Conjugate lateral eye movement and latency of verbal response to arithmetic questions.

24 left movers, 24 right movers and 24 mixed movers, categorized on the basis of their conjugate lateral eye movements, were measured on latency of verbal response to arithmetic questions. The predicted superiority of right movers in speed of response did not occur nor did interference with habitual direction of conjugate lateral eye movement affect results. However, the mixed group took longer to response to a second series of questions than did the left and right movers. This post hoc finding may indicate inefficient hemispheric competition within the mixed group when subjects are asked to add another task to that of arithmetic problem-solving.     

Affective responses to movie posters: differences between adolescents and young adults

Although the link between cognition and affect in the advertising context has been demonstrated in several studies, no research to date has considered adolescents’ affective responses to movie posters and their attitudes to negative and positive images. A 2 (between subjects) × 4 (within subjects) mixed‐factorial experiment design comprising two groups of subjects (80 adolescents and 80 young adults) and four advertising stimuli (two highly positive images and two highly negative images) was used to test the differences in the subjects’ attitudes to advertising, positive and negative affect, and viewing intentions. Although the adolescents, compared to the young adults, did not appear to have significantly stronger attitudes to emotional advertisements (ads), they showed a similar level of intensity of affective response when exposed to negative and positive images.     

Preference for mixed versus constant delays of reinforcement: Effect of probability of the short, mixed delay

Preference for mixed versus constant delays of reinforcement was studied with a concurrent-chain procedure. Lever pressing by rats in concurrently available variable-interval 60-second initial links occasionally produced mutually exclusive terminal-link reinforcement delays. A constant delay of reinforcement (either 15 seconds or 30 seconds) composed one terminal link and mixed delays (.2 second and twice the value of the constant delay) were arranged in the other terminal link. The proportion of .2-second delays in the mixed-delay terminal link took on values of 0, .1, .25, .5, .75, .9, and 1.0 over experimental conditions. Based on relative rates of responding in the initial links, preference for the mixed delays was a negatively accelerated function of the proportion of short, mixed delays. Three of five rats preferred the mixed delays to the constant delays when the proportion of short, mixed delays was .1 or higher, and all five rats preferred the mixed delays when the proportion of short, mixed delays was .25 or higher. Neither Squires and Fantino's (1971) delay-reduction model of choice nor a model based on the harmonic mean reinforcement delay provided a close estimate of choice proportions over the range of short-delay proportions studied. The delay-reduction model underestimated choice for the mixed delays at low and intermediate proportions of short delays, and the harmonic-mean-delay model overestimated choice for the mixed delays at intermediate and high proportions of short delays.     

Co-occurring disorders among mentally ill jail detainees. Implications for public policy.

Studies have demonstrated that police often arrest the mentally ill when treatment alternatives would be preferable but are unavailable. Thus, jails may contain disproportionate numbers of severely mentally ill persons who have co-occurring disorders. Data on the co-occurrence of severe mental disorder, substance abuse, and antisocial personality disorders were gathered from 728 randomly selected male urban jail detainees. Using difference of proportions tests and loglinear analysis, the authors demonstrated that most subjects with a severe mental disorder (schizophrenia or a major affective disorder) also meet criteria for a substance abuse or antisocial personality disorder. These findings suggest several changes in public policy regarding health care delivery in correctional settings and for the general population.     

Further evidence for mixed emotions

Emotion theorists have long debated whether valence, which ranges from pleasant to unpleasant states, is an irreducible aspect of the experience of emotion or whether positivity and negativity are separable in experience. If valence is irreducible, it follows that people cannot feel happy and sad at the same time. Conversely, if positivity and negativity are separable, people may be able to experience such mixed emotions. The authors tested several alternative interpretations for prior evidence that happiness and sadness can co-occur in bittersweet situations (i.e., those containing both pleasant and unpleasant aspects). One possibility is that subjects who reported mixed emotions merely vacillated between happiness and sadness. The authors tested this hypothesis in Studies 1-3 by asking subjects to complete online continuous measures of happiness and sadness. Subjects reported more simultaneously mixed emotions during a bittersweet film clip than during a control clip. Another possibility is that subjects in earlier studies reported mixed emotions only because they were explicitly asked whether they felt happy and sad. The authors tested this hypothesis in Studies 4-6 with open-ended measures of emotion. Subjects were more likely to report mixed emotions after the bittersweet clip than the control clip. Both patterns occurred even when subjects were told that they were not expected to report mixed emotions (Studies 2 and 5) and among subjects who did not previously believe that people could simultaneously feel happy and sad (Studies 3 and 6). These results provide further evidence that positivity and negativity are separable in experience.     

