Individual Differences Approach Research Articles

EXPRESS: Alexithymia does not explain facial expression recognition difficulties across the dark triad spectrum.

Using an individual differences approach (N=236) we assessed whether trait alexithymia was able to predict unique variance in facial expression discrimination ability and facial expression labelling ability above and beyond an individual's level of dark triad traits. Alexithymia has been shown to be associated with the Dark Triad, and recent evidence has suggested that co-occurring alexithymia may explain facial expression recognition difficulties in autism spectrum disorder. Here we tested this alexithymia hypothesis for individuals on the dark triad spectrum. Results showed that autistic traits, alexithymic traits and dark triad traits all correlated with expression recognition ability. However, linear regression models showed that an individual's level of dark triad traits, their level of autistic traits, and a brief measure of general cognitive ability each predicted unique variance in facial expression discrimination and facial expression labelling ability, but an individual's level of alexithymic traits predicted no additional unique variance. We suggest that Dark Triad and Autistic traits each uniquely contribute to expression recognition ability alongside general cognitive ability.

A common factor underlying individual differences in confirmation bias

When they are asked to test a given hypothesis, individuals tend to be biased towards confirming evidence. This phenomenon has been documented on different cognitive components: information search, weighing of evidence, and memory recall. However, the interpretation of these observations has been debated, and it remains unclear whether they truly reflect a confirmation bias (as opposed to e.g., a bias towards positive information). In the present study we aimed at evaluating whether these biases might be subtended by a common factor. We adapted three classic experimental paradigms on hypothesis testing (Wason selection task, 2-4-6 task, and interviewee task) and examined the relation between these biases using an individual differences approach. Participants (N = 200) completed a total of nine behavioral tasks, in which each component of confirmation bias was measured in each of the three experimental paradigms. Correlations and factor analyses within a multitrait–multimethod framework indicated greater convergence of bias scores within each component across paradigms, than within experimental paradigms. This suggests that a common factor underlies the different measurements of confirmation bias across experimental paradigms, at least to some extent. In these paradigms, thus, biases towards confirming evidence may truly reflect a confirmation bias.

Lexical interference and prediction in sentence processing among Russian heritage speakers: an individual differences approach

In line with emerging trends examining sentence processing in heritage language (HL) bilingualism and adopting an individual differences approach, the present study investigated the role of prediction and lexical interference in 68 Russian HL bilinguals in North America. The former was investigated by examining how Russian HL bilinguals processed sentences with semantically constraining verbs, whereas the latter was assessed examining how contextually globally irrelevant but locally coherent color word information is processed. The findings revealed that, as a group, participants demonstrated predictive processing and were subject to lexical interference. To understand inter-participant variation, we examined the roles prediction and/or interference play as a function of individual differences in cognitive control (as measured by a Flanker task), performance on vocabulary and gender knowledge tasks as well as participants’ individual language history and use (LHQ3, Li et al., Biling Lang Cogn 23:938–944, 2020). Indeed, these analyses revealed that individual language knowledge and domain-general cognitive control play crucial roles in how prediction and/or interference play out in HL processing.

Schooling and language usage matter in heritage bilingual processing: Sortal classifiers in Mandarin

Mandarin sortal classifiers simultaneously encode semantic and grammatical form class cues. Building on a second language (L2) study of Grüter et al. we used the same visual world eye-tracking experiment, designed to examine the relative use of the two cues, testing Mandarin heritage speakers (HSs) living in an English-speaking environment. Given the importance of understanding individual differences, the present study also examined if/how individual HSs may systematically differ as a function of experience with Mandarin. As a group, HSs – like the first language (L1) group in Grüter et al.’s study – showed a clear reliance on the grammatical form class cue. Nevertheless, individual HSs with Mandarin schooling and with more Mandarin social exposure/use showed more reliance on semantics, the L2 pattern observed in Grüter et al. We discuss why this latter pattern might have obtained (formal and informal literacy), while highlighting the value of individual difference approaches to understanding HS processing.

