Components of Random Generation by Normal Subjects and Patients with Dysexecutive Syndrome

The study presents a hypothesis on how randomness could be simulated by human subjects. Three sources of deviation from randomness are predicted: (1) the preferred application of overlearned production schemata for producing sequences of digits, (2) a wrong concept of randomness, and (3) the impossibility to monitor for redundancies of higher- than those of first-order. Deviations of random generation of digits produced by healthy subjects, patients with chronic frontal lobe damage, and patients with Parkinson′s disease from random sequences produced by a computer program can be explained by the differential influence of these factors. Whereas incorrect concepts of randomness and limits on monitoring capacity distinguished all sequences produced by humans from actual random sequences, persistence on a single production strategy distinguished brain-damaged patients from controls. Random generation of digits appears to be a theoretically transparent and clinically useful test of executive function.     

Motor functions of the basal ganglia

Summary A study of movement disorders such as Parkinson's disease and Huntington's disease can provide an indication of the motor functions of the basal ganglia. Basal-ganglia diseases affect voluntary movement and can cause involuntary movement. Deficits are often manifested during the coordination of fine multi-joint movements (e. g., handwriting). The disturbances of motor control (e.g. akinesia, bradykinesia) caused by basal-ganglia disorders are illustrated. Data suggest that the basal ganglia play an important role in the automatic execution of serially ordered complex movements.     

Interference with visual short-term memory

Working memory (Baddeley and Hitch 1974) incorporates the notion of a visuo-spatial sketch pad; a mechanism thought to be specialized for short-term storage of visuo-spatial material. However, the nature and characteristics of this hypothesized mechanism are as yet unclear. Two experiments are reported which examined selective interference in short-term visual memory. Experiment 1 contrasted recognition memory span for visual matrix patterns with that for visually presented letter sequences. These two span tasks were combined with concurrent arithmetic or a concurrent task which involved manipulation of visuo-spatial material. Results suggested that although there was a small, significant disruption by concurrent arithmetic of span for the matrix patterns, there was a substantially larger disruption of the letter span task. The converse was true for the secondary visuo-spatial task. Experiment 2 combined the span tasks with two established tasks developed by Brooks (1967). Span for matrix patterns was disrupted by a visuo-spatial task but not by a secondary verbal task. The converse was true for letter span. These results suggest that the impairment in short-term visual memory resulting from secondary arithmetic reflects a small general processing load, but that the selective interference due to mode of processing is by far the stronger effect. Results are interpreted as being entirely consistent with the notion of a specialized visuo-spatial mechanism in working memory.     

Selective response activation can begin before stimulus recognition is complete: a psychophysiological and error analysis of continuous flow

In discussions of process models of human information processing, the continuous flow conception (Eriksen and Schultz 1979) plays a prominent role. A central prediction of this conception is that any information in a display associated with a response activates that response as soon as it becomes available in the perceptual system. If it concerns the correct response channel, then response facilitation occurs. If it concerns the incorrect response channel, then response competition occurs. To assess these mechanisms more directly, we used psychophysiological measures as well as reaction time (RT). We used the latency of the P3 component of the event related brain potential (ERP) as an index of stimulus evaluation duration, the onset of lateralized motor activity derived from the ERP as an index of selective central motor activation, and the onset of electromyographic activity as an index of the start of peripheral motor activation. Subjects were required to respond to target letters that were either flanked by letters that signalled the opposite response (incompatible arrays), by the target itself (compatible arrays), by letters not associated with a response (neutral arrays), or by no other letters (targets alone). Our results replicated the basic findings obtained in this paradigm. RTs to targets alone did not differ from RTs to compatible arrays. The latter were faster than RTs to neutral arrays, which were faster than RTs to incompatible arrays. P3 latencies were longer on incompatible than on neutral trials, and longer on compatible than on target alone trials. Incorrect central response activation on incompatible trials and correct central response activation on compatible trials, both began earlier than on target alone trials. Peripheral responding on both trial types, however, began later than on target alone trials. More incompatible but less compatible trials than neutral ones exhibited incorrect peripheral response activation. Peripheral response execution was faster and more accurate on compatible than on target alone trials, while it was slower and less accurate on incompatible than on neutral trials. These results indicate, that the flankers activated their associated response channel while display evaluation was still going on, and that response facilitation and competition occurred. After applying criteria proposed by Miller (1988), it was concluded that the set of stimulus recognition processes and the set of response activation processes cannot be regarded as independent stages of processing.     

