Longitudinal effects of lean production on employee outcomes and the mediating role of work characteristics

The author discusses results from a 3 year quasi-experimental field study (N = 368), which suggest negative effects on employee outcomes after the implementation of 3 lean production practices: lean teams, assembly lines, and workflow formalization. Employees in all lean production groups were negatively affected, but those in assembly lines fared the worst, with reduced organizational commitment and role breadth self-efficacy and increased job depression. A nonequivalent control group had no negative changes in outcomes. Mediational analyses showed that the negative effects of lean production were at least partly attributable to declines in perceived work characteristics (job autonomy, skill utilization, and participation in decision making). The study also shows the longitudinal effects of these work characteristics on psychological outcomes. Implications for lean production, work design, and employee well-being are discussed.     

Large-scale ensemble averaging of ambulatory impedance cardiograms

Impedance cardiography has been used increasingly to measure human physiological responses to emotional and mentally engaging stimuli. The validity of large-scale ensemble averaging of ambulatory impedance cardiograms was evaluated for preejection period (PEP), interbeat interval, and dZ/dt_(min) amplitude. We tested whether the average of “classical” 60-sec ensemble averages across periods with fixed activity, posture, physical load, social situation, and location could be accurately estimated from a single large-scale ensemble average spanning these entire periods. Impedance and electrocardiograms were recorded for about 24-h from 21 subjects. Recordings were scored by seven raters, using both methods for each subject. Good agreement (average intraclass correlation coefficient was .91) between both ensemble averaging methods was found for all three cardiac function measures. The results indicate that for unambiguous ambulatory impedance cardiograms, large-scale ensemble averaging is valid, which makes measuring prolonged changes in cardiac sympathetic activity by measuring ambulatory PEP feasible even in large epidemiological samples.     

The origins of height fear: an evaluation of neoconditioning explanations

The present research sought to establish a reliable and valid instrument for assessing the relevance of neoconditioning factors (e.g. latent inhibition, UCS inflation/revaluation, prior fear levels, prior expectancies of harm, fear and pain levels experienced during supposed learning events), in the development of human fear. Fifty-four undergraduate height-fearful students completed the new origins instrument (OQ-II), while 54 matched controls completed a modified version (OQM-II) that examined their prior experiences with heights. In general, few differences between groups were found. Height-fearful and control subjects did not differ on trait anxiety, the frequency of negative encounters with heights, the age at which these events had occurred, prior fear levels, prior expectancies of harm, or reports of UCS inflation/revaluation procedures. However, in a finding directly opposite to that expected from a conditioning account, the mean fear and pain scores reported by subjects who had experienced direct conditioning events were significantly higher in the non-fearful group than in the height-fearful group. These findings are discussed in terms of associative and non-associative models of fear.     

Psychosocial outcomes of urban African American adolescents born to teenage mothers

This is a study of psychosocial outcomes of adolescents born to teenage mothers. Adolescents' problem behaviors, psychological well-being, social support, school variables, and sexual behaviors are compared across three groups—those born to mothers 17 or younger, mothers 18–19 years old, and mothers 20 or older. Analyses from two samples of African American adolescents from Maryland (n = 205) and Michigan (n = 570) are reported. The results from both samples indicate that mother's age at birth is unrelated to adolescents' psychosocial outcomes. These two studies add to the limited number of analyses that examine adolescent outcomes for children of teen mothers. The results suggest that efforts to understand social structural determinants of healthy and problematic adolescent development may be more informative than examining the effects of mother's age. They also suggest that teen pregnancy prevention programs may be more effective if they are part of a larger prevention strategy that incorporates social structural change efforts and not only a focus on individual level change.     

Social and environmental factors influence the suppression of pup-directed aggression and development of paternal behavior in captive meadow voles (Microtus pennsylvanicus)

During summer, female meadow voles (Microtus pennsylvanicus) maintain territories and males do not engage in paternal care. As day length shortens, territories dissolve and males nest with females and young. Because paternal behavior has never been studied in free-living meadow voles during colder months or in the laboratory under short photoperiods, the authors examined whether males housed in short day (SD) lengths exhibited more frequent or better quality paternal behavior than males housed in long day (LD) lengths. Sexually and parentally inexperienced (naive) SD males exhibited proportionally more and qualitatively better paternal care than naive LD males. SD males were more responsive than LD males to classic social cues associated with prepartum aggression inhibition and paternal onset. SD sires also displayed qualitatively better paternal behavior than LD sires. These data suggest that meadow vole paternal state is regulated by specific social and environmental cues that may contain reliable information about ecological conditions that favor paternal care.     