On the lasting impact of mild traumatic brain injury on working memory: Behavioural and electrophysiological evidence

Despite increasing recognition of the significance of mild traumatic brain injury (mTBI), the long-term cognitive consequences of the injury remain unclear. More sensitive measures that can detect subtle cognitive changes and consideration of individual variability are needed to properly characterise cognitive outcomes following mTBI. Here, we used complex behavioural tasks, individual differences approaches, and electrophysiology to investigate the long-term cognitive effects of a history of mTBI. In Experiment 1, participants with self-reported mTBI history (n=82) showed poorer verbal working memory performance on the operation span task compared to control participants (n=88), but there were no group differences in visual working memory, multitasking, cognitive flexibility, attentional control, visuospatial ability, or information processing speed. Individual differences analyses revealed that time since injury and presence of memory loss predicted visual working memory capacity and visuospatial ability, respectively, in those with mTBI history. In Experiment 2, participants with mTBI history (n=20) again demonstrated poorer verbal working memory on the operation span task compared to control participants (n=38), but no group differences were revealed on a visuospatial complex span task or simpler visual working memory measures. We also explored the electrophysiological indices of visual working memory using EEG during a change detection task. No differences were observed in early sensory event-related potentials (P1, N1) or the later negative slow wave associated with visual working memory capacity. Together, these findings suggest that mTBI history may be associated with a lasting, isolated disruption in the subsystem underlying verbal working memory storage. The results emphasise the importance of sensitive cognitive measures and accounting for individual variability in injury characteristics when assessing mTBI outcomes.

The role of sound-to-symbol literacy in phonological awareness: Evidence from Cantonese

Phonological awareness reflects linguistic knowledge related to the sound system of a language. Individual development of phonological awareness is known to progress from larger to smaller sized units and is promoted by the acquisition of literacy, especially in alphabet-based writing systems that are built around sound-to-symbol correspondences. The present study addressed the nature of phonological awareness in speakers of a logographically scripted language. It investigated phonological awareness in adult speakers of Cantonese hailing from Hong Kong who (compared to speakers of other logographically scripted languages) traditionally received little sound-based assistance from tools like Pinyin or Zhu-yin-Fu-Hao when they acquired orthography. The study adopted an individual difference approach, quantifying individually variable levels of experience with a sound-to-symbol writing system and their relationship to phonological awareness. Fifty-seven Hong-Kong speakers of Cantonese took part online, completing rhyme judgment and phoneme monitoring tasks, alongside an extensive background questionnaire. The main prediction that Cantonese speakers who had a relatively high level of experience with sound-to-symbol writing would show an advantage in phonological awareness at the subsyllabic level was largely borne out by the data. The findings of the present study suggest that phonological awareness is a complex set of dissociable skills, shaped by the linguistic and orthographic experience of individual speakers.

The (lack of) correlation between evoked and spontaneous brain oscillations: an individual difference approach

The (lack of) correlation between evoked and spontaneous brain oscillations: an individual difference approach

Associations among attentional state, retrieval quality, and mnemonic discrimination

Memory specificity is shown when participants reject lures that are similar to studied objects. Lure rejections may reflect hippocampal pattern separation that encodes objects distinctively. However, lure features shared with studied objects may evoke pattern completion of varying quality. This was shown when self-reported attention during study promoted lure rejections and false alarms. We used an experimental and individual differences approach to examine the roles of attentive encoding and retrieval quality in lure classifications. An object-based mnemonic discrimination task included thought probes during study and subjective retrieval reports after recognition responses. On-task reports reflecting attentive encoding were associated with lure rejections and false alarms within-and between-subjects. Additionally, accurate lure and target classifications were more strongly associated with subjective recollection following on- than off-task reports. Collectively, these results suggest that attention during study was associated with recollection of criterial features that differentiated existing memories from perceptual inputs.

Individual differences in spatial working memory strategies differentially reflected in the engagement of control and default brain networks.

