Cognitive Processing Load Research Articles

Spatial release from masking and pupillometry

Speech perception in complex listening environments is driven by both the auditory factors and the cognitive abilities. There are various ways in which cognitive processing while perceiving speech could be measured. In the present study, we applied pupillometry to assess cognitive processing load resulting due to various demands imposed by the presented speech. PupilCore eye glasses were used to capture pupil dilation while doing two tasks: 1. Speech recognition task when the target and the maskers were either colocated or spatially separated, and 2. a localization task where the listeners had to discriminate whether the two sounds originated form the same location or different locations. Initial data analysis revealed different patterns of pupil dilations for the collocated and spatially separated conditions. For the collocated condition, the listeneing effort had a u-shaped pattern as the target-to-masker increased whereas the listening effort linearly increased as the target-to-masker ration increased for the spatially separated condition. Also, the pupil dilation decreased as the localization task became easier. The intricate relationship between listening effort and listening environment will be discussed in detail.

Cognition and Consciousness Entwined.

We argue that cognition (information processing) and internal phenomenological sensations, including emotions, are intimately related and are not separable. We aver that phenomenological sensations are dynamical "modes" of firing behaviour that (i) exist over time and over large parts of the cortex's neuron-to-neuron network and (ii) are consequences of the network-of-networks architecture, coupling the individual neuronal dynamics and the necessary time delay incurred by neuron-to-neuron transmission: if you possess those system properties, then you will have the dynamical modes and, thus, the phenomenological sensations. These modes are consequences of incoming external stimuli and are competitive within the system, suppressing and locking-out one another. On the other hand, the presence of any such mode acts as a preconditioner for the immediate (dynamic) cognitive processing of information. Thus, internal phenomenological sensations, including emotions, reduce the immediate decision set (of feasible interpretations) and hence the cognitive load. For organisms with such a mental inner life, there would clearly be a large cognitive evolutionary advantage, resulting in the well-known "thinking fast, thinking slow" phenomena. We call this the entwinement hypothesis: how latent conscious phenomena arise from the dynamics of the cognitive processing load, and how these precondition the cognitive tasks immediately following. We discuss how internal dynamical modes, which are candidates for emotions down to single qualia, can be observed by reverse engineering large sets of simulations of system's stimulated responses, either using vast supercomputers (with full 10B neuronal network analyses) or else using laptops to do the same for appropriately generalised Kuramoto models (networks of k-dimensional clocks, each representing the 10,000 neurons within a single neural column). We explain why such simplifications are appropriate. We also discuss the consequent cognitive advantages for information-processing systems exhibiting internal sensations and the exciting implications for next-generation (non-binary) computation and for AI.

The cognitive demands of adverse listening conditions for monolingual and bilingual listeners: A pupillometry study

Bilinguals typically underperform relative to monolinguals in speech-perception-in-noise tasks. However, there is little data comparing bilinguals and monolinguals in other types of difficult listening conditions. Furthermore, such differences are typically investigated using off-line intelligibility accuracy scores, which do not necessarily reflect differences in on-line speech processing. In the current study, pupillometry was used during sentence recognition tasks to index cognitive processing load. Monolingual English listeners and English-dominant simultaneous bilingual listeners heard English sentences in four conditions: American-Accented in Quiet, Turkish-Accented in Quiet, American-Accented in Noise, and Face Mask-Attenuated American-Accented in Quiet. Differences in pupil dilation between groups are expected in the latter three conditions. Data collection is on-going, but preliminary results (N = 40) show bilinguals exert more cognitive effort than monolinguals across all conditions.

