Control of pigeons' pecking by trace stimuli

In Experiment I, pigeons' pecking a white key was reinforced with grain when white was immediately preceded by a vertical white line on a green surround, but not by green alone. This procedure produced control of pecking by the line. Next, pecking white was reinforced after vertical line on green, but not after green alone or other orientations of the white line on green. The line-tilt dimension initially did not control pecking, a result that showed that interdimensional (line versus no line) training does not always result in dimensional control. Line-tilt control was eventually established but was accompanied by a decrease in interdimensional control. In Experiment II, interdimensional training, with or without a trace interval intervening between line on green or green alone and white, was followed by tests for line-tilt control. While interdimensional control was unaffected by the trace interval, line-tilt control tended to be less with the trace interval. This dissociation of interdimensional and dimensional control, as well as the failure of interdimensional training to produce dimensional control in Experiment I, suggests that the line stimulus is multidimensional.     

The hydra-headed Mueller-Lyer effect: A theoretical puzzle

Three experiments were conducted to examine the effects of multiple fins on the magnitude of the Mueller-Lyer illusion. All studies showed that the multiple form of the elongation illusion was greater than the average of the components and that the multiple form of the shrinkage illusion was smaller than either of the components. The pattern of results failed to support either simple addition models or more complex averaging theories of illusions. A cross-attribute summation hypothesis and a filled space hypothesis were proposed as possible explanations for the results.     

Developmental changes in the recognition and comprehension of facial expression: implications for frontal lobe function.

Children aged 6-15 years old and adults (over 18) were given three tests designed to test perception and comprehension of facial expression. In the first test subjects were given two composite symmetrical faces made from the left or right half of a normal face, the subjects' task being to indicate which composite more closely resembled the original face. In the second test the subjects matched a series of photographs from Life magazine with key photographs of one of six distinct emotions (sad, fear, happy, anger, disgust, surprise). In the third test the subjects chose a key photograph that was appropriate for the face of a faceless character in a cartoon. On the composite faces test the subjects in all groups exhibited a preference for the left visual field composite, implying that all age groups were processing the faces in a similar manner. The results of the other two tests showed that there was an improvement in the perception of facial expression between the ages of 6 and 8 years, little change until about 13 years, and then a second improvement to adult performance at about 14 years. The performance of the 8- to 13-year-old children was similar to that of adult patients with frontal lobe injuries, which could be taken as evidence that the regions of the frontal lobe involved in the performance of these tasks may not be mature until about 14 years of age.     

The role of two emotion regulation tendencies across two waiting periods

Motivation and Emotion - The distress associated with uncertainty differs in important ways from distress over clear and present stressors. Emotion regulation (ER) tendencies—namely...     

Yes,they can! Efficient physical effort mobilization according to task difficulty in schizophrenia

The current literature has largely highlighted a deficit of effort-based decision-making for reward in schizophrenia. However, not all studies have dissociated effort from reward, while other studies emphasize that difficulty is the main determinant of effort rather than reward. In this study, 33 individuals with schizophrenia and 32 healthy controls were recruited to perform a decision-making isometric force task. According to motivational intensity theory, task difficulty (i.e., required force) but not reward was manipulated from easy to impossible. Accuracy between force exerted and force required, and choice to perform a task or not were our effort measures. Clinical variables including depression, defeatist beliefs, and apathy were assessed. Our results demonstrated that the schizophrenia group chose to perform easy, moderate, and difficult tasks and exerted the necessary effort to succeed similarly to the non-clinical group. No association between effort and clinical variables was found. Our findings provide new understandings related to effort mechanisms in schizophrenia.

     

Escaping the natural attitude about gender

Alex Byrne’s article, “Are Women Adult Human Females?”, asks a question that Byrne treats as nearly rhetorical. Byrne’s answer is, ‘clearly, yes’. Moreover, Byrne claims, woman is a biological category that does not admit of any interpretation as (also) a social category. It is important to respond to Byrne’s argument, but mostly because Byrne’s argument is a paradigmatic instance of a wider phenomenon. The slogan “women are adult human females” is a political slogan championed by anti-trans activists, appearing on billboards, pamphlets, and anti-trans online forums. In this paper, I respond to Byrne’s argument, revealing significant problems with its background assumptions, content, and methodology.