Spatial locations can be encoded and maintained in working memory using different representations and strategies. Fine-grained representations provide detailed stimulus information, but are cognitively demanding and prone to inexactness. The uncertainty in fine-grained representations can be compensated by the use of coarse, but robust categorical representations. In this study, we employed an individual differences approach to identify brain activity correlates of the use of fine-grained and categorical representations in spatial working memory. We combined data from six functional magnetic resonance imaging studies, resulting in a sample of $155$ ($77$ women, $25 \pm 5$ years) healthy participants performing a spatial working memory task. Our results showed that individual differences in the use of spatial representations in working memory were associated with distinct patterns of brain activity. Higher precision of fine-grained representations was related to greater engagement of attentional and control brain systems throughout the task trial, and the stronger deactivation of the default network at the time of stimulus encoding. In contrast, the use of categorical representations was associated with lower default network activity during encoding and higher frontoparietal network activation during maintenance. These results may indicate a greater need for attentional resources and protection against interference for fine-grained compared with categorical representations.

Individual differences in spatial working memory strategies differentially reflected in the engagement of control and default brain networks.

Spatial locations can be encoded and maintained in working memory using different representations and strategies. Fine-grained representations provide detailed stimulus information, but are cognitively demanding and prone to inexactness. The uncertainty in fine-grained representations can be compensated by the use of coarse, but robust categorical representations. In this study, we employed an individual differences approach to identify brain activity correlates of the use of fine-grained and categorical representations in spatial working memory. We combined data from six fMRI studies, resulting in a sample of 155 (77 women, 25 ± 5 years) healthy participants performing a spatial working memory task. Our results showed that individual differences in the use of spatial representations in working memory were associated with distinct patterns of brain activity. Higher precision of fine-grained representations was related to greater engagement of attentional and control brain systems throughout the task trial, and the stronger deactivation of the default network at the time of stimulus encoding. In contrast, the use of categorical representations was associated with lower default network activity during encoding and higher frontoparietal network activation during maintenance. These results may indicate a greater need for attentional resources and protection against interference for fine-grained compared to categorical representations.

The role of working memory capacity in the temporal compression of episodic memories: An individual differences approach.

Remembering past events usually takes less time than their actual duration-their unfolding is temporally compressed in episodic memory. The rate of temporal compression (i.e., the ratio of the actual duration of an event to the duration of its remembering) is not constant but varies between individuals and as a function of the structure of events (e.g., how they can be divided into shorter subevents). However, the cognitive mechanisms underlying these variations remain poorly understood. Given its role in the encoding and retrieval of information in episodic memory, working memory (WM) capacity could be an important determinant of temporal compression rates. We tested this hypothesis in two experiments in which we asked participants to watch and then mentally replay short videos showing people engaged in daily life activities. We showed that temporal compression rates depend on an interplay between WM and the structure of the remembered events: participants' WM capacity (assessed using complex span tasks) was negatively associated with temporal compression rates, but only when the remembered events contained few event boundaries (i.e., few subevents). This suggests that the temporal compression of events in episodic memory emerges when some of the subevents to be retained are too long to be fully represented in WM. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Supplemental Material for The Role of Working Memory Capacity in the Temporal Compression of Episodic Memories: An Individual Differences Approach

Supplemental Material for The Role of Working Memory Capacity in the Temporal Compression of Episodic Memories: An Individual Differences Approach

Mapping the landscape of spatial literacy research: Bibliometric analysis

The study aims to provide a comprehensive overview of spatial literacy research through a bibliometric analysis, focusing on its development, essential themes, key contributors, and collaboration patterns. Using statistical text-mining and citation link-based clustering techniques, 690 spatial literacy publications from the Scopus database were analyzed, with data extracted on February 18, 2024. The analysis revealed a steady increase in spatial literacy publications, peaking in 2009, and identified key peaks in cited papers in 1996, 2003 and 2012, with a subsequent decline post-2012. Document profiles primarily consisted of articles (60.14%) and sourced from journals (67.97%), with The Journal of Geography being the most active title. Notably, Newcombe, N.S., emerged as the most productive author, while the work of Bednarz and Kemp received the highest number of citations. ‘The Separability of Working Memory Resources for Spatial Thinking and Language Processing: An Individual Differences Approach’ by Shah and Miyake was identified as the most influential document, garnered a minimum of 100 citations per written document. Additionally, the United States stood out with both the largest number of publications and the highest citation impact in spatial literacy research. This bibliometric analysis provides valuable insight into the spatial literacy research landscape, guiding for future research directions and fostering collaborations in this field.