The restorative effects of short-term exposure to nature in immersive virtual environments (IVEs) as evidenced by participants' brain activities

Short-term exposure to nature has excellent potential to be used as a public health intervention measure. Nevertheless, the physiological and psychological mechanisms of this health benefit are still unclear. In this study, we intend to verify the effects of short-term exposure to nature on psychological functioning and to explore the underlying mechanism through experiments conducted in immersive virtual environments (IVEs). Participants were randomly exposed to videos of an urban forest and an indoor environment in IVEs. Before and after the exposure, a participant's self-perceived stress and cognitive performance were measured using the PSS-14 form and the Stroop task, respectively. Their brain activities during the exposure were measured using the electroencephalogram (EEG). The PSS-14 and the Stroop task results confirmed the benefits of stress reduction and cognitive performance improvements from short-term nature exposure. At the same time, rhythmic brain activities during nature exposure indicated better attentional states. The electrodes around the parietal region detected significantly stronger power spectral density of the theta band than other bands. Also, participants showed high functional connectivity among different brain parts during nature exposure, which revealed better cognitive flexibility. The topographic pattern of the differences in functional connectivity overlapped well with the default mode network (DMN)—a “task-negative” network active during the resting state. The overlap indicated a lower cognitive processing load when exposing to nature. Our results support the hypothesis that nature's restorative effects mainly come from effortless processing in natural environments.

Investigation of the interaction between emotion and working memory load using spatiotemporal pattern similarity analysis

Objective. Accumulating evidence has revealed that emotions can be provided with the modulatory effect on working memory (WM) and WM load is an important factor for the interaction between emotion and WM. However, it remains controversial whether emotions inhibit or facilitate WM and the interaction between cognitive task, processing load and emotional processing remains unclear. Approach. In this study, we used a change detection paradigm wherein memory items have four different load sizes and emotion videos to induce three emotions (negative, neutral, and positive). We performed an event-related spectral perturbation (ERSP) analysis and a spatiotemporal pattern similarity (STPS) analysis on the electroencephalography data. Main results. The ERSP results indicated that alpha and beta oscillations can reflect the difference among WM load sizes and also can reflect the difference among emotions under middle high WM load over posterior brain region in the maintenance stage. Moreover, the STPS results demonstrated a significant interaction between emotion and WM load size in the posterior region and found significantly higher similarity indexes for the negative emotion to the neutral emotion under the middle high WM load during WM maintenance. In addition, The STPS results also revealed that both positive emotion and negative emotion could interfere with the distinction of load sizes. Significance. The consistence of the behavioral, ERSP and STPS results suggested that when the memory load approaches the limit of WM capacity, negative emotion could facilitate WM through the top–down attention modulation promoting the most relevant information storage during WM maintenance.

Pupillometry reveals cognitive demands of lexical competition during spoken word recognition in young and older adults.

In most contemporary activation-competition frameworks for spoken word recognition, candidate words compete against phonological "neighbors" with similar acoustic properties (e.g., "cap" vs. "cat"). Thus, recognizing words with more competitors should come at a greater cognitive cost relative to recognizing words with fewer competitors, due to increased demands for selecting the correct item and inhibiting incorrect candidates. Importantly, these processes should operate even in the absence of differences in accuracy. In the present study, we tested this proposal by examining differences in processing costs associated with neighborhood density for highly intelligible items presented in quiet. A second goal was to examine whether the cognitive demands associated with increased neighborhood density were greater for older adults compared with young adults. Using pupillometry as an index of cognitive processing load, we compared the cognitive demands associated with spoken word recognition for words with many or fewer neighbors, presented in quiet, for young (n = 67) and older (n = 69) adult listeners. Growth curve analysis of the pupil data indicated that older adults showed a greater evoked pupil response for spoken words than did young adults, consistent with increased cognitive load during spoken word recognition. Words from dense neighborhoods were marginally more demanding to process than words from sparse neighborhoods. There was also an interaction between age and neighborhood density, indicating larger effects of density in young adult listeners. These results highlight the importance of assessing both cognitive demands and accuracy when investigating the mechanisms underlying spoken word recognition.

The nature effect in motion: visual exposure to environmental scenes impacts cognitive load and human gait kinematics.

Prolonged exposure to urban environments requires higher cognitive processing resources than exposure to nature environments, even if only visual cues are available. Here, we explored the moment-to-moment impact of environment type on visual cognitive processing load, measuring gait kinematics and reaction times. In Experiment 1, participants (n = 20) walked toward nature and urban images projected in front of them, one image per walk, and rated each image for visual discomfort. Gait speed and step length decreased for exposure to urban as compared with nature scenes in line with gait changes observed during verbal cognitive load tasks. We teased apart factors that might contribute to cognitive load: image statistics and visual discomfort. Gait changes correlated with subjective ratings of visual discomfort and their interaction with the environment but not with low-level image statistics. In Experiment 2, participants (n = 45) performed a classic shape discrimination task with the same environmental scenes serving as task-irrelevant distractors. Shape discrimination was slower when urban scenes were presented, suggesting that it is harder to disengage attention from urban than from nature scenes. This provides converging evidence that increased cognitive demands posed by exposure to urban scenes can be measured with gait kinematics and reaction times even for short exposure times.