Contribution of lexico-semantic processes to verbal short-term memory tasks: a PET activation study

Recent studies have demonstrated the intervention of long-term memory processes in verbal STM tasks and several cognitive models have been proposed to explain these effects. A PET study was performed in order to determine whether supplementary cerebral areas are involved when subjects have to execute short-term memory tasks for items having representations in long-term memory (in comparison to items without such representations: words vs non-words). Results indicate that verbal STM for words specifically involves the left middle temporal gyrus (BA 21) and temporo-parietal junction (BA 39). These areas can be associated with lexical and semantic processes. These results are in agreement with cognitive models that postulate the simultaneous influence of lexical and semantic long-term representations on verbal STM processes and/or a lexico-semantic buffer.     

Intelligence and selective attrition in a nationally representative and longitudinal sample of Americans

Selective attrition is a potentially serious problem that can bias the findings that are generated from longitudinal samples. Although the extent to which IQ might be involved in selective attrition has been studied, the results from these studies have been decidedly mixed. The current study adds to the literature examining the link between IQ and selective attrition by examining four waves of data from the National Longitudinal Study of Adolescent Health. Analysis of these data revealed that IQ is related to attrition, with lower IQ respondents more likely to drop out of the study when compared against higher IQ respondents. The evidence suggests that dropouts score about 4.5 IQ points lower than subjects who did not drop out. Limitations of the study are noted and directions for future research are discussed.     

Apraxia differs in corticobasal degeneration and left-parietal stroke: A case study.

Corticobasal degeneration (CBD) is a progressive disorder characterized by both cortical and basal ganglia dysfunction such as asymmetrical apraxia, and akinetic rigidity, involuntary movements, and cortical sensory loss. Although apraxia is a key finding for the differential diagnosis of CBD, it has not been determined whether the features of apraxia seen in subjects with CBD are similar to those features exhibited by subjects with left-hemisphere damage from stroke. Therefore, for both clinical purposes and in order to better understand the brain mechanisms that lead to apraxia in CBD, we studied praxis in a patient with CBD and compared him to patients who are apraxic from left-parietal strokes. We used three-dimensional movement analyses to compare the features of apraxic movement. This subject with CBD was a dentist whose initial complaint had been that he "forgot" how to use his tools in the mouths of his patients. Analyses were performed on the trajectories made when using a knife to actually slice bread, and when repetitively gesturing slicing made to verbal command. Movements of the left hand, wrist, elbow, and shoulder were digitized in 3-D space. Although the CBD subject was clearly apraxic, the features of his apraxia differed markedly from those of the subjects with lesions in the left parietal lobe. For movements to command, the CBD subject showed joint coordination deficits, but his wrist trajectories were produced in the appropriate spatial plane, were correctly restricted to a single plane, and, like control subjects, were linear in path shape. However, when he was actually manipulating the tool and object, all of these aspects of his trajectories became impaired. In contrast, the deficits of the apraxic subjects with left-parietal damage were most pronounced to verbal command with their movements improving slightly although remaining impaired during actual tool and object manipulation. Unlike patients with parietal strokes, patients with CBD have degeneration in several systems and perhaps deficits in these other areas may account for the differences in praxic behavior.     

Blood and injection phobia: background and cognitive, physiological, and behavioral variables.

Blood-phobic (n = 81) and injection-phobic (n = 59) patients fulfilling the DSM-III-R criteria for simple phobia were compared on a number of variables. There were no differences between the samples in age at onset, age at treatment, marital and occupational status, history of fainting in the phobic situation, and impairment. Higher proportions of blood-phobic subjects than of injection-phobic subjects reported having first-degree relatives with the same phobia (61% vs. 29%) and reported fearing that they were going to faint in the phobic situation (77% vs. 48%). In both samples, these proportions were higher in the subgroup with a history of fainting. Injection-phobic subjects rated 2 of 11 physiological items higher than did blood-phobics subjects, but the groups did not differ on behavioral variables. Overall, the similarities were more marked than the differences, and it is suggested that these two specific phobias should be regarded as one diagnostic entity.     

Classifying simulated air threats with fast and frugal heuristics

In three experiments, subjects learned to classify simulated aircraft using four probabilistic cues then classified test sets designed to contrast predictions of several compensatory and non-compensatory heuristics. Results indicated that a proportion of subjects appeared to use a non-compensatory fast and frugal heuristic but that significant proportions used less frugal compensatory decision rules. The relative proportions of subjects exhibiting responses consistent with the fast and frugal heuristic versus other decision rules was largely unaffected by manipulations of time pressure and perceived cue uncertainty. An extreme time constraint, however, did result in significant differences in the proportions of subjects who preferred non-compensatory to compensatory decision rules. These results suggest that it is possible to model multi-attribute decision tasks like threat assessment with a fast and frugal heuristic although no single heuristic is a general model for the simulated threat assessment task. Copyright © 2006 Crown in the right of Canada. Published by John Wiley & Sons, Ltd.     

