Cooperative responding in rats: II. Performance on fixed-ratio schedules of mutual reinforcement

Coordinated responses of 5 dyads of rats were investigated under fixed-ratio (FR) schedules of mutual water reinforcement. Coordinated responding was defined as 2 consecutive lever-presses, 1 from each of 2 rats, occurring <.5 s apart. In the FR schedules, each coordinated episode was defined as 1 response in the FR sequence. The size of FR schedules was parametrically manipulated assuming the values of FR 1, 6, 12, 18, 24, 30, 50, and 9, in this order. Each FR remained in effect until responding reached stability. Under all conditions, pairs of rats received access to water simultaneously (mutual reinforcement). Rates and proportions of coordinated responding showed a bitonic inverted U-shaped function of ratio size. Postreinforcement pauses increased systematically as the interreinforcement interval increased. Local rates and proportions increased as a function of response location within ratios. Results of a control condition with relaxed temporal constraints for mutual reinforcement showed decreases in rates and proportion of coordinated responses, suggesting that the coordinated responses were controlled by the mutual reinforcement contingencies. The present experiment showed that coordinated responding is quantitatively affected by 3 properties of FR schedules: response requirement, reinforcement rates, and proximity to reinforcement.     

COCAINE ADDICTS AND THEIR FAMILIES: AN EMPIRICAL STUDY OF THE PROCESSES OF IDENTIFICATION

The processes of identification between adolescent cocaine addicts and their parents were studied in 402 subjects, in total 134 familial triads (father"mother"son), subdivided into two groups of 67 triads, one of these groups having as the child an adolescent of masculine sex dependent on cocaine and the other, equal in number, being a control group, duly matched for age and socio-economic status. The instrument employed was the Rorschach test (1922), limited to the application of the Lerner Defense Scale (LDS; Lerner & Lerner, 1980). The findings in the affected triads showed up as consistent statistically for the presence of intense processes of pathological identification, especially between father and son, a sign of the importance of the presence of disturbances of paternal function in the development of this addiction. The utilisation of very regressive defence mechanisms, above all of projective identification, was the predominant mode of procedure in triads with a dependent child. In comparisons between the fathers the odds ratio (OR) for projective identification was 8.66 to 1, which points to the association between cocaine addiction and the primitive mental functioning of the fathers. With empirical methodology these findings serve to corroborate the psychoanalytical conclusions based on studies of single case studies, testifying that the dysfunctions of identificatory phenomena in familial functioning are predominant in the mental organisation of cocaine addicts.     

Differential effects of post-training muscimol and AP5 infusions into different regions of the cingulate cortex on retention for inhibitory avoidance in rats.

Adult male Wistar rats were bilaterally implanted with indwelling cannulae in four different coordinates of the cingulate cortex: (1) the anterior cingulate (AC), (2) the rostral region of the posterior cingulate (RC), (3) the upper portion of the caudal region of the posterior cingulate (UC), and (4) the lower portion of the caudal region of the posterior cingulate (LC). After recovery, animals were trained in a step-down inhibitory avoidance task (3.0-s, 0.4-mA foot shock). Either immediately, or 90 or 180 min after training, animals received a 0.5-microl infusion of vehicle (phosphate buffer, pH 7.4), of muscimol (0.5 microg), or of AP5 (5.0 microg). Retention testing was carried out 24 h after training. Muscimol was amnestic when given into any of the three coordinates of the posterior cingulate cortex 90 min after training, and when given into LC immediately post-training. In addition, AP5 was amnestic when given into UC 90 min post-training, but not when given into any other region and/or at any other time. None of the treatments had any effect when given into AC. The results suggest that memory processing of the inhibitory avoidance task is regulated by the posterior but not by the anterior cingulate cortex, through muscimol-sensitive synapses, relatively late after training. AP5-sensitive synapses appear to play a very limited role in these processes, restricted to UC.     

Lutheran Preaching and the Quest for Humanization and Planetary Justice: A Perspective from Brazil

Abstract :  Since economic globalization hides the roots of injustice and internationalizes its consequences, any attempt to preach (which necessarily means to preach justice) must address the local church and at the same time the wider global context, hence the term "planetary justice." This article describes the current approach to Lutheran preaching in Latin America and specifically the Evangelical Lutheran Church in Brazil (IECLB). The article offers the following suggestions for Lutheran preaching throughout the world: hold form and content in creative tension; present justification as liberation; strive for a biocentric, gender conscious, and planetary symbiotic homiletic.     