Word Frequency Is Associated With Cognitive Effort During Verbal Working Memory: A Functional Near Infrared Spectroscopy (fNIRS) Study.

PurposePsycholinguistic models traditionally view verbal working memory capacity as independent from linguistic features; connectionist models suggest otherwise. Moreover, lexical processing studies show high frequency words differ in cognitive effort from low frequency words, although these effects during concurrent processing of words in working memory are unknown. This novel study examines potential differences in cognitive effort, as measured by differences in HbO2 and Hb, for high frequency versus low frequency words during a working memory paradigm.MethodsA total of 21 neurologically typical participants (age 18–23) completed an auditory, n-back, working memory task comparing performance with high- as compared to low- frequency words. Hemodynamic changes in the prefrontal cortex were recorded with a continuous-wave functional near-infrared spectroscopy (fNIRS) device. Behavioral data (accuracy, reaction time) were recorded using E-prime.ResultsDifferences in word frequency were evident at both behavioral and neurological levels. Participants were more accurate, albeit slower in identifying the target two back in a sequence for low- as compared to high-frequency words. Patterns of hemodynamic changes were also significantly different between HF and LF conditions.ConclusionThe results from this study indicate that the behavioral and neurological signatures inherent in holding high- versus low-frequency words in working memory differs significantly. Specifically, the findings from this study indicated that words differing in frequency place different demands on cognitive processing load in memory updating tasks.

The Index of Cognitive Activity as a Measure of Cognitive Processing Load in Dual Task Settings.

Increases in pupil size have long been used as an indicator of cognitive load. Recently, the Index of Cognitive Activity (ICA), a novel pupillometric measure has received increased attention. The ICA measures the frequency of rapid pupil dilations, and is an interesting complementary measure to overall pupil size because it disentangles the pupil response to cognitive activity from effects of light input. As such, it has been evaluated as a useful measure of processing load in dual task settings coordinating language comprehension and driving. However, the cognitive underpinnings of pupillometry, and any differences between rapid small dilations as measured by the ICA and overall effects on pupil size are still poorly understood. Earlier work has observed that the ICA and overall pupil size may not always behave in the same way, reporting an increase in overall pupil size but decrease in ICA in a dual task setting. To further investigate this, we systematically tested two new dual-task combinations, combining both language comprehension and simulated driving with a memory task. Our findings confirm that more difficult linguistic processing is reflected in a larger ICA. More importantly, however, the dual task settings did not result in an increase in the ICA as compared to the single task, and, consistent with earlier findings, showed a significant decrease with a more difficult secondary task. This contrasts with our findings for pupil size, which showed an increase with greater secondary task difficulty in both tasks. Our results are compatible with the idea that although both pupillometry measures are indicators of cognitive load, they reflect different cognitive and neuronal processes in dual task situations.

A socio-cognitive approach to code-switching: from the perspective of a dynamic usage-based account of language

ABSTRACT This study addresses the social-cognitive interactions that occur in code-switching and integrates social and cognitive factors from a usage-based perspective. It investigates code-switching in two different interaction modes – speech and writing – to consider not only the influence of social factors (social networks and attitudes) but also the relative cognitive processing load. The data were gathered from 40 Chinese-English bilinguals in London, derived from interviews and written data on their most active social media site, SinaWeibo. Their socio-biographical data were collected via a questionnaire. A multivariate analysis shows that, rather than there being a simple dominance of either the social or the cognitive factors, there is an interplay between the two. A speaker’s code-switching corresponds to his/her previous exposure through social networks, but personal attitudes, e.g. a positive view of English, can override network-based predictions of use. Crucially, however, we only see attitudes exerting this significant effect within the domain of contexts with low cognitive processing demand (e.g. asynchronous writing). The findings of this study show that personal preference can indeed override language usage in interactive networks, but such effect is constrained by individual differences in cognitive capacities of processing, which in turn relates back to the frequency of usage which automatizes processing.

