Simultaneous Visual Task Research Articles

Neural tracking of speech acoustics in noise is coupled with lexical predictability as estimated by large language models.

Adults heard recordings of two spatially separated speakers reading newspaper and magazine articles. They were asked to listen to one of them and ignore the other, and EEG was recorded to assess their neural processing. Machine learning extracted neural sources that tracked the target and distractor speakers at three levels: the acoustic envelope of speech (delta- and theta-band modulations), lexical frequency for individual words, and the contextual predictability of individual words estimated by GPT-4 and earlier lexical models. To provide a broader view of speech perception, half of the subjects completed a simultaneous visual task, and the listeners included both native and non-native English speakers. Distinct neural components were extracted for these levels of auditory and lexical processing, demonstrating that native English speakers had greater target-distractor separation compared to non-native English speakers on most measures, and that lexical processing was reduced by the visual task. Moreover, there was a novel interaction of lexical predictability and frequency with auditory processing; acoustic tracking was stronger for lexically harder words, suggesting that people listened harder to the acoustics when needed for lexical selection. This demonstrates that speech perception is not simply a feedforward process from acoustic processing to the lexicon. Rather, the adaptable context-sensitive processing long known to occur at a lexical level has broader consequences for perception, coupling with the acoustic tracking of individual speakers in noise.Significance Statement In challenging listening conditions, people use focused attention to help understand individual talkers and ignore others, which changes their neural processing for speech at auditory through lexical levels. However, lexical processing for natural materials (e.g., conversations, audiobooks) has been difficult to measure, because of limitations of tools to estimate the predictability of individual words in longer discourses. The present investigation uses a contemporary large language model, GPT-4, to estimate word predictability, and demonstrates that listeners make online adaptations to their auditory neural processing in accord with these predictions; neural activity more closely tracks the acoustics of the target talker when words are less predictable from the context.

Assessing Gender Differences in Technical Skills and Confidence in Orthopaedic Surgery Residency Applicants.

Variations in confidence for procedural skills have been demonstrated when comparing male and female medical students in surgical training. This study investigates whether differences in technical skill and self-reported confidence exist between male and female medical students applying to orthopaedic residency. All medical students (2017 to 2020) invited to interview at a single orthopaedic residency program were prospectively evaluated on their technical skills and self-reported confidence. Objective evaluation of technical skill included scores for a suturing task as evaluated by faculty graders. Self-reported confidence in technical skills was assessed before and after completing the assigned task. Scores for male and female students were compared by age, self-identified race/ethnicity, number of publications at the time of application, athletic background, and US Medical Licensing Examination Step 1 score. Two hundred sixteen medical students were interviewed, of which 73% were male (n = 158). No gender differences were observed in suture task technical skill scores or mean difference in simultaneous visual task scores. The mean change from pre-task and post-task self-reported confidence scores was similar between sexes. Although female students trended toward lower post-task self-reported confidence scores compared with male students, this did not achieve statistical significance. Lower self-reported confidence was associated with a higher US Medical Licensing Examination score and with attending a private medical school. No difference in technical skill or confidence was found between male and female applicants to a single orthopaedic surgery residency program. Female applicants trended toward self-reporting lower confidence than male applicants in post-task evaluations. Differences in confidence have been shown previously in surgical trainees, which may suggest that differences in skill and confidence may develop during residency training.

Audiovisual Speech Recognition With a Cochlear Implant and Increased Perceptual and Cognitive Demands.

Speech recognition in complex environments involves focusing on the most relevant speech signal while ignoring distractions. Difficulties can arise due to the incoming signal’s characteristics (e.g., accented pronunciation, background noise, distortion) or the listener’s characteristics (e.g., hearing loss, advancing age, cognitive abilities). Listeners who use cochlear implants (CIs) must overcome these difficulties while listening to an impoverished version of the signals available to listeners with normal hearing (NH). In the real world, listeners often attempt tasks concurrent with, but unrelated to, speech recognition. This study sought to reveal the effects of visual distraction and performing a simultaneous visual task on audiovisual speech recognition. Two groups, those with CIs and those with NH listening to vocoded speech, were presented videos of unaccented and accented talkers with and without visual distractions, and with a secondary task. It was hypothesized that, compared with those with NH, listeners with CIs would be less influenced by visual distraction or a secondary visual task because their prolonged reliance on visual cues to aid auditory perception improves the ability to suppress irrelevant information. Results showed that visual distractions alone did not significantly decrease speech recognition performance for either group, but adding a secondary task did. Speech recognition was significantly poorer for accented compared with unaccented speech, and this difference was greater for CI listeners. These results suggest that speech recognition performance is likely more dependent on incoming signal characteristics than a difference in adaptive strategies for managing distractions between those who listen with and without a CI.

ERPs in an oddball task under vection-inducing visual stimulation.

The neural mechanisms underlying the vection illusion are not fully understood. A few studies have analyzed visually evoked potentials or event-related potentials (ERPs) when participants were exposed to vection-inducing stimulation. However, none of them tested how such stimulation influences the brain activity during performance of the simultaneous visual task. In the present study, ERPs were recorded while subjects (N = 19) performed a discrimination oddball task. Two stimuli (O or X) were presented on the background of central and peripheral visual fields consisting of altered black and white vertical stripes that were stationary or moving horizontally. Three different combinations of these fields were created: (1) both center and periphery stationary (control condition), (2) both center and periphery moving, (3) center stationary and periphery moving. Mean reaction times to targets were shortest in the control condition. The amplitudes of P1 and N2 at occipital locations, and the amplitude of P3 at frontal, central, and parietal locations, were attenuated, and the P3 exhibited longer peak latency when both central and peripheral visual fields were moving. These potentials reflect initial sensory processing and the degree of attention required for processing visual stimuli and performing the task. Our findings suggest that the integration of central and peripheral moving visual fields enhances the vection illusion and slows down reaction times to targets in the oddball task and disrupts the magnitude of electrophysiological responses to targets.

