The over-estimation of distance for self-voice versus other-voice

Self-related stimuli are important cues for people to recognize themselves in the external world and hold a special status in our perceptual system. Self-voice plays an important role in daily social communication and is also a frequent input for self-identification. Although many studies have been conducted on the acoustic features of self-voice, no research has ever examined the spatial aspect, although the spatial perception of voice is important for humans. This study proposes a novel perspective for studying self-voice. We investigated people’s distance perception of their own voice when the voice was heard from an external position. Participants heard their own voice from one of four speakers located either 90 or 180 cm from their sitting position, either immediately after uttering a short vowel (i.e., active session) or hearing the replay of their own pronunciation (i.e., replay session). They were then asked to indicate which speaker they heard the voice from. Their voices were either pitch-shifted by ± 4 semitones (i.e., other-voice condition) or unaltered (i.e., self-voice condition). The results of spatial judgment showed that self-voice from the closer speakers was misattributed to that from the speakers further away at a significantly higher proportion than other-voice. This phenomenon was also observed when the participants remained silent and heard prerecorded voices. Additional structural equation modeling using participants’ schizotypal scores showed that the effect of self-voice on distance perception was significantly associated with the score of delusional thoughts (Peters Delusion Inventory) and distorted body image (Perceptual Aberration Scale) in the active speaking session but not in the replay session. The findings of this study provide important insights for understanding how people process self-related stimuli when there is a small distortion and how this may be linked to the risk of psychosis.

Impact of ventricle size on neuropsychological outcomes in treated pediatric hydrocephalus: an HCRN prospective cohort study

OBJECTIVE In pediatric hydrocephalus, shunts tend to result in smaller postoperative ventricles compared with those following an endoscopic third ventriculostomy (ETV). The impact of the final treated ventricle size on neuropsychological and quality-of-life outcomes is currently undetermined. Therefore, the authors sought to ascertain whether treated ventricle size is associated with neurocognitive and academic outcomes postoperatively. METHODS This prospective cohort study included children aged 5 years and older at the first diagnosis of hydrocephalus at 8 Hydrocephalus Clinical Research Network sites from 2011 to 2015. The treated ventricle size, as measured by the frontal and occipital horn ratio (FOR), was compared with 25 neuropsychological tests 6 months postoperatively after adjusting for age, hydrocephalus etiology, and treatment type (ETV vs shunt). Pre- and posttreatment grade point average (GPA), quality-of-life measures (Hydrocephalus Outcome Questionnaire [HOQ]), and a truncated preoperative neuropsychological battery were also compared with the FOR. RESULTS Overall, 60 children were included with a mean age of 10.8 years; 17% had ≥ 1 comorbidity. Etiologies for hydrocephalus were midbrain lesions (37%), aqueductal stenosis (22%), posterior fossa tumors (13%), and supratentorial tumors (12%). ETV (78%) was more commonly used than shunting (22%). Of the 25 neuropsychological tests, including full-scale IQ (q = 0.77), 23 tests showed no univariable association with postoperative ventricle size. Verbal learning delayed recall (p = 0.006, q = 0.118) and visual spatial judgment (p = 0.006, q = 0.118) were negatively associated with larger ventricles and remained significant after multivariate adjustment for age, etiology, and procedure type. However, neither delayed verbal learning (p = 0.40) nor visual spatial judgment (p = 0.22) was associated with ventricle size change with surgery. No associations were found between postoperative ventricle size and either GPA or the HOQ. CONCLUSIONS Minimal associations were found between the treated ventricle size and neuropsychological, academic, or quality-of-life outcomes for pediatric patients in this comprehensive, multicenter study that encompassed heterogeneous hydrocephalus etiologies.