Effects of attention on the speech reception threshold and pupil response of people with impaired and normal hearing

For people with hearing difficulties, following a conversation in a noisy environment requires substantial cognitive processing, which is often perceived as effortful. Recent studies with normal hearing (NH) listeners showed that the pupil dilation response, a measure of cognitive processing load, is affected by ‘attention related’ processes. How these processes affect the pupil dilation response for hearing impaired (HI) listeners remains unknown. Therefore, the current study investigated the effect of auditory attention on various pupil response parameters for 15 NH adults (median age 51 yrs.) and 15 adults with mild to moderate sensorineural hearing loss (median age 52 yrs.). Both groups listened to two different sentences presented simultaneously, one to each ear and partially masked by stationary noise. Participants had to repeat either both sentences or only one, for which they had to divide or focus attention, respectively. When repeating one sentence, the target sentence location (left or right) was either randomized or blocked across trials, which in the latter case allowed for a better spatial focus of attention. The speech-to-noise ratio was adjusted to yield about 50% sentences correct for each task and condition. NH participants had lower (‘better’) speech reception thresholds (SRT) than HI participants. The pupil measures showed no between-group effects, with the exception of a shorter peak latency for HI participants, which indicated a shorter processing time. Both groups showed higher SRTs and a larger pupil dilation response when two sentences were processed instead of one. Additionally, SRTs were higher and dilation responses were larger for both groups when the target location was randomized instead of fixed. We conclude that although HI participants could cope with less noise than the NH group, their ability to focus attention on a single talker, thereby improving SRTs and lowering cognitive processing load, was preserved. Shorter peak latencies could indicate that HI listeners adapt their listening strategy by not processing some information, which reduces processing time and thereby listening effort.

Microsaccade-rate indicates absorption by music listening.

The power of music is a literary topos, which can be attributed to intense and personally significant experiences, one of them being the state of absorption. Such phenomenal states are difficult to grasp objectively. We investigated the state of musical absorption by using eye tracking. We utilized a load related definition of state absorption: multimodal resources are committed to create a unified representation of music. Resource allocation was measured indirectly by microsaccade rate, known to indicate cognitive processing load. We showed in Exp. 1 that microsaccade rate also indicates state absorption. Hence, there is cross-modal coupling between an auditory aesthetic experience and fixational eye movements. When removing the fixational stimulus in Exp. 2, saccades are no longer generated upon visual input and the cross-modal coupling disappeared. Results are interpreted in favor of the load hypothesis of microsaccade rate and against the assumption of general slowing by state absorption.

THE IMPACT OF DIFFERENT LOADS OF INVOLVEMENT ON EFL STUDENTS’ INCIDENTAL LEARNING OF IDIOMS

Idioms are essential parts of any language learning that indicate second language proficiency of learners in their communication. However, there is no doubt that idioms are more difficult to learn and comprehend than usual words of phrases. The present study investigated the possible effects of providing different task types with involvement loads on Iranian pre-intermediate EFL students' learning of idiom. A total number of 60 EFL students were selected based on their performance on Quick Placement Test and idiom familiarity test. The participants were randomly divided into three groups each containing 20 students. The data gathered through conducting pretest, posttest, and delayed posttest of L2 idioms were analyzed through descriptive statistics and inferential statistics of one way ANOVA and paired samples t test. The findings revealed that tasks with higher involvement load led to better performance of students both in initial learning and the retention of idioms. The findings would hopefully encourage teachers and learners to use tasks and with deeper cognitive processing and higher involvement load to have more effective learning of English idioms.

The Spatial Release of Cognitive Load in Cocktail Party Is Determined by the Relative Levels of the Talkers.

