Temporal grouping effects in musical short-term memory

Recent theoretical accounts of verbal and visuo-spatial short-term memory (STM) have proposed the existence of domain-general mechanisms for the maintenance of serial order information. These accounts are based on the observation of similar behavioural effects across several modalities, such as temporal grouping effects. Across two experiments, the present study aimed at extending these findings, by exploring a STM modality that has received little interest so far, STM for musical information. Given its inherent rhythmic, temporal and serial organisation, the musical domain is of interest for investigating serial order STM processes such as temporal grouping. In Experiment 1, the data did not allow to determine the presence or the absence of temporal grouping effects. In Experiment 2, we observed that temporal grouping of tone sequences during encoding improves short-term recognition for serially presented probe tones. Furthermore, the serial position curves included micro-primacy and micro-recency effects, which are the hallmark characteristic of temporal grouping. Our results suggest that the encoding of serial order information in musical STM may be supported by temporal positional coding mechanisms similar to those reported in the verbal domain.     

Comparing Data Sets: Implicit Summaries of the Statistical Properties of Number Sets

Comparing datasets, that is, sets of numbers in context, is a critical skill in higher order cognition. Although much is known about how people compare single numbers, little is known about how number sets are represented and compared. We investigated how subjects compared datasets that varied in their statistical properties, including ratio of means, coefficient of variation, and number of observations, by measuring eye fixations, accuracy, and confidence when assessing differences between number sets. Results indicated that participants implicitly create and compare approximate summary values that include information about mean and variance, with no evidence of explicit calculation. Accuracy and confidence increased, while the number of fixations decreased as sets became more distinct (i.e., as mean ratios increase and variance decreases), demonstrating that the statistical properties of datasets were highly related to comparisons. The discussion includes a model proposing how reasoners summarize and compare datasets within the architecture for approximate number representation.     

Perceptions of Nepotism Beneficiaries: The Hidden Price of Using a Family Connection to Obtain a Job

Purpose

This study tested competing predictions about the impact of nepotistic hiring on perceptions of nepotism beneficiaries, focusing specifically on the performance attributions made about nepotism hires. Of particular interest is how the qualifications of the family member compared to other applicants impacts perceptions of the nepotism hire.

Methodology

Two experimental studies, using scenarios that simulated the hiring process, were conducted. Participants reviewed materials describing the hiring process for a manager and then completed a questionnaire assessing their perceptions of the person hired.

Findings

Results showed that successful performance of nepotism beneficiaries was attributed more to political skills and relationships with upper management and less to ability and effort than was the case for non-beneficiaries and that they were perceived as less competent and as having fewer characteristics of successful managers. These negative perceptions occurred regardless of the family member’s qualifications.

Implications

This study contributes to our understanding of nepotistic hiring practices. More negative performance attributions and perceptions of competence for nepotism beneficiaries may hinder their effectiveness on the job. Knowledge gained from this study may help businesses who want to hire family members of current employees to manage this process more effectively.

Originality/Value

This is one of the first studies to examine the consequences of nepotistic hiring for nepotism beneficiaries and the first study to examine how nepotistic hiring effects the performance attributions made about nepotism beneficiaries. It is also the only study to empirically examine how the qualifications of the nepotism beneficiary influence others’ reactions to them.

     

Understanding the effects of moving visual stimuli on unilateral neglect following stroke

Moving visual stimuli have been shown to reduce unilateral neglect (ULN), however, the mechanisms underlying these effects remain poorly understood. This study compared lateralised and non-lateralised moving visual stimuli to investigate whether the spatial characteristics or general alerting properties of moving visual stimuli are responsible for reducing neglect. Post-stroke left neglect patients as well as healthy and patient control subjects were tested on a computerised line bisection task under six visual stimulus conditions. The key finding was that, relative to the no stimulus condition, leftward moving and left-sided moving visual stimuli shifted neglect patients' bisection errors leftward while the non-lateralised random moving visual stimuli did not reduce neglect patients' rightward bisection errors. The results provide evidence that spatial characteristics rather than general alerting properties of moving visual stimuli reduce rightward bisection errors in ULN. Moreover, the pattern of findings strongly supports the notion that moving visual stimuli reduce neglect by capturing attention and drawing it to a spatial location rather than by activating the attentional system via superior collicular neurons.     

Kinematic assessment of treadmill running using different body-weight support harnesses

10 male collegiate runners (M age = 21.4, SD = 1.5 yr.) ran on a treadmill with no body-weight support (BWS), 20% BWS, and 40% BWS conditions. In addition, they wore three different commercially available harnesses at the 20% and 40% BWS conditions. The aim was to run on the treadmill at a fast speed while maintaining an adequate step length. The purpose was to investigate how each harness changed running gait, and the differences in running gait between the harnesses with various body-weight support. Analysis of variance indicated significant restriction of upper body torso rotation between the harnesses at the 40% BWS conditions. Body-weight support resulted in a longer stride, decreased cadence, less vertical displacement of the center of mass, and diminished hip and ankle joint excursions. These changes indicated that increased body-weight support results in longer steps with the foot contacting the belt for a shorter period of time with less leg angular changes throughout the running cycling.