Unilateral brain lesions in childhood: performance on the Revised Token Test

Comprehension of connected language as assessed by the Revised Token Test (RTT) was studied in 17 children with left hemisphere lesions (LL) and 11 with right hemisphere lesions (RL). LL children's significantly lower performance on several subtests than left controls (LC) matched by age, sex, race, and social class appeared to be related to the memory demands of these subtests rather than the limited syntactic elements assessed by the RTT. LL subjects requested significantly more command repetitions than control or RL subjects and when a repetition was not requested LL subjects often responded with immediacy. Although RL children tended to perform lower than right matched controls (RC), these differences were not significant nor readily related to either the memory or specific linguistic structures assessed. RL subjects required fewer command repetitions than LL subjects and exhibited a significantly greater frequency of immediate responses than controls or LL subjects. While based on few children, a trend for LL children with retrorolandic lesions to perform more poorly than those with left prerolandic lesions was suggested. No systematic difference in performance was apparent for children with left cortical vs. left subcortical lesions or among discrete sites of lesions within the right hemisphere. Children with left lesions prior to 1 year of age performed no better and, in several instances, significantly poorer than LL patients sustaining lesions after 1 year of age. Among RL subjects, those sustaining lesions after 1 year of age had greater difficulty than those with lesion onset before 1 year of age, especially on linguistic elements which seemed to be dependent upon visual spatial properties. Further studies are needed to evaluate the comprehension of more complex linguistic structures among children with unilateral brain lesions as well as to study the role of more basic factors such as memory and attention in explaining the present findings.     

Left hemispheric preference and alexithymia: A neuropsychological investigation

Starting from the hypothesis that alexithymics show a hyperactive left hemisphere, this study investigated the neural processing of visual information in two alexi-thymic groups and one nonalexithymic group. The subjects performed a lateralised visual-matching task, through which the proportions of ipsilateral and contralateral processing of three types of stimuli were assessed. In line with the hypothesis it was demonstrated that, in contradistinction to nonalexithymics, the two groups of alexithymics showed a left hemispheric preference in their neural processing of emotion words.     

Visual neglect and left-sided context effects

Patients with visual neglect generally fail to respond to an item placed on the left of a target location, even when both stimuli are situated in the right visual field. Little is known, however, about the level of processing for the unattended items. Two patients with left visual neglect served as subjects in several experiments measuring passive contextual effects of a left-sided item on responses to a focal target. The results reveal that a neglected item may influence the speed of responding. The findings are interpreted relative to the loci of context effects in normal subjects.     

Illusory Personal Control as a Determinant of Bet Size and Type in Casino Craps Games1

Langer's (1974, 1975) theory regarding the conditions under which subjects performing a chance task will suffer from an illusion of control over the outcome has specified 6 conditions proposed to enhance the illusion ofcontrol in chance tasks. A number of studies have applied her theory and predictions to gambling, a real‐world arena of chance tasks where participants have been observed to act as if the outcomes are controllable by the use of various “logical” (acting on the “gambler's fallacy”) and superstitious strategies (e. g., blowing on dice). Thus far, however, these studies have not been conducted in naturalistic gaming environments and have yielded mixed results regarding the operation of the illusion of control. The present research offers the first study of the operation of the illusion of control in such a real‐world context. In order to examine the effects of active vs. passive task participation (a variable hypothesized by Langer to affect the illusion of control), patrons of Reno casinos were observed placing craps bets on their own and another yoked patron's dice rolls. It was hypothesized that subjects would (a) place higher bets and (b) place more “difficult” bets (e. g., where only one specific number, as opposed to any of several numbers, may win) on their own rolls (when they would experience the illusion of control over the outcome) than on other patrons' roles (when they would not experience such an illusion). That is, players were expected to generally adopt riskier betting strategies when throwing the dice. Results supported the hypotheses.     

Nonenculturated orangutans' (Pongo pygmaeus) use of experimenter-given manual and facial cues in an object-choice task

Several experiments have been performed, to examine whether nonhuman primates are able to make use of experimenter-given manual and facial (visual) cues to direct their attention to a baited object. Contrary to the performance of prosimians and monkeys, great apes repeatedly have shown task efficiency in experiments such as these. However, many great ape subjects used have been "enculturated" individuals. In the present study, 3 nonenculturated orangutans (Pongo pygmaeus) were tested for their ability to use experimenter-given pointing, gazing, and glancing cues in an object-choice task. All subjects readily made use of the pointing gesture. However, when subjects were left with only gazing or glancing cues, their performance deteriorated markedly, and they were not able to complete the task.     

