Chronometric explorations of disordered minds

Patients with borderline personality disorder have unstable emotions, difficulty maintaining relationships and a high probability of self-inflicted damage. A recent experiment of Posner et al. that measured reaction-time differences derived from a simple task, revealed that alerting and orienting is normal in these patients. By contrast, and perhaps at the root of this personality disorder, the module responsible for cognitive conflict resolution is defective.     

Chronometric analysis of speech perception

The relationship between the phonological properties of speech sounds and the corresponding semantic entries was studied in two experiments using response time measures. Monosyllabic words and nonsense words were used in both experiments. In Experiment I. Ss were each presented with individual items and were required, in three different conditions, to respond positively if (1) the item contained a particular final consonant, (2) the item was a real word, (3) the item contained either a particular consonant or was a real word. Latencies indicated that separate retrieval of phonological and lexical information took about the same time. but that their combined retrieval was longer, indicating a serial or overlapping process. In Experiment II, Ss were presented with pairs of items, and they responded positively if (1) the two items were physically identical, (2) the two items were lexically identical (both real words or both nonsense words). Response latencies were longer for lexical than for physical matches. Lexical matches were’ significantly slower than physical matches even on the same pair of items. The results imply differential accessibility to separate loci of phonological and semantic features.     

Chronometric analysis of the posturo-kinetic programming of voluntary movement

Posturo-kinetic programming was investigated in a simple reaction time paradigm. Standing subjects performed voluntary upper limb elevations under three conditions differing by the importance of their destabilizing effect on the initial balance. Three indexes were considered: the reaction time (RT) corresponding to delay between the response signal (RS) and the onset of the upper limb acceleration at wrist level (Aw); the motor latency (ML) corresponding to delay between RS and onset of the earlier of the two accelerations at shank level (As) which was previously shown to indicate the onset of postural adjustments; and the postural anticipation (PA) corresponding to the delay between the onset of the earliest As and the onset of Aw. The results showed that the RT varied in relation to parameters of the forthcoming movement. RT variations were essentially due to differences in the PA. It appeared that the ML depended on cognitive factors while the PA depended on biomechanical ones. it is concluded that ML corresponds to the "true" reaction time while PA covers the earliest part of the motor response.     

Distribution of Programming in a Rapid Aimed Sequential Movement

Studies indicate that rapid sequential movements are preprogrammed and that preprogramming increases with complexity, but more complex sequences that require on-line programming have seldom been studied. The purpose of this investigation was to determine whether on-line programming occurs in a 7-target sequence in which there is a unique target constraint and if so, to determine how different task constraints affect the distribution of additional programming. Subjects contacted seven targets with a hand-held stylus as quickly as possible while maintaining a 90% hit rate. Initiation- and execution-timing patterns and movement kinematics were measured to determine when the additional programming took place. Results indicated that additional programming occurred before initiation and during movement to the first target when the constraint required more spatial accuracy (small target). A different type of unique target (a triple hit of one target) caused the additional programming to occur on-line one or two segments before its execution. Different positions of the unique target also affected timing patterns. Results were discussed in terms of: (1) capacity of processing; (2) control of movement variance; and (3) mean velocity as a programmed parameter in sequential aiming movements.     

Motor Programming as a Function of Constraints on Movement Initiation

Three experiments are reported that test the hypothesis that under certain conditions programming time is a function of the directional accuracy demand of a response, directional accuracy being quantified by the minimal angle subtended at the point of movement initiation by the circular targets within the response. Subjects in three simple reaction time experiments were required to tap a single target or a series of circular targets as rapidly as possible with a hand-held stylus. Experiments 1 and 3 showed that the subtended angle (SA) of a response can have a more powerful effect on programming time, as indexed by reaction time and premotor time, than the number of movement parts in the response. The results of Experiment 2 revealed that the locus of the directional accuracy effect was SA and not target size or movement distance. In all three experiments, response SA was a better predictor of programming time than was number of movement parts, target size, movement distance, movement time, and average movement velocity. The findings support the notion that constraints placed upon movement initiation by the directional accuracy demand of the task can play an important role in determining the length of the programming process.     

