increased with the addition of a greater number of “green” items when the number of conventional items remained constant (Studies 1 and 2), supporting the averaging-bias account. We challenged this account by testing what happens when the number of items in the conventional and “green” categories vary while holding the ratio between the two categories constant (Study 3). At odds with the averaging-bias account, the magnitude of the illusion increased as the category size increased, revealing a category-size bias, and raising questions about the interplay between these biases in the illusion.

As a climate change mitigation strategy, environmentally certified 'green' buildings with low carbon footprints are becoming more prevalent in the world. An interesting psychological question is how people perceive the carbon footprint of these buildings given their spatial distributions in a given community. Here we examine whether regular distribution (i.e., buildings organized in a block) or irregular distribution (i.e., buildings randomly distributed) influences people's perception of the carbon footprint of the communities. We first replicated the negative footprint illusion, the tendency to estimate a lower carbon footprint of a combined group of environmentally certified green buildings and ordinary conventional buildings, than the carbon footprint of the conventional buildings alone. Importantly, we found that irregular distribution of the buildings increased the magnitude of the negative footprint illusion. Potential applied implications for urban planning of green buildings are discussed.

Irrelevant sounds can be very distracting, especially when trying to recall information according to its serial order. The irrelevant sound effect (ISE) has been studied in the literature for more than 40 years, yet many questions remain. One goal that has received little attention involves the discernment of a predictive factor, or individual difference characteristic, that would help to determine the size of the ISE. The current experiments were designed to replicate and extend prior work by Macken, Phelps, and Jones (Psychonomic Bulletin & Review, 16, 139-144, 2009), who demonstrated a significant predictive relationship between the size of the ISE and a type of auditory processing called global pattern matching. The authors also found a relationship between auditory processing involving deliberate recoding of sounds and serial order recall performance in silence. Across two experiments, this dissociation was not replicated. Additionally, the two types of auditory processing were not significantly correlated with each other. The lack of a clear pattern of findings replicating the Macken et al. (Psychonomic Bulletin & Review, 16, 139-144, 2009) study raises several questions regarding the need for future research on the characteristics of these auditory processing tasks, and the stability of the measurement of the ISE itself.

Classically, attentional selectivity has been conceptualized as a passive by-product of capacity-limits on stimulus-processing. Here, we examine the role of more active cognitive control processes in attentional selectivity, focusing on how distraction from task-irrelevant sound is modulated by levels of task-engagement in a visually-presented short-term memory task. Task-engagement was varied by manipulating the load involved in the encoding of the (visually-presented) to-be-remembered items. Using a list of Navon letters (where a large letter is composed of smaller, different-identity, letters), participants were oriented to attend and serially recall the list of large letters (low encoding-load) or to attend and serially recall the list of small letters (high encoding-load). Attentional capture by a single deviant noise burst within a task-irrelevant tone sequence (the deviation effect) was eliminated under high encoding-load (Experiment 1). However, distraction from a continuously changing sequence of tones (the changing-state effect) was immune to the influence of load (Experiment 2). This dissociation in the amenability of the deviation effect and the changing-state effect to cognitive control supports a duplex- over a unitary-mechanism account of auditory distraction in which the deviation effect is due to attentional capture while the changing-state effect reflects direct interference between the processing of the sound and processes involved in the focal task. That the changing-state effect survives high encoding-load also goes against an alternative explanation of the attenuation of the deviation effect under high load in terms of the depletion of a limited perceptual resource that would result in diminished auditory processing.

Task-irrelevant background sound can disrupt performance of visually based cognitive tasks. The cross-modal breakdown of attentional selectivity in the context of reading was addressed using analyses of eye movements. Moreover, the study addressed whether task-sensitivity to distraction via background speech on reading was modulated by the cognitive demands of the focal task. Two randomly-assigned groups of native Chinese participants read the same set of Chinese experimental sentences while being exposed to meaningful speech, meaningless (foreign) speech, or silence. For one group, participants were instructed to judge whether the sentences made sense (i.e., semantic acceptability task); for another, participants were instructed to detect whether the sentences contained a noncharacter (i.e., noncharacter detection task). Results showed no significant effect across sound conditions for the noncharacter detection task. For the semantic acceptability task, however, there was a substantial disruptive effect of the meaningfulness of the speech. Compared with reading with meaningless speech or reading in silence, the meaningful speech increased numbers of fixations, regressions, regression path, and total reading times. These results suggest that the disruption of reading by background speech is jointly dependent on the nature of the speech and the task process deployed, thereby favoring an Interference-by-Process account over Interference-by-Content and Attentional Diversion accounts of distraction to reading by background sound.

Automatic information processing has been and still is a debated topic. Traditionally, automatic processes are deemed to take place autonomously and independently of top-down cognitive control. For decades, the literature on reading has brought to the fore empirical phenomena such as Stroop and semantic priming effects that provide support for the assumption that semantic information can be accessed automatically. More recently, there has been growing evidence that semantic processing is in fact susceptible to higher-level cognitive influences, suggesting that this form of processing is instead conditionally automatic. The purpose of the present study was to revisit this debate using a novel approach: The automatic access to the meaning of irrelevant auditory stimuli was tested through the assessment of their distractive power. More specifically, we aimed to examine whether a categorical change in the content of to-be-ignored auditory sequences composed of speech items that are personally nonsignificant to participants (e.g.. a digit among letters) can disrupt an unrelated visual focal task. In seven experiments. we assessed this categorical deviation effect and its functional properties. We established that distraction by categorical deviation is noncontingent on the activated task set and appears resistant to top-down control manipulations. By suggesting not only that the semantic content of the irrelevant sound can be extracted preattentively, but also that such semantic activation is ineluctable during auditory distraction, these findings shed new light on the automatic nature of semantic processing.