Melloration and maximization of reinforcement minus costs of behavior

Eight pigeons were exposed to independent concurrent schedules. Concurrent variable-interval 60-second variable-interval 60-second schedules were presented to one group of four subjects. Following baseline training, a limited hold was added to one of the schedules and the duration of the hold was decreased in successive conditions. Concurrent variable-interval 120-second variable-interval 40-second schedules were presented to another group of four subjects. These subjects were first exposed to decreasing durations of a limited hold in the variable-interval 40-second component. After replication of the baseline, a limited hold in the variable-interval 120-second component was decreased in duration. The initial durations of the holds were determined from the subjects' responding in the baseline conditions. A duration was chosen such that approximately 25% of the scheduled reinforcers would be canceled if responding remained unchanged.

Approximate matching of time proportions and reinforcement proportions was observed when the limited hold was added to the variable-interval 60-second schedule and when the limited hold was added to the variable-interval 40-second schedule. Time proportions were less extreme than reinforcement proportions when the limited hold operated in a variable-interval 120-second schedule. Overall reinforcement rates tended to decrease with continued training in concurrent schedules with a limited hold. Absolute deviations from time matching also decreased. The results provide evidence against the principle of reinforcement maximization, and support Herrnstein and Vaughan's (1980) melioration hypothesis.

     

The effect of lateral visual fixation on response latency to verbal and spatial questions

The results of several studies have suggested a relationship between lateral eye movements and contralateral hemispheric activation or ipsilateral inhibition. The present study investigated the effects of lateral and central eye fixation on response latency to verbal and spatial questions. Response latencies for verbal questions were significantly longer when subjects fixated to the left or centrally, as compared to the right. On spatial questions, response latencies were significantly longer in the right fixation condition than in the other conditions. The results indicate that visual fixation ipsilateral to hemispheric activation is related to slower problem solving, and suggest that eye movements during cognitive activity may have functional significance.     

Cognitive discrimination in brain-damaged adults: color vs form preference

The relative preference of color, form, and other dimensions as the basis for discrimination between stimuli has been investigated in a variety of normal and language-impaired populations. In aphasic adults, previous studies have been contradictory, and no studies of non-aphasic, brain-damaged adults have been reported. In this study color vs form preference was examined in 20 left brain-damaged, aphasic adults, 20 right brain-damaged non-aphasic adults, and 20 control subjects. Significant differences were found among all groups, with preference of color over form greatest for left brain-damaged subjects, followed by right-damaged and control subjects.     

On the control of visual word recognition: Changing routes versus changing deadlines

Two different accounts have been proposed to explain the fact that (1) an effect of word frequency is present when readers of transparent orthographies read only words aloud and (2) the effect of word frequency is eliminated when subjects name words and nonwords mixed together in a single block. In the route-shifting account, subjects shift from using a lexical route that can read only words to using a nonlexical route that can read both words and nonwords via the use of sublexical spelling-sound correspondences (hence, no word frequency effect). The essence of the second, time criterion account is that the elimination of the word frequency effect is determined by the speed with which the nonwords are processed, because subjects attempt to homogenize the point in time at which they release an articulation. These two different accounts are pitted against each other in a series of naming experiments utilizing the transparent Turkish orthography. A word frequency effect persists even when words and nonwords are mixed together, provided that nonword sets are matched so as to be named as quickly as the high-frequency words and as slowly as the low-frequency words, respectively. This result is argued to be consistent with the time criterion account, but not with the unadorned route-shifting account.     

Head turning versus manual pointing to auditory targets in normal subjects and in subjects with right parietal damage.

Head turning and manual pointing to auditory targets have been studied in normal subjects and in subjects with right parietal damage. Important differences were found between these two types of movement. (1) In brain-damaged subjects, audiospatial manual pointing deficit patterns and audiospatial head turning deficit patterns were dissociated. Moreover, head turning deficits tended to appear peripherally in both auditory hemifields, while manual pointing deficits tended to appear unilaterally in the left hemifield. (2) In normal subjects, at all tested eccentricities in both hemifields, head turning performances showed a characteristic undershooting of auditory targets when compared to manual pointing. Results are discussed in terms of differences between the processes underlying audio-motor tasks that involve the head and tasks that involve the hands.