Chronometric studies of numerical cognition in five-month-old infants

Developmental research suggests that some of the mechanisms that underlie numerical cognition are present and functional in human infancy. To investigate these mechanisms and their developmental course, psychologists have turned to behavioral and electrophysiological methods using briefly presented displays. These methods, however, depend on the assumption that young infants can extract numerical information rapidly. Here we test this assumption and begin to investigate the speed of numerical processing in five-month-old infants. Infants successfully discriminated between arrays of 4 vs. 8 dots on the basis of number when a new array appeared every 2 s, but not when a new array appeared every 1.0 or 1.5 s. These results suggest alternative interpretations of past findings, provide constraints on the design of future experiments, and introduce a new method for probing infants' enumeration process. Further experiments using this method provide initial evidence that infants' enumeration mechanism operates in parallel and yields increasingly accurate numerical representations over time, as does the enumeration mechanism used by adults in symbolic and non-symbolic tasks.     

Chronometric comparison of actual and imaged complex movement patterns

The authors' aim in this study was to consider the functional equivalence of internal imagery, external imagery, and action execution. Sixteen elite gymnasts imaged and performed a complex gymnastic vault. Ten performers imaged from an internal perspective, and 6 used an external perspective. Although the results revealed that the time to image the entire motor task did not significantly differ from the time required to physically perform it, irrespective of the imagery perspective used, the temporal organization of the action was different within the imagery conditions than it was in the physical condition. The results do not provide support for the principle of temporal functional equivalence. The authors discuss the results in light of recent findings from the cognitive neuroscience and psychology literatures.     

Chronometric analysis of apparent spotlight failure in endogenous visual orienting

Subjects made speeded responses to peripheral luminance increments or decrements preceded by informative central precues. In 4 experiments one of these stimuli was much more likely to occur than the other. In a simple detection task, the likely and unlikely stimuli showed equivalent cuing effects. In a discrimination task (bright/dim), the likely stimuli showed cuing but the unlikely one did not (spotlight failure), and there was a tendency to make the likely response when the unlikely stimulus occurred at the cued location. In Experiment 5, the 2 stimuli were equally likely, and a choice was required. Large cuing effects were observed for both stimuli with no evidence of a speed-accuracy trade-off. A logogen-activation framework is described within which criterion and sensitivity adjustments are needed to accommodate the full pattern of results. Endogenous orienting appears to enhance processing of all stimuli at attended (relative to unattended) locations, an effect that may be masked by specific stimulus or response expectancies.     

Achilles Tendon Reflexes and Surface EMG Activity during Anticipation of a Significant Event and Preparation for a Voluntary Movement

Achilles tendon reflexes were evoked bilaterally during and shortly after an interstimulus-interval (ISI) of 4 s and expressed as percentages of an averaged control reflex. Surface EMG of the soleus muscles was recorded continuously during the ISI, and expressed as percentages of a control EMG level. Three types of tasks were introduced, according to a between subjects design. Condition I consisted of a guessing task, involving anticipation of the second stimulus (S2) and not requiring a motor response. Conditions II and III were a warned choice and simple RT task respectively, the motor response to S2 being a plantar flexion of either the left or right foot in Condition II, and a plantar flexion of the right foot in Condition III. The results can be stated as follows: 1. Anticipation of a stimulus is not sufficient for a reflex increase to occur during an ISI. Preparation for a movement seems to be a necessary condition.

2. The reflex increase during preparation is rather independent of the amount of selectivity in the preparatory process; simple and choice RT tasks yield similar results, although the mean RTs do differ.

3. A difference between the involved and non-involved legs in the simple RT task is not found in the present experiment, as opposed to other studies. The particular instruction given to the subjects could be of importance in producing this difference.

4. Reflex changes cannot simply be accounted for by changes in background EMG of the agonist, as the EMG time course shows no changes over time in either condition.

