The impact of anxiety on visual attention to central and peripheral events

Recent reports in the literature suggest that anxious individuals show an attentional bias to mood-congruent information. Various investigators have hypothesized that such anxiety-based coding biases contribute to the maintenance of mood disorders. The present study sought to determine if attentional biases in anxious subjects extends to the perception of neutral, as opposed to affect-laden, stimuli. A procedure used to determine the locus of attention to foveal and peripheral visual events was used in combination with two inter-stimulus intervals, fixed and variable, to examine anxious and non-anxious subjects' attentional biases. Mood states were established by a well-validated musical induction procedure. The results revealed an attentional bias to foveal visual events in non-anxious subjects and an attenuated or reversed (peripheral) bias in anxious subjects. The clinical implications of these findings are discussed.     

Can we imagine how objects look from other viewpoints?

Many psychologists who study cognition believe that perception achieves object-centered representations that make it possible to extract representations of how the object would appear from differing viewpoints. Others believe we can achieve representations of how an object would appear by a process of visualization or mental rotation. We report experiments in which the subject tries to imagine how three-dimensional novel wire objects would appear from positions other than the one they are in. Subjects are unable to perform this task unless they make use of strategies that circumvent the process of visualization. It is suggested that the linear increase in time required to succeed in mental rotation tasks as a function of the angular discrepancy between the figures compared is the result of increasing difficulty rather than of the time required for rotation.     

Patterns of movement in the first 6 months of life: new directions

The field of infant perceptual development has relied heavily on the preferential-looking and habituation paradigms. Despite the obvious advantages of employing standardized methodologies, there is a need to study how perceptual variables give rise to and guide action beginning in the neonatal period. It is argued here that, in the first 5 months of life, it is important to distinguish reflexive patterns of movement from voluntary and cortically controlled patterns. Some criteria are defined. This paper describes three experiments which utilized movement counters to record developmental changes in the frequency and synchrony of limb movements in infants under 5 months. The results show that there is a general increase in frequency of limb movements from 1 to 5 months, but with a plateau or even a decrease in activity from the middle of the third month to the end of the fourth month. It was also demonstrated that synchrony scores (co-activation) for pairs of limbs showed significant increases from 1 month to 5 months. Finally, in all three experiments the presentation of an attractive toy resulted in suppression of activity. The results of the three experiments are interpreted to measure a gradual increase in cortically controlled movement patterns.     

Dynamic organization of intersensory function

Issues related to infant intersensory functioning are reviewed. The argument is offered that limitations of sensory inputs during early stages of development are necessary and provide structure and organization which determine behavioural characteristics at later stages. It is also suggested that infant organisms respond to the intensity of stimulation rather than organizational characteristics and that this is responsible for the form of sensory equivalence apparent during early development. A scheme for the investigation of sources of intersensory organization is presented which involves a prospective analysis of how consideration of the times of onset of sensory functions helps us to understand intra- and intersensory development. The advantages of this experimental approach are outlined.     

Visual search along the colour dimension

Subjects searched for a chromatic target among coloured background items. With low target-background chromatic similarity, response latencies remained uniformly short whether the target was present or not and whether the items were chromatically homogeneous or not. Latencies increased with increases in target-background similarity and were longest with heterogeneous backgrounds, with which the effects of trial type also became manifest. We employed Treisman's model of visual search to account for these findings. In particular, we suggest that similarity increases forced a shift from a preattentive to an attentive search, the latter being importantly shaped by the background's level of chromatic variance.     

The psychology of knights and knaves

Knight-knave brain teasers are about a realm in which some people, knights, tell only truths, whereas all others, knaves, tell only lies. For example, suppose person A says, "I am a knight and B is a knight," and person B says, "A is a knave." Is A a knight or a knave? Is B a knight or a knave? In a pilot study, we asked subjects to think aloud while solving problems like these. Their statements suggested that they were making assumptions about the knight/knave status of the characters and drawing deductive inferences from these assumptions to test their consistency. This encouraged us to model the process by means of a simulation based on an earlier natural-deduction theory of reasoning. The model contains a set of deduction rules in the form of productions and a working memory that holds a proof of the correct answer. The greater the number of steps (assumptions and inferences) in the proof, the greater the predicted difficulty of the puzzle. The experiments reported here confirmed this prediction by showing that subjects were more likely to make mistakes (Experiment 1) and take longer to solve (Experiment 2) puzzles associated with a larger number of proof steps.     