Cognitive and Composite Behavioural Welfare Assessments of Pet Cats between the Ages of 9–22 Months, Living in Single and Multi-Cat Households

Although agonistic interactions between cats are often regarded clinically as a source of stress, there is currently limited research evidence regarding the welfare impact of keeping multiple cats as pets. The aim of this study was to compare welfare indicators between cats living in domestic single and multi-cat households, as well as between multi-cat households where agonistic behaviour was/was not reported by owners. Indicators included a spatial judgment bias task (JBT), where longer latencies to ambiguous probes are interpreted as being related to a more ‘pessimistic’ mood state, and the cat stress score (CSS), where high scores are indicative of high stress levels. Of 128 focal cats between the ages of 9–22 months, 94 were from multi-cat households, 126 had useable CSS data and 42 had JBT results suitable for analysis. CSSs were significantly lower for cats showing a more ‘pessimistic’ response in the JBT. It is possible that the cats that appeared to be the most relaxed may have been showing inactivity relating to negative affective states and/or were the least active/food motivated, and therefore slower in the JBT. CSSs were significantly higher in cats from single compared with multi-cat households, and did not vary with reports of agonistic interactions in multi-cat households. JBT results did not vary depending on the presence of, or reports of agonistic behaviours between, cohabiting cats. These data suggest that cats from single-cat households may be more likely to show signs of acute stress than those in multi-cat households. Alternative explanations are possible. For example, lower CSSs in the multi-cat group may reflect ‘relief’ effects resulting from separating cats for the test period, or inactivity relating to negative affective states. Due to the narrow sample population and broad scope of husbandry conditions, the potential for confounding variables limits the degree by which results can be used to inform causation of the relationships identified. Further research is warranted to replicate this work and explore potential confounders.

Dynamic arm movements attenuate the perceptual distortion of visual vertical induced during prolonged whole-body tilt

Concurrent body movements have been shown to enhance the accuracy of spatial judgment, but it remains unclear whether they also contribute to perceptual estimates of gravitational space not involving body movements. To address this, we evaluated the effects of static or dynamic arm movements during prolonged whole-body tilt on the subsequent perceptual estimates of visual or postural vertical. In Experiment 1, participants were asked to continuously perform static or dynamic arm movements during prolonged tilt, and we assessed their effects on the prolonged tilt-induced shifts of subjective visual vertical (SVV) at a tilted position (during-tilt session) or near upright (post-tilt session). In Experiment 2, we evaluated how static or dynamic arm movements during prolonged tilt subsequently affected the subjective postural vertical (SPV). In Experiment 1, we observed that the SVV was significantly shifted toward the direction of prolonged tilt in both sessions. The SVV shifts decreased when performing dynamic arm movements in the during-tilt session, but not in the post-tilt session. In Experiment 2, as well as SVV, the SPV was shifted toward the direction of prolonged tilt, but it was not significantly attenuated by the performance of static or dynamic arm movements. The results of the during-tilt session suggest that the central nervous system utilizes additional information generated by dynamic body movements for perceptual estimates of visual vertical.

Dividing attention increases operational momentum

When adding or subtracting two quantities, adults often compute an estimated outcome that is larger or smaller, respectively, than the actual outcome, a bias referred to as “operational momentum”. The effects of attention on operational momentum were investigated. Participants viewed a display in which two arrays of objects were added, or one array was subtracted from another array, and judged whether a subsequent outcome (probe) array contained the correct or incorrect number of objects. In a baseline condition, only the arrays to be added or subtracted were viewed. In divided attention conditions, participants simultaneously viewed a sequence of colors or shapes, and judged which color (a non-spatial judgment) or shape (a spatial judgment) was repeated. Operational momentum occurred in all conditions, but was higher in divided attention conditions than in the baseline condition, primarily for addition problems. This pattern suggests that dividing attention, rather than decreasing operational momentum by decreasing attentional shifts, actually increased operational momentum. These results are consistent with a heightened use of arithmetic heuristics under conditions of divided attention.

Visualization of Uncertainty Aids Spatial Judgments but Fails to Improve Metacognitive Efficiency

Uncertainty is an element of many decision-making tasks and inherently compromises performance. Research has found only equivocal evidence that uncertainty representations—displays that explicitly denote data quality—offset the performance costs of uncertainty. As yet, though, no work has examined the potential benefits of uncertainty displays to metacognition, display readers’ ability to assess the quality of their own decision-making processes. The current study examined the benefits of uncertainty visualization to first-order (Type 1) and metacognitive (Type 2) sensitivity in a spatial judgment task. Data revealed only small improvements in Type 1 and Type 2 sensitivity with visualized uncertainty displays, and gave no evidence of disproportionate gains to metacognition.