Dividing attention between two simultaneous visual tasks I: The Parvocellular system & the Koniocellular system

Dividing attention between two simultaneous visual tasks I: The Parvocellular system & the Koniocellular system

Dividing attention between two simultaneous visual tasks: The Magnocellular system

Dividing attention between two simultaneous visual tasks: The Magnocellular system

Alterations to locomotor navigation in a complex environment at 7 and 30 days following a concussion in an elite athlete

Primary objective: To compare the locomotor capacity during (1) unobstructed walking and (2) the circumvention of fixed obstacles with and without a simultaneous visual task in an elite athlete before and after a sports-related concussion.Research design: Case report.Methods and procedures: Gait analysis and clinical neuropsychological measures were taken pre- and at 7 and 30 days post-injury in an 18 year old male junior hockey player. The task consisted of walking along an unobstructed or obstructed path with or without a visual interference task. Measurements included dual tasks costs, response errors, maximal gait speed and minimal clearance with the obstacle.Main outcome and results: Although the athlete was symptom-free and neuropsychological test results returned to baseline relatively quickly, he showed continued errors in the interference task, abnormally small obstacle clearance distances and decreased maximal gait speed up to 30 days after the concussion.Conclusions: Concussion can result in persistent planning and attention deficits in ecologically valid, complex environments. This report suggests that functional assessment within an ecological context could be an innovative way to evaluate concussed athletes before sending them back to play, even in the absence of medically related symptoms or abnormal neuropsychological test results.

Part 2: Abstracts of posters

Vallée M, McFadyen BJ, Swaine B, Doyon J, Cantin J-F, Dumas D. Effects of environmental demands on locomotion after traumatic brain injury.To determine the effects of increasingly demanding environments related to simultaneous visual tasks and physical obstructions on the locomotor ability of people with traumatic brain injury (TBI).Group comparison study.Gait analysis laboratory within a postacute rehabilitation facility.Volunteer sample of 9 people (8 men, 1 woman; age, 39.3±13.0y) with moderate to severe TBI and a comparison group of 9 subjects without neurologic problems matched for age and sex (8 men, 1 woman; age, 39.7±12.3y).Not applicable.Reading times for the Stroop bar and Stroop word tasks, walking speeds, stride lengths, and obstacle clearance margin.The TBI group was slower than the control group in performing the Stroop bar task during sitting (P=.002), and while avoiding the narrow obstacle (P=.05), and in performing the Stroop word task while avoiding the wide obstacle (P=.019). Despite their relatively normal gait speeds on level ground, subjects with TBI walked more slowly than control subjects for the narrow (P=.024) and the wide (P=.019) obstacle conditions and for the most complex dual task (P=.042). Greater lead-limb clearance margins were observed for the TBI group than for control subjects for all conditions whereas no differences were found for the trail limb except at the far end of the wide obstacle.Despite their good recovery of locomotor function, with respect to normal level walking speeds and ability to avoid obstacles, subjects with moderate and severe TBI showed residual deficits in relation to greater difficulties in dealing with environments that challenge their locomotor and attentional abilities. The use of such naturally based dual tasks may help identify some of the environmental obstructions to social participation after TBI.

Effects of Environmental Demands on Locomotion After Traumatic Brain Injury

Vallée M, McFadyen BJ, Swaine B, Doyon J, Cantin J-F, Dumas D. Effects of environmental demands on locomotion after traumatic brain injury. Objective To determine the effects of increasingly demanding environments related to simultaneous visual tasks and physical obstructions on the locomotor ability of people with traumatic brain injury (TBI). Design Group comparison study. Setting Gait analysis laboratory within a postacute rehabilitation facility. Participants Volunteer sample of 9 people (8 men, 1 woman; age, 39.3±13.0y) with moderate to severe TBI and a comparison group of 9 subjects without neurologic problems matched for age and sex (8 men, 1 woman; age, 39.7±12.3y). Interventions Not applicable. Main Outcome Measures Reading times for the Stroop bar and Stroop word tasks, walking speeds, stride lengths, and obstacle clearance margin. Results The TBI group was slower than the control group in performing the Stroop bar task during sitting ( P=.002), and while avoiding the narrow obstacle ( P=.05), and in performing the Stroop word task while avoiding the wide obstacle ( P=.019). Despite their relatively normal gait speeds on level ground, subjects with TBI walked more slowly than control subjects for the narrow ( P=.024) and the wide ( P=.019) obstacle conditions and for the most complex dual task ( P=.042). Greater lead-limb clearance margins were observed for the TBI group than for control subjects for all conditions whereas no differences were found for the trail limb except at the far end of the wide obstacle. Conclusions Despite their good recovery of locomotor function, with respect to normal level walking speeds and ability to avoid obstacles, subjects with moderate and severe TBI showed residual deficits in relation to greater difficulties in dealing with environments that challenge their locomotor and attentional abilities. The use of such naturally based dual tasks may help identify some of the environmental obstructions to social participation after TBI.