     

Chronometric comparisons of imagery to action: visualizing versus physically performing springboard dives

Motor imagery research emphasizes similarities between the mental imagery of an action and its physical execution. In this study, temporal differences between motor imagery and its physical performance as a function of performer expertise, skill complexity, and spatial ability were investigated. Physical execution times for springboard dives were compared with visualized execution times. Results indicate that physical and visualized performance times were not identical: Their relation is a function of dive complexity and diver expertise, but not their interaction. Relative to physical time, visualization time increased with increased complexity, suggesting the involvement of capacity-limited working memory. A nonmonotonic relation was found for expertise: Unlike experts or novices, visualization time for intermediates was significantly slower than physical time. These temporal differences are most consistent with schematic differences in skill representation. Intermediates may be relatively slowed by greater amounts of nonautomatized knowledge, as compared with the automatized knowledge of experts or the sparse knowledge of novices.     

Combined Effects of Movement Velocity and Duration on Programming Time: Spijkers (1989) Revisited

The goal of the present study was to determine the combined effects of movement velocity and duration on motor programming. Subjects were submitted to a two-choice reaction time task that could be completed by aiming movements differing in the mean velocity at which they were to be produced as well as by their movement time. The results of the present study indicate that, in each pair of responses used, the responses having the higher mean velocity were initiated faster than those having the lower mean velocity. Contrary to Spijkers' (1989) study, the different movement time pairings did not modify the effect of movement velocity on response programming time. Moreover, the same pattern of results was observed whether or not the subjects were permitted to visually guide their ongoing movement. Thus, Spijkers' proposition, that the type of control one may use to guide an aiming movement needs to be determined before movement initiation can take place, was not confirmed.     

A Critical Analysis of the Social Advocacy Movement in Counseling

The authors present (a) an overview of the recent literature on social advocacy, (b) results of a deconstructive analysis of the philosophical and theoretical underpinnings of this movement, (c) a critical analysis of its role and function in the profession, and (d) a call to the profession. The deconstructive analysis revealed 2 major driving forces and 5 related trends; the critical analysis revealed 9 key areas of consideration. Implications and recommendations are presented.     

Chronometric evidence for memory retrieval in causal conditional reasoning: The case of the association strength effect

According to many models of conditional reasoning, correct responses to the uncertain forms affirmation of consequent (AC) and denial of antecedent (DA) rely on the retrieval of an alternative antecedent from semantic memory. The main prediction issuing from this hypothesis of online retrieval is that the associative strength of the relevant information in long-term memory affects the latency of its retrieval and then of the correct response of uncertainty to AC and DA. This prediction was tested in 64 adults who performed a syllogism evaluation task with familiar causal conditional premises. As predicted, correct responses of uncertainty to AC and DA were not only more frequent but also faster when the antecedent term was weakly rather than strongly associated with the consequent. In line with the semantic framework, we also observed that this strength effect in response times was reversed for incorrect responses of certainty to AC.     

Voluntary attention and the spacing effect

Three experiments were done to test the hypothesis that the spacing effect results from a voluntary decision by the subject to pay little attention to the second presentation (P₂) of an item when it occurs shortly after the first (P¹)- In all three experiments, the spacing of repetitions was varied. In Experiment I, allocation of attention was manipulated by pairing P₂ of some pictures with a signal that indicated high payoff for later retention. In Experiment II, attention was controlled more directly by requiring the subject, in one condition, to recite words aloud. In both experiments, the dependent variable was judged frequency. In neither experiment did the effect of the attention manipulation interact with that of the spacing of repetitions. In Experiment III, the number of eye fixations given a picture was taken to be a measure of attention. The number of fixations dropped from P₁ to P₂ to P₃, but was unaffected by the spacing of repetitions. The experiments provide no support for a voluntary attention explanation of the spacing effect.     

非自愿移民的自愿安置--市场经济条件下农村水库移民安置策略研究

移民的“意愿度”影响安置效果。提高安置时的“意愿度”可减缓移民的经济社会问题。市场经济框架下,非自愿移民可实现自愿安置。首先,项目影响人的需求发生了改变:基本需求单位缩小,群体差别化,年轻人就业的非农化与居住的城镇化意愿加大,生计中对土地依赖减弱。其次,安置条件(供给)发生了变化:补偿政策优化、补偿标准提高,土地资源约束有所缓解,区位条件在安置中日趋重要。各地探索和实践了多样化安置方式,如就地后靠、以土为本的农业安置、投亲靠友、自谋生计和社会保障等。项目影响人根据自己的需求从多样化的方案中选择适宜的安置方式,可实现自愿安置。