Acquired ‘theory of mind'' impairments following stroke

The ability to attribute thoughts and feelings to self and others (‘theory of mind') has been hypothesised to have an innate neural basis and a dedicated cognitive mechanism. Evidence in favour of this proposal has come from autism; a brain-based developmental disorder which appears to be characterised by impaired theory of mind, despite sometimes good general reasoning skills/IQ. To date no case of specific acquired theory of mind impairment has been reported. The present study examined theory of mind in adults who had suffered right hemisphere stroke, a group known to show pragmatic and social difficulties. In one study using story materials and two using cartoons, patients' understanding of materials requiring attribution of mental states (e.g. ignorance, false belief) was significantly worse than their understanding of non-mental control materials. Data from healthy elderly subjects, and a small group of left hemisphere patients (who received the tasks in modified form), suggest that this impairment on mental state tasks is not a function of task difficulty. The findings support the notion of a dedicated cognitive system for theory of mind, and suggest a role for the healthy right hemisphere in the attribution of mental states.     

Differential effects of shared attention on perception of heading and 3-D object motion

When a person moves in a straight line through a stationary environment, the images of object surfaces move in a radial pattern away from a single point. This point, known as thefocus of expansion (FOE), corresponds to the person’s direction of motion. People judge their heading from image motion quite well in this situation. They perform most accurately when they can see the region around the FOE, which contains the most useful information for this task. Furthermore, a large moving object in the scene has no effect on observer heading judgments unless it obscures the FOE. Therefore, observers may obtain the most accurate heading judgments by focusing their attention on the region around the FOE. However, in many situations (e.g., driving), the observer must pay attention to other moving objects in the scene (e.g., cars and pedestrians) to avoid collisions. These objects may be located far from the FOE in the visual field. We tested whether people can accurately judge their heading and the three-dimensional (3-D) motion of objects while paying attention to one or the other task. The results show that differential allocation of attention affects people’s ability to judge 3-D object motion much more than it affects their ability to judge heading. This suggests that heading judgments are computed globally, whereas judgments about object motion may require more focused attention.     

One extreme or the other or perhaps the golden mean? Issues of spatial resolution in face processing

The findings of some of the key studies that have examined the contribution of different bands of spatial information, specified in terms of cycles per face, to face recognition, and identification are reviewed. Based on findings from studies of low-, high-, and band-pass filtering, it is concluded that neither low facial scales nor high facial scales are optimal. Instead, a center range of facial scales, approximately 8-16 cycles per face, appears to make the greatest contribution to the recognition process. A study of identification of band-pass filtered faces is reported that reinforces the view derived from the literature. This indicated that a band with a harmonic mean of 11.1 cycles per face provided the most efficient recognition, with speed and accuracy declining at lower and higher bands.     

The Effects of Leader and Subordinate Characteristics in the Development of Leader–Member Exchange Quality1

This study investigated the contribution of both subordinate and leader characteristics in the development of leader-member exchange (LMX) quality. Data from 56 subordinate-superior dyads working at a large West-coast media company revealed that subordinates high in work self-efficacy were liked more by their supervisors, perceived to be more similar to their supervisors, experienced more positive LMX quality, and were rated as better performers than subordinates low in self-efficacy. Previous job experience, was related only to one outcome; supervisor's liking of the subordinate. Subordinates initially low in self-efficacy benefited from high LMX, as evidenced by increased end-of-program self-efficacy. Perceptions of similarity between supervisor and subordinate were found to be more important to LMX quality than actual demographic similarity. Leader self-efficacy and optimism predicted subordinates' ratings of LMX quality only for female supervisors. Unexpectedly, leader self-efficacy and optimism were related to the leaders' own ratings of LMX and subordinate performance.