The contributions of visual and central attention to visual working memory

We investigated the role of two kinds of attention—visual and central attention—for the maintenance of visual representations in working memory (WM). In Experiment 1 we directed attention to individual items in WM by presenting cues during the retention interval of a continuous delayed-estimation task, and instructing participants to think of the cued items. Attending to items improved recall commensurate with the frequency with which items were attended (0, 1, or 2 times). Experiments 1 and 3 further tested which kind of attention—visual or central—was involved in WM maintenance. We assessed the dual-task costs of two types of distractor tasks, one tapping sustained visual attention and one tapping central attention. Only the central attention task yielded substantial dual-task costs, implying that central attention substantially contributes to maintenance of visual information in WM. Experiment 2 confirmed that the visual-attention distractor task was demanding enough to disrupt performance in a task relying on visual attention. We combined the visual-attention and the central-attention distractor tasks with a multiple object tracking (MOT) task. Distracting visual attention, but not central attention, impaired MOT performance. Jointly, the three experiments provide a double dissociation between visual and central attention, and between visual WM and visual object tracking: Whereas tracking multiple targets across the visual filed depends on visual attention, visual WM depends mostly on central attention.     

Ambivalent Sexism and Attitudes Toward Wife Abuse in Turkey and Brazil

Men and women in Turkey and Brazil completed the Ambivalent Sexism Inventory (Glick & Fiske, 1996) and measures of attitudes about wife abuse. In both nations hostile sexism (HS) and benevolent sexism (BS) positively correlated with attitudes that legitimize abuse. Regression analyses revealed that HS accounted for unique variance, but BS (once HS was controlled) was unrelated to wife abuse attitudes. These results: (a) add to the evidence for the cross–cultural validity of ambivalent sexism, (b) suggest that HS supports the justification of violence against wives, and (c) imply that the ostensible protectiveness of BS is contingent, failing to shield women from abuse if they are deemed to have challenged a husband's authority or violated conventional gender roles.     

NK(3) receptor agonism promotes episodic-like memory in mice

The mammalian tachykinins are a family of closely related peptides including substance P, neurokinin A, neurokinin B and, recently, also hemokinin-1. They are present in the peripheral and central nervous systems, and bind to three known neurokinin (NK) receptors, the NK(1)-, NK(2)- and NK(3) receptors. In both rodents and humans, NK(3) receptors are expressed in brain structures which have been associated with learning and memory. Evidence for a role of NK(3) receptors in learning and memory has been found in NK(3) receptor knockout mice. Here, we investigated the influence of the NK(3) receptor agonist, senktide (0.1, 0.2 and 0.4 mg/kg), on the performance of C57BL/6 mice in a recently developed episodic-like memory task. Since a promnestic effect of senktide was expected, we employed an experimental protocol that provided sub-optimal learning conditions for episodic-like memory. The results indicate that senktide promotes episodic-like memory in mice in a dose-dependent manner, providing, for the first time, evidence for an involvement of NK(3) receptors in episodic-like memory.     

Perceived behavioral changes in early multiple sclerosis

Acquired behavioral changes have essentially been described in advanced multiple sclerosis (MS). The present study was designed to determine whether behavioral modifications specifically related to the MS pathological process could be identified in the initial phase of the disease, as compared to control patients with chronic, relapsing and progressive inflammatory disorders not involving the central nervous system (CNS). Eighty-eight early MS patients (Expanded Disability Status Scale score 相似文献   

Is optimal vision required for the successful execution of an interceptive task?

The importance of optimal visual function in demanding interceptive tasks is far from established. The aim of the study was to determine whether induced myopic blur and hence sub-optimal visual function would give rise to a detrimental effect on performance in the execution of an interceptive task. The batting performance of grade level cricket players was assessed facing a bowling machine whilst wearing contact lenses of four different refractive conditions (plano (nil), +1.00, +2.00 and +3.00D over-refraction), inducing increasing amounts of myopic blur. Performance for each condition was assessed based both on the shot quality against each delivery judged by a qualified cricket coach blind to each condition, along with an evaluation of the quality of ball-bat contact for each delivery. No significant change was found in batting performance with the introduction of +1.00 and +2.00D of induced myopic blur. A +3.00D over-correction was required before any significant decrease in batting performance was detected, demonstrating that batters needed to be essentially legally blind (as simulated through the use of the +3.00D over-refraction) before there was any significant measurable decrement in batting performance. We concluded that optimal visual correction is not necessarily required for optimal performance in a demanding interceptive task, and that the human perceptual-motor system is capable of compensating for marked alterations in input.     

Association among items from the self-report version of the Hamilton Depression Scale (Carroll Rating Scale) and respondents' sex

The association among items of the self-reported version of the Hamilton Depression Scale (Carroll Rating Scale), answered according to a memory of a maximally disturbing event experienced, and respondents' sex was examined in a nonclinical sample of 320 college students, 164 women (M age=21.7 yr., SD=3.6) and 156 men (M age=23.5 yr., SD=5.8). An assessment of sex bias was also evaluated. Multiple regression analysis showed that statements regarding unhappiness, urge to cry, dizziness and faintness, and waking in the middle of the night were significantly associated with women. Removal of these items from the Carroll Rating Scale Total scores eliminated the sex differences in depression rates. Items that displayed significant sex bias were those regarding behavior and emotions commonly attributed to women within the general population.