Anticipating by pigeons depends on local statistical information in a serial response time task

Pigeons responded in a serial response time task patterned after that of M. J. Nissen and P. Bullemer (1987) with humans. Experiment 1 produced global facilitation: Response times in repeating lists of locations were faster than when locations were random. Response time to a spatial location was also a function of both that location's 1st- and 2nd-order local predictability, in rough agreement with the Hick-Hyman law, according to which response time is a linear function of amount of information. Experiment 2 showed that both local and global facilitation is limited to moderate response-to-stimulus intervals of about 0.50 to 2.00 s. Experiment 3 showed that response time did not depend on global statistical information. Overall, local and global performances depended on local statistical information, but global performance did not depend on global information. Local facilitation was interpreted in plain English as anticipating.     

Haste does not always make waste: Expertise,direction of attention,and speed versus accuracy in performing sensorimotor skills

In two experiments, we examined the attentional mechanisms governing sensorimotor skill execution across levels of expertise. In Experiment 1, novice and expert golfers took a series of putts under dual-task conditions designed to distract attention from putting and under skill-focused conditions that prompted attention to step-by-stePperformance. Novices performed better under skill-focused than under dual-task conditions. Experts showed the opposite pattern. In Experiment 2, novice and expert golfers putted under instructions that emphasized either putting accuracy or speed—the latter intended to reduce the time available to monitor and explicitly adjust execution parameters. Novices putted better under accuracy instructions. Experts were more accurate under speed instructions. In agreement with theories of skill acquisition and automaticity, novice performance is enhanced by conditions that allow for on-line attentional monitoring (e.g., skill-focused or accuracy instructions) in comparison with conditions that prevent explicit attentional control of skill execution (e.g., dual-task or speed constraints). In contrast, the proceduralized skill of experts benefits from environments that limit, rather than encourage, attention to execution.     

Modeling age and retest processes in longitudinal studies of cognitive abilities

Mixed effects models were used to examine the separate effects associated with age and retest on changes in various cognitive abilities. Individuals (N > 800) ranging in age from 40 to 70 years at the 1st measurement occasion were assessed with measures of memory, spatial abilities, and speed on 4 occasions. All cognitive abilities showed decline associated with increased age and improvement across the 4 measurement occasions. The age-related effects were similar across variables, but the practice effects were largest for memory and smallest for speed. When retest effects were not included in the models, the age-related effects were underestimated, with the magnitude of bias depending on the size of the ignored retest effects. It is suggested that both age and retest should be modeled simultaneously when analyzing longitudinal data because part of the change across occasions may be attributable to practice or reactive effects.     

Bilateral facilitation of motor control in chronic hemiplegia

The present study addressed the efficacy of concurrently moving both arms, with and without a load added to the uninvolved arm, in facilitating the quality of movement of the involved side in individuals with moderate, chronic hemiplegia. Six hemiplegic cerebrovascular accident (CVA) subjects with left-hemisphere lesions participated in the study. The four males and two females ranged from 46 to 77 years of age and 30–96 months post-CVA. All subjects scored at least 70% on the Fugl-Meyer test of motor function. The task was to perform discrete unilateral and bilateral elbow extensions in the horizontal plane. The movements were 45° in amplitude and were to terminate in a 10° target zone that was indicated by an illustration of a coffee mug. The instructions were to move toward the mug as smoothly as possible in a movement time (MT) determined to be 20% longer than their minimal MT for that distance. The primary dependent variable was the percentage of continuous vs. discontinuous trajectories observed in each condition, based on whether or not a transient hesitation or reversal was observed. Phase of peak velocity was also quantified as a general indication of the symmetry of the velocity profile. Three of the six subjects exhibited a greater percentage of continuous movements of the involved arm in the nonloaded bilateral condition than the unimanual condition. Five subjects benefited when the uninvolved arm was inertially loaded in the bilateral condition when compared with unimanual performance. Only the oldest subject failed to exhibit facilitation. Peak velocity phase tended to normalize toward symmetry in the bilateral conditions. These findings are consistent with prior evidence that the control of the involved arm improves during bimanual performance for some hemiplegic subjects. It further suggests loading the uninvolved arm may benefit some subjects with respect to unimanual performance, with age perhaps playing a role in determining efficacy.     

When paying attention becomes counterproductive: impact of divided versus skill-focused attention on novice and experienced performance of sensorimotor skills

Two experiments examined the impact of attention on sensorimotor skills. In Experiment 1, experienced golfers putted under dual-task conditions designed to distract attention from putting and under skill-focused conditions that prompted attention to step-by-step putting performance. Dual-task condition putting was more accurate. In Experiment 2, right-footed novice and experienced soccer players dribbled through a slalom course under dual-task or skill-focused conditions. When using their dominant right foot, experts again performed better in the dual-task condition. However, when using their less proficient left foot, experts performed better in the skill-focused condition. Novices performed better under skill-focus regardless of foot. Whereas novices and the less-proficient performances of experts benefit from online attentional monitoring of step-by-step performance, high-level skill execution is harmed.     

布洛贝尔的诺贝尔奖:想象变成了现实

1980年,克丽丝·纽丝兰—沃哈德和埃里克·韦乔斯开始研究果蝇中的胚胎致死突变,这项研究后来获得了诺贝尔奖,在某种意义上,它标志着生物学一个富有魅力的理论时代的终结和缺乏想象力的事实时代的到来(这个短语出自于Ｔ.Ｈ.赫胥黎,他认为悲剧就是“富有魅力的理论被缺乏想象力的事实所扼杀”)。如果沃森和克里克的ＤＮＡ双链结构模型显示了想象力(只具有不多的事实)可以超越自然,那么,纽丝兰—沃哈德和韦乔斯的饱和筛选法则表明进化能够产生如此难以想象的复杂的生物学机制,以致如果以直觉的方法来研究它们,既使不是可笑的,也是毫无用处的。…     

Reviews of current books

Pastoral Psychology -     

Parapsychology and religion: The case for the paranormal

Pastoral Psychology -     

Climate perceptions matter: a meta-analytic path analysis relating molar climate,cognitive and affective states,and individual level work outcomes

Although workplace climate has been extensively studied, the research has not led to firm conclusions as to its relationship with individual level work outcomes. The authors used C. Ostroff's (1993) taxonomy to organize dimensions labeled as workplace climate and then used meta-analytic techniques to test a path analytic model. The model posited that climate affects individual level outcomes through its impact on underlying cognitive and affective states. An extensive literature search yielded 51 empirical studies with 70 samples. The results suggest that the 3 higher order facets of climate (affective, cognitive, and instrumental) affected individual level outcomes of job performance, psychological well-being, and withdrawal through their impact on organizational commitment and job satisfaction.