Topographic electroencephalographic alpha in recovered depressed elderly

Late-middle-aged and elderly normal volunteers with past histories of Major Depression according to the Diagnostic and Statistical Manual of Mental Disorders (third edition-revised) criteria were compared with sex- and age-matched control subjects using topographic electroencephalographic (EEG) indices. Healthy, euthymic recovered depressed subjects showed greater alpha amplitudes than controls. Delta, theta, and beta amplitudes did not reliably distinguish the groups. Considered in the context of previous research indicating that actively depressed subjects exhibit elevated EEG alpha compared to controls, these findings raise questions concerning state and trait conceptualizations of depression and EEG alpha.     

The 20 questions task with families of schizophrenics: divergent findings

The study attempted to replicate and extend the results of an earlier study by Wild and Shapiro (16), establishing the utility of Mosher and Hornsby's (8) 20 Questions Task as a means of differentiating families with schizophrenic patients from those of psychiatrically hospitalized but nonschizophrenic individuals. In the current study, Wild and Shapiro's original design was expanded and revised by (a) diagnosing patients using Research Diagnostic Criteria rather than hospital diagnoses and (b) including families with schizophrenic daughters and/or one-parent families, in addition to intact families with schizophrenic sons. Families were comparable on age, intelligence, and socioeconomic variables. The results failed to replicate those reported by Wild and Shapiro, and indicated that the 20 Questions Task was sensitive to differences in family constellation and offspring gender as well as offspring diagnosis. The findings suggest that forms of familial communication deviance detected with the 20 Questions Task may not be unique to families of schizophrenics, thus highlighting the need to expand research on family communication deviance in families with schizophrenic offspring to families with varied family constellations and characteristics.     

Cerebral laterality and depression: differences in perceptual asymmetry among diagnostic subtypes

Examined the influence of diagnostic subtype of depression on perceptual asymmetry for dichotic listening and visual tachistoscopic tasks. A total of 65 unmedicated patients with major depressive disorders and 30 normal controls were tested on a verbal and nonverbal task in each modality. Patients diagnosed according to the DSM-III with melancholia had abnormal perceptual asymmetry for dichotic nonsense syllable and complex tone tasks. In contrast, patients having a nonmelancholic "atypical depression" (reactivity of mood with preserved pleasure capacity and associated features) did not differ from normal controls on these tasks, but had an increased incidence of left handedness. Bipolar depression (history of hypomania) differed from unipolar depression in showing abnormal perceptual asymmetry for a tachistoscopic dot enumeration task. Alterations of perceptual asymmetry in melancholia and bipolar depression were consistent with hypothesized right hemisphere dysfunction.     

Family Functioning of Male Alcoholics and Their Female Partners during Periods of Drinking and Abstinence

Family functioning of 20 alcoholic male veterans and their female partners was assessed in relation to drinking (wet) and abstinent (dry) intervals. Repeated measures analyses performed on the McMaster Family Assessment Device (FAD) indicated that on all 7 scales of the FAD, alcoholics and their mates perceived family functioning to be better during dry than wet periods. In contrast to their alcoholic mates, female partners gave healthier ratings to all FAD scales except Roles in the dry condition and Affective Involvement in the wet condition. According to published cutoff scores for healthy and unhealthy family functioning, alcoholics as a group viewed their wet and dry family functioning as unhealthy, although the female group regarded the family's dry Problem Solving and Behavioral Control as healthy. These findings suggest that the family functioning of alcohol-involved couples is biphasic, oscillating between drinking and abstinent periods.