In a multi-talker situation, spatial separation between talkers reduces cognitive processing load: this is the "spatial release of cognitive load". The present study investigated the role played by the relative levels of the talkers on this spatial release of cognitive load. During the experiment, participants had to report the speech emitted by a target talker in the presence of a concurrent masker talker. The spatial separation (0° and 120° angular distance in azimuth) and the relative levels of the talkers (adverse, intermediate, and favorable target-to-masker ratio) were manipulated. The cognitive load was assessed with a prefrontal functional near-infrared spectroscopy. Data from 14 young normal-hearing listeners revealed that the target-to-masker ratio had a direct impact on the spatial release of cognitive load. Spatial separation significantly reduced the prefrontal activity only for the intermediate target-to-masker ratio and had no effect on prefrontal activity for the favorable and the adverse target-to-masker ratios. Therefore, the relative levels of the talkers might be a key point to determine the spatial release of cognitive load and more specifically the prefrontal activity induced by spatial cues in multi-talker situations.

Opposing effects of perceptual versus working memory load on emotional distraction

Throughout our day-to-day activities, we are subjected to numerous stimuli that compete for our attention; consequently, we must prioritize stimuli for further processing and influence over behaviour. Previous research has demonstrated that the extent to which task-irrelevant distractors are processed is mediated by the nature of the cognitive task, and the level of processing load. Importantly though, the interaction between cognitive task, processing load, and emotional distractor processing remains unclear. This is a particularly important question given the unique ways that emotion interacts with attention, and the fact that some other forms of processing load have been shown to reduce emotional distractor encoding. In the present study, participants were presented with emotional distractors during a perceptual and working memory task, under varying levels of load. In Experiment 1, we showed that the impact of emotional distractors on behaviour was reduced under conditions of high relative to low perceptual load. However, in sharp contrast, high working memory load was associated with increased emotional distraction. Importantly, these results were replicated in Experiment 2. Overall, the impact of processing load on emotional distraction varies according to the cognitive function being performed. These results raise the intriguing possibility that working memory operations deplete some of the cognitive resources needed to control the impact of emotion on behaviour. The findings, therefore, may have important implications for clinical populations featuring cognitive dysfunction and emotional dysregulation.

Cortical Responses and Shape Complexity of Stereoscopic Image - A Simultaneous EEG/MEG Study

Background/Aims: In exploring human factors, stereoscopic 3D images have been used to investigate the neural responses associated with excessive depth, texture complexity, and other factors. However, the cortical oscillation associated with the complexity of stereoscopic images has been studied rarely. Here, we demonstrated that the oscillatory responses to three differently shaped 3D images (circle, star, and bat) increase as the complexity of the image increases. Methods: We recorded simultaneous EEG/MEG for three different stimuli. Spatio-temporal and spatio-spectro-temporal features were investigated by non-parametric permutation test. Results: The results showed that N300 and alpha inhibition increased in the ventral area as the shape complexity of the stereoscopic image increased. Conclusion: It seems that the relative disparity in complex stereoscopic images may increase cognitive processing (N300) and cortical load (alpha inhibition) in the ventral area.

Spatial release of cognitive load measured in a dual-task paradigm in normal-hearing and hearing-impaired listeners.

This study investigated whether spatial separation between talkers helps reduce cognitive processing load, and how hearing impairment interacts with the cognitive load of individuals listening in multi-talker environments. A dual-task paradigm was used in which performance on a secondary task (visual tracking) served as a measure of the cognitive load imposed by a speech recognition task. Visual tracking performance was measured under four conditions in which the target and the interferers were distinguished by (1) gender and spatial location, (2) gender only, (3) spatial location only, and (4) neither gender nor spatial location. Results showed that when gender cues were available, a 15° spatial separation between talkers reduced the cognitive load of listening even though it did not provide further improvement in speech recognition (Experiment I). Compared to normal-hearing listeners, large individual variability in spatial release of cognitive load was observed among hearing-impaired listeners. Cognitive load was lower when talkers were spatially separated by 60° than when talkers were of different genders, even though speech recognition was comparable in these two conditions (Experiment II). These results suggest that a measure of cognitive load might provide valuable insight into the benefit of spatial cues in multi-talker environments.

