Index of Subjects

Subject Index

Index of Subjects     

Listening to discourse in distracting settings: the effects of aging

Younger and older adults listened to discourse in quiet and in conversational noise, before answering questions concerning the material. Some questions required listeners to recall specific details; others were of a more integrative nature. When the listening situation was adjusted for individual differences in hearing, younger and older adults were equally adept at remembering the gist of the passages in both quiet and in two levels of noise. The two age groups also did not differ with respect to memory for specific details when listening in quiet or in a moderate level of noise, even when required to perform a concurrent task. Only at the loudest noise level did younger adults tend to recall more detail than older adults. However, when no adjustments were made to compensate for the poorer hearing of older adults (all participants tested under identical listening conditions), older adults could not recall as much detail as younger adults, either in quiet or in noise. The results indicate that the speech-comprehension difficulties of older adults primarily reflect declines in hearing rather than in cognitive ability.     

Tinnitus als soziale Infektion?

Background

11 out of 35 male employees of a central alert team with rescue coordination function developed a tinnitus disorder. This clinical case-study highlights the psychodynamic background of this accumulation.

Methods

Employees were investigated by psychometric questionnaires and semistructured psychodynamic biografical interviews. Additionally aspects of group dynamics and organisational structure were assessed.

Results

All staff members reported adverse work conditions. Medical and psychometric examination of the tinnitus patients did not reveal severe pathological findings. The interviews identified psychodynamic conflicts dealing with autonomy and regulation of self-esteem. All tinnitus patients reported a very adverse or punitive father relation and difficulties in performing a stabile male role and self-image. Group dynamics was dominated by paranoid and regressive tendencies complicated by maladaptive coping, crude perception of external facts and a pronounced experience of aggressive impulses.

Conclusion

The remobilisation of infantile powerlessness, ineffectiveness and helplessness triggered by adverse work conditions and the introduction of a new culture of personal responsibility within the work organisation together with an impaired coping of separation conflicts enforced by traumatic aspects of the relation with the father may have promoted the tinnitus symptomatology. Additionally, due to the missing awareness of the importance of such group dynamical processes the employers contributed to an increasing psychosocial distress, which promoted the accumulated manifestation of tinnitus as a conflict expressive symptom.     

Modeling task switching without switching tasks: a short-term priming account of explicitly cued performance

Switch costs in task switching are commonly attributed to an executive control process of task-set reconfiguration, particularly in studies involving the explicit task-cuing procedure. The authors propose an alternative account of explicitly cued performance that is based on 2 mechanisms: priming of cue encoding from residual activation of cues in short-term memory and compound cue retrieval of responses from long-term memory. Their short-term priming account explains the repeated cue encoding benefit, switch cost, reduction in switch cost with preparation time, and other effects. The authors develop a mathematical model of their priming account and fit it to data from 3 experiments, demonstrating that a set of basic psychological processes can produce several effects--including putative switch costs--without switching tasks.     

Speech comprehension difficulties in older adults: cognitive slowing or age-related changes in hearing?

Speech comprehension declines more rapidly in older adults than in younger adults as speech rate increases. This effect is usually attributed to a slowing of brain function with age. Alternatively, this Age X Speed interaction could reflect the inability of the older adult's auditory system to cope with speed-induced stimulus degradation. When the authors speeded speech in a way that produced minimal degradation, both age groups were equally affected. However, when speech was speeded using other methods, word identification declined more in older than in younger adults. Hence, auditory decline rather than cognitive slowing may be responsible for older adults' poorer performance in speeded conditions.     