Parenting attitudes of adolescent and older mothers

The parenting attitudes of adolescent and older mothers were assessed at 1 and 12 months postpartum to explore group differences and determine if these attitudes predicted quality of home environment and parenting behaviors at 12 months. Adolescent mothers scored significantly lower than did older mothers in empathy toward children's needs, but there were no significant group differences on three other parenting attitude constructs. There were no significant correlations between parenting attitudes at 1 month and parenting behaviors at 12 months for either group. For adolescent mothers at 12 months postpartum, the only attitude construct that was significantly related to concurrent quality of parenting was developmental expectations of the child. These and other findings are discussed in the context of current theory and intervention related to adolescent parenting.     

Identification of letters in the predesignated target paradigm: a word superiority effect for the common word the

The size of the perceptual unit used in reading was addressed using the predesignated target paradigm. Sixteen subjects viewed the following stimuli in random order: the words tee, the, tie, and toe; the nonwords eet, eht, eit, and eot; and the letters e, h, i, and o. Subjects fixated on the location of the center letter and identified the letter as e, h, i, or o, alternatives which were known to them at the onset. A word superiority effect was obtained for the common word the but not for the less common words tee, tie, and toe. The word superiority effect was attributable to bias rather than discriminability: Subjects exhibited a bias to perceive the words in this experiment as the (i.e., there was a bias to perceive h in the t e stimulus presentations). These results suggest that the common word the is processed in reading units that are larger than the letter, and that the system is biased to perceive common rather than uncommon words in data-limited conditions.     

The transference neurosis in Freud's writings

This paper reviews the evolution of the concept of transference neurosis in Freud's writings. It suggests that the language in which the concept of the transference neurosis is originally expressed by Freud includes an idea of the analyst as aggressively pursuing the analytic cure by waging a solitary battle against the patient's disease. With the representation of the death drive and the larger role accorded to sadism as its external manifestation in Freud's revised drive theory of 1920, the patient becomes the ally; resistance, in the sense of the conservative forces, not disease, in the sense of libidinal conflict, becomes the enemy. It is thus difficult to speak of a transference neurosis in the circumscribed way Freud originally meant it, and he ceased to use the term after 1926 rather than redefine it to fit his broader perspective. In this broader perspective, relative resolution of conflict replaced radical liberation of the patient from disease. That Freud did not redefine the term does not imply that he discarded it, or that we necessarily should. This paper suggests that Freud implied a functional distinction between transference as transforming agent and transference neurosis as result of that transformation. That distinction defines psychoanalytic cure in terms of the understanding of a symbolic transformation which is, through the transference neurosis, reexperienced as part of the psychoanalytic process.     

Types and correlates of blood/injury-related vasovagal syncope

This study investigated by interview, the initial syncopal episode of 103 blood/injury-related vasovagal fainters in order to examine two competing hypotheses concerning their origins. Graham (Circulation, 23, 901-906, 1961) postulated that the faint resulted when sympathetic nervous system (SNS) activity ceased on termination of a threat, leaving parasympathetic nervous system (PNS) activation unopposed. Engel [Fainting (2nd edn), 1962; Annals of Internal Medicine, 89, 901-906, 1978] proposed that when in the face of threat with SNS activation, escape is blocked, the PNS becomes activated as the conservation-withdrawal response, leading to syncope. We found cases clearly conforming to each of these formulations as well as some with characteristics of both, and some who fainted in response to blood or injury but with no perception of threat. The Graham and Engel types did not differ in terms of fear or avoidance of blood, injury, or medically-related situations nor did they differ in the frequency with which their parents reported blood/injury-related syncopal episodes. It is proposed that both may be activated by a common psychological mechanism involving cessation of a defensive posture. In contrast, the non-threat fainters showed significantly less medically-related avoidance and had a greater percentage (94%) of parents with positive faint histories.