Predictive processing of music and language in autism: Evidence from Mandarin and English speakers.

Atypical predictive processing has been associated with autism across multiple domains, based mainly on artificial antecedents and consequents. As structured sequences where expectations derive from implicit learning of combinatorial principles, language and music provide naturalistic stimuli for investigating predictive processing. In this study, we matched melodic and sentence stimuli in cloze probabilities and examined musical and linguistic prediction in Mandarin- (Experiment 1) and English-speaking (Experiment 2) autistic and non-autistic individuals using both production and perception tasks. In the production tasks, participants listened to unfinished melodies/sentences and then produced the final notes/words to complete these items. In the perception tasks, participants provided expectedness ratings of the completed melodies/sentences based on the most frequent notes/words in the norms. While Experiment 1 showed intact musical prediction but atypical linguistic prediction in autism in the Mandarin sample that demonstrated imbalanced musical training experience and receptive vocabulary skills between groups, the group difference disappeared in a more closely matched sample of English speakers in Experiment 2. These findings suggest the importance of taking an individual differences approach when investigating predictive processing in music and language in autism, as the difficulty in prediction in autism may not be due to generalized problems with prediction in any type of complex sequence processing.

Temporal mechanisms in frontoparallel stereomotion revealed by individual differences analysis.

Masking experiments, using vertical and horizontal sinusoidal depth corrugations, have suggested the existence of more than two spatial-frequency disparity mechanisms. This result was confirmed through an individual differences approach. Here, using factor analytic techniques, we want to investigate the existence of independent temporal mechanisms in frontoparallel stereoscopic (cyclopean) motion. To construct stereomotion, we used sinusoidal depth corrugations obtained with dynamic random-dot stereograms. Thus, no luminance motion was present monocularly. We measured disparity thresholds for drifting vertical (up-down) and horizontal (left-right) sinusoidal corrugations of 0.4 cyc/deg at 0.25, 0.5, 1, 2, 4, 6, and 8Hz. In total, we tested 34 participants. Results showed a small orientation anisotropy with lower thresholds for horizontal corrugations. Disparity thresholds as a function of temporal frequency were almost constant from 0.25 up to 1Hz, and then they increased monotonically. Principal component analysis uncovered two significant factors for vertical and two for horizontal corrugations. Varimax rotation showed that one factor loaded from 0.25 to 1-2Hz and a second factor from 2 to 4 to 8Hz. Direct Oblimin rotation indicated a moderate intercorrelation of both factors. Our results suggest the possible existence of two somewhat interdependent temporal mechanisms involved in frontoparallel stereomotion.

The role of pattern coherence in interocular grouping during binocular rivalry: Insights from individual differences

Interocular grouping during binocular rivalry occurs when two images presented to each eye combine into a coherent pattern. The experience of interocular grouping is thought to be influenced by both eye-of-origin, which involves excitatory lateral connections among monocular neurons, and pattern coherence, which results from top-down intervention from higher visual areas. However, it remains unclear which factor plays a more significant role in the interocularly-grouped percepts during binocular rivalry. The current study employed an individual difference approach to investigate whether grouping dynamics are mainly determined by eye-of-origin or pattern coherence. We found that participants who perceived interocularly-driven coherent percepts for a longer duration also tended to experience longer periods of monocularly-driven coherent percepts. In contrast, participants who experienced non-coherent piecemeal percepts for an extended duration in conventional rivalry also had longer duration of non-coherent percepts in the interocular coherence setting. This individual differences in experiencing interocular grouping suggest that pattern coherence exerts a stronger influence on grouping dynamics during binocular rivalry compared to eye-of-origin factors.