Short and long-term motor skill learning in an accelerated rotarod training paradigm

Rodent models of motor skill learning include skilled forelimb reaching and acrobatic locomotor paradigms. This study characterizes motor skill learning in the accelerated rotarod task. Thirty Long-Evans rats (300-400 g) were trained on an accelerated rotarod (1cm/s(2)) over eight consecutive sessions (=days, 20 trials each). Improvement in rotarod velocities mastered before falling off the rod was observed within and between sessions (plateau after five sessions). Intrasession improvement was incompletely retained at the beginning of the next day's session. Over several training sessions, intrasession improvement diminished, suggesting a ceiling effect. After 1 week of pause, the rotarod skill was retained. Locomotor exercise in a running wheel for 30 min before the first rotarod session did not affect intrasession improvement. Running-wheel exposure for 6 days did not diminish the rate of rotarod skill learning (steepness of the learning curve) but improved overall performance (upward shift of curve). Video analysis of gait on the rotarod showed that rats developed a motor strategy by modifying their gait patterns during training. The data demonstrate that rotarod improvement is not the result of enhanced general locomotor ability or fitness, which are trained in the running wheel, but requires a change in the motor strategy to master the task. Accelerated rotarod training can be regarded a valid paradigm for motor skill learning over short (intrasession, minutes) and long time frames (intersession, days).     

Predictive pointing movements and saccades toward a moving target

The authors investigated whether and, if so, how velocity information is used to control predictive manual pointing movements and saccades. Participants (N = 6) intercepted an occluded moving target as if it were still visible. They kept their eyes fixated while the target moved. The target traveled over a fixed distance and changed its velocity on the way. The presentation time of the final velocity was varied. Both the eye and the hand overshot the slow target and undershot the fast target, particularly when the duration of the final velocity was short. Thus, responses were biased in the direction of the target's initial velocity. The error seemed to arise because participants did not take their latency into account when aiming at the target. Instead, they strategically aimed farther ahead when the target was fast. Amplitude was also more related to the position of velocity change than to final velocity duration. Both findings suggest that target velocity is not extrapolated but that individuals add an increment to the position of velocity change.     

Experimental tests of an attitudinal theory of the gender gap in voting

This research examined the hypothesis that gender gaps in voting stem from differences in the extent to which men and women agree with candidates' issue stances. Two initial experiments portraying candidates by their sex and attitudes and a third experiment that also included information about political party produced the predicted attitudinal gender-congeniality effect: Participants of each sex reported greater likelihood, compared with participants of the other sex, of voting for the candidate who endorsed positions typically favored more by their own sex than the other sex. In addition, this gender-congeniality effect was present among Republican and independent participants but absent among Democratic participants because Democratic men as well as women favored candidates who advocated the positions typically favored by women. Interpretation invoked the importance of group interest based on gender as an influence on women's voting.     

The Werther effect and assisted suicide

In the course of a large epidemiological study in the region of Basle, Switzerland, from 1992 to 1996, a considerable rise in suicides assisted by the right-to-die society EXIT was uncovered after wide press coverage of an assisted double suicide of a prominent couple in that region in March 1995. Further investigation revealed that the rise of assisted suicides for a period of 2 years after the critical event was statistically significant compared to the 2 years previous to the double suicide. This was especially true for women older than 65 years. Hence, the almost enthusiastic kind of reporting about this event was apt to induce imitation suicides or a "Werther-effect."     

Semantic categorization in the human brain: spatiotemporal dynamics revealed by magnetoencephalography

We examined the cortical representation of semantic categorization using magnetic source imaging in a task that revealed both dissociations among superordinate categories and associations among different base-level concepts within these categories. Around 200 ms after stimulus onset, the spatiotemporal correlation of brain activity elicited by base-level concepts was greater within than across superordinate categories in the right temporal lobe. Unsupervised clustering of data showed similar categorization between 210 and 450 ms mainly in the left hemisphere. This pattern suggests that well-defined semantic categories are represented in spatially distinct, macroscopically separable neural networks, independent of physical stimulus properties. In contrast, a broader, task-required categorization (natural/man-made) was not evident in our data. The perceptual dynamics of the categorization process is initially evident in the extrastriate areas of the right hemisphere; this activation is followed by higher-level activity along the ventral processing stream, implicating primarily the left temporal lobe.