The pupil response reveals increased listening effort when it is difficult to focus attention

Recent studies have shown that prior knowledge about where, when, and who is going to talk improves speech intelligibility. How related attentional processes affect cognitive processing load has not been investigated yet. In the current study, three experiments investigated how the pupil dilation response is affected by prior knowledge of target speech location, target speech onset, and who is going to talk. A total of 56 young adults with normal hearing participated. They had to reproduce a target sentence presented to one ear while ignoring a distracting sentence simultaneously presented to the other ear. The two sentences were independently masked by fluctuating noise. Target location (left or right ear), speech onset, and talker variability were manipulated in separate experiments by keeping these features either fixed during an entire block or randomized over trials. Pupil responses were recorded during listening and performance was scored after recall. The results showed an improvement in performance when the location of the target speech was fixed instead of randomized. Additionally, location uncertainty increased the pupil dilation response, which suggests that prior knowledge of location reduces cognitive load. Interestingly, the observed pupil responses for each condition were consistent with subjective reports of listening effort. We conclude that communicating in a dynamic environment like a cocktail party (where participants in competing conversations move unpredictably) requires substantial listening effort because of the demands placed on attentional processes.

CE: Original research: hospital system barriers to rapid response team activation: a cognitive work analysis.

The goal of rapid response team (RRT) activation in acute care facilities is to decrease mortality from preventable complications, but such efforts have been only moderately successful. Although recent research has shown decreased mortality when RRTs are activated more often, many hospitals have low activation rates. This has been linked to various hospital, team, and nursing factors. Yet there is a dearth of research examining how hospital systems shape nurses' behavior with regard to RRT activation. Making systemic constraints visible and modifying them may be the key to improving RRT activation rates and saving more lives. The purpose of this study was to use cognitive work analysis to describe factors within the hospital system that shape medical-surgical nurses' RRT activation behavior. Cognitive work analysis offers a framework for the study of complex sociotechnical systems. This framework was used as the organizing element of the study. Qualitative descriptive design was used to obtain data to fill the framework's five domains: resources, tasks, strategies, social systems, and worker competency. Data were obtained from interviews with 12 medical-surgical nurses and document review. Directed content analysis was used to place the obtained data into the framework's predefined domains. Many system factors affected participants' decisions to activate or not activate an RRT. Systemic constraints, especially in cases of subtle or gradual clinical changes, included a lack of adequate information, the availability of multiple strategies, the need to justify RRT activation, a scarcity of human resources, and informal hierarchical norms in the hospital culture. The most profound constraint was the need to justify the call. Justification was based on the objective or subjective nature of clinical changes, whether the nurse expected to be able to "handle" these changes, the presence or absence of a physician, and whether there was an expectation of support from the RRT team. The need for justification led to delays in RRT activation. Although it's generally thought that RRTs are activated without hesitation, this study found the opposite was true. All of the aforementioned constraints increase the cognitive processing load on the nurse. The value of the RRT could be increased by modifying these constraints-in particular, by lifting the need to justify calls, improving protocols, and broadening the range of culturally acceptable triggers-and by involving the RRT earlier in patient cases through discussion, consultation, and collaboration.

The effects of Processing Instruction on the acquisition of English simple past tense: Age and cognitive task demands

AbstractThe present study investigates the effects of Processing Instruction on two different age groups and the role that cognitive task demands might play in the results generated by Processing Instruction. This study includes school-age children and adult native speakers of German learning English as a foreign language – a language combination not previously investigated within the Processing Instruction and individual differences research paradigm. The present study investigates directly whether two different age groups will benefit equally from Processing Instruction in altering their reliance on lexical temporal indicators and redirecting their attention to verb forms on Processing Instruction activities with different cognitive demands. The grammatical feature chosen for this study is the English past simple tense marking tested on both interpretation and production measures. The results from this study provide further evidence that the Processing Instruction is an effective instructional treatment in helping school-age children and adult L2 learners to make accurate form-meaning connections. The results from the first sentence-level interpretation task and the production task showed that Processing Instruction has positive and equal effects on both age groups (school-age learners and adults). The positive effects of instruction were maintained over the delayed post-test for both age groups who made similar gains on the immediate post-test. The results from the second (cognitively more complex) sentence-level interpretation task indicated that the adults made greater gains than school-age learners. However, both groups retained the positive effects of instruction over time. The difference in gains between the two age groups on the second sentence-level interpretation task can be explained in terms of cognitive processing load.