Indistinguishable behavioural and neural correlates of perceptual self-other distinction in autistic and neurotypical adults

Previous research has suggested that self-bias (i.e., enhanced cognitive processing of self-versus other-relevant information) may be atypical in autism spectrum conditions (ASC), perhaps due to difficulties with self-other distinction. However, empirical evidence for this is inconsistent, and the neural basis of processing differences remains unknown. We present two experiments that aimed to test perceptual self-bias and familiarity effects in ASC using a perceptual-association task. Participants were asked to distinguish face/label associations of the self from those of other people of differing levels of familiarity (i.e., friend vs stranger). Experiment 1 took an individual differences approach by testing whether behavioural self-bias is associated with the number of autistic traits in a neurotypical adult sample (N = 59). Experiment 2 took a case–control approach by testing whether behavioural self-bias and associated ERP responses differ between neurotypical (N = 27) and autistic (N = 30) adults. Across both experiments, behavioural results showed that participants experienced a self-bias (self > friend and stranger) and a familiarity effect (e.g., friend > stranger); neither effect was affected by the number of autistic traits or autism diagnosis. In Experiment 2, analysis of N1, N2, and P3 ERP components revealed a typical self-bias in both groups (self distinct from friend and stranger), and only the autistic group showed evidence of a familiarity effect (N2 more negative-going for stranger than friend). The findings are discussed in relation to self-other distinction ability, and the relevance of other neuropsychological and psychiatric conditions such as anxiety and alexithymia are also considered.

Self-esteem mediates the relationship between the parahippocampal gyrus and decisional procrastination at resting state.

When faced with a conflict or dilemma, we tend to postpone or even avoid making a decision. This phenomenon is known as decisional procrastination. Here, we investigated the neural correlates of this phenomenon, in particular the parahippocampal gyrus (PHG) that has previously been identified in procrastination studies. In this study, we applied an individual difference approach to evaluate participants' spontaneous neural activity in the PHG and their decisional procrastination levels, assessed outside the fMRI scanner. We discovered that the fractional amplitude of low-frequency fluctuations (fALFF) in the caudal PHG (cPHG) could predict participants' level of decisional procrastination, as measured by the avoidant decision-making style. Importantly, participants' self-esteem mediated the relationship between the cPHG and decisional procrastination, suggesting that individuals with higher levels of spontaneous activity in the cPHG are likely to have higher levels of self-esteem and thus be more likely to make decisions on time. In short, our study broadens the PHG's known role in procrastination by demonstrating its link with decisional procrastination and the mediating influence of self-esteem, underscoring the need for further exploration of this mediation mechanism.

Associations between autobiographical memory and dreaming: An individual-differences approach.

Associations between autobiographical memory and dreaming: An individual-differences approach.

Some young adults hyper-bind too: Attentional control relates to individual differences in hyper-binding.

Hyper-binding - the erroneous encoding of target and distractor information into associative pairs in memory - has been described as a unique age effect caused by declines in attentional control. Previous work has found that, on average, young adults do not hyper-bind. However, if hyper-binding is caused by reduced attentional control, then young adults with poor attention regulation should also show evidence of hyper-binding. We tested this question with an individual differences approach, using a battery of attentional control tasks and relating this to individual differences in hyper-binding. Participants (N = 121) completed an implicit associative memory test measuring memory for both target-distractor (i.e., hyper-binding) and target-target pairs, followed by a series of tasks measuring attentional control. Our results show that on average, young adults do not hyper-bind, but as predicted, those with poor attentional control show a larger hyper-binding effect than those with good attentional control. Exploratory analyses also suggest that individual differences in attentional control relate to susceptibility to interference at retrieval. These results support the hypothesis that hyper-binding in older adults is due to age-related declines in attentional control, and demonstrate that hyper-binding may be an issue for any individual with poor attentional control, regardless of age.