Effects of post-operative environment on recovery from dorsal hippocampal lesions in young rats: Tests of spatial memory and motor transfer

Young rats (30 days old) were given dorsal hippocampal lesions and then housed in different conditions to assess the contribution of the environment to recovery from the effects of the lesion. They were subsequently tested on a spatial memory task and on a task requiring complex motor movements and transfer ability. Animals with lesions were inferior to sham-operates on both these tasks. Social housing and environmental enrichment improved performance on both tests, but there was no evidence for an interaction between lesion and environmental effects. The validity of using the term “recovery” in these circumstances is discussed, and called into question.     

Chimpanzee language research: Status and potential

The impact of ape-language research upon current thought pertaining to language and man in relationship to the apes is discussed within an evolutionary framework. Studies of apes can reveal certain requisites to the language skills of humans. Social adaptations are thought to be important to the evolution of those requisites. A review of ape-language research is made, with emphasis given to the problems of controls where work is doneen face with the subjects, as where Ameslan (signing) is the system employed. The need for careful definition of what is a “word,” and the need for tracing through experience how responses come to acquire meaning, hence “wordness,” is emphasized. Levels of wordness are discussed which emerge initially from basic operants and performatives. Evidence is reported in support of the conclusion that it is through direct experience, through the pragmatic application and use of instruments, and through important social relationships that word learning is facilitated. Finally, it is noted that an important step of validation in our own work is in the successful application of methods emanating therefrom to work with mentally retarded children.     

Values and the psychotherapist

One cannot live without encountering the problem of values. Certainly, one cannot go through psychotherapy without becoming involved implicitly and explicitly in the problem. Nor can one engage in psychotherapy as a therapist without bringing certain convictions about values into one's work. These convictions may or may not be specifically communicated to the patient, but they underlie the therapist's activity; they help determine the goal he sets for himself and his patient; and they are consciously or unconsciously reflected in his questions, statements or other reactions.“^1,p.1     

Perceived control in rhesus monkeys (Macaca mulatta): enhanced video-task performance

This investigation was designed to determine whether perceived control effects found in humans extend to rhesus monkeys (Macaca mulatta) tested in a video-task format, using a computer-generated menu program, SELECT. Choosing one of the options in SELECT resulted in presentation of 5 trials of a corresponding task and subsequent return to the menu. In Experiments 1-3, the animals exhibited stable, meaningful response patterns in this task (i.e., they made choices). In Experiment 4, performance on tasks that were selected by the animals significantly exceeded performance on identical tasks when assigned by the experimenter under comparable conditions (e.g., time of day, order, variety). The reliable and significant advantage for performance on selected tasks, typically found in humans, suggests that rhesus monkeys were able to perceive the availability of choices.     

Alone and without purpose: Life loses meaning following social exclusion

Four studies (N = 643) supported the hypothesis that social exclusion would reduce the global perception of life as meaningful. Social exclusion was manipulated experimentally by having a confederate refuse to meet participants after seeing their videotaped introduction (Study 1) and by ostracizing participants in a computerized ball-tossing game (Study 2). Compared to control condition and acceptance conditions, social exclusion led to perceiving life as less meaningful. Exclusion was also operationalized as self-reported loneliness, which was a better predictor of low meaning than other potent variables (Study 3). Study 4 found support for Baumeister’s model of meaning (1991), by demonstrating that the effect of exclusion on meaning was mediated by purpose, value, and positive self-worth.     

INEQUALITY,INJUSTICE AND LEVELLING DOWN

The levelling down objection is the most serious objection to the principle of equality, but we think it can be conclusively defeated. It is serious because it pits the principle of equality squarely against the welfares of the persons whose welfares or resources are equalized. It suggests that there is something perverse about the principle of equality. In this paper, we argue that levelling down is not an implication of the principle of equality. To show this we offer a defence of, and partial elaboration of, what we call a common good conception of the principle of equality, which principle favours states in which everyone is better off to those in which everyone is worse off. We contrast this with what we call a purely structural conception of the principle of equality. The common good conception of equality involves two basic components: (1) in each circumstance there exists an ideal egalitarian distribution, which distributes equally all the available good in the distribution with the highest average welfare and (2) in evaluating how just the world is, it will matter how far the actual distribution is from the ideal distribution. The ideal egalitarian distribution in the circumstance is Pareto optimal and the approximation rule implies that Pareto superior states are less unjust than Pareto inferior states. 1     

DIVINE DNA? “SECULAR” AND “RELIGIOUS” REPRESENTATIONS OF SCIENCE IN NONFICTION SCIENCE TELEVISION PROGRAMS

Through analysis of film sequences focusing on DNA in two British Broadcasting Corporation nonfiction science television programs, Wonders of Life and Bang! Goes the Theory, first broadcast in 2013, contrasting “religious” and “secular” representations of science are identified. In the “religious” portrayal, immutable scientific knowledge is revealed to humanity by nature with minimal human intervention. Science provides a creation story, “explanatory omnicompetence,” and makes life existentially meaningful. In the “secular” portrayal, scientific knowledge is changeable; is produced through technical skill in expert communities; and is ambiguous, potentially positive and negative for society. Television representations of science affect audience understandings, and this is particularly the case for nonfiction representations of science, as they are likely to be “taken more seriously” than fictional representations. The consequences of the “religious” representation of science are discussed, and it is argued that a widespread understanding of science as presented in the religious portrayal would negatively impact democracy.     

Sequential responding and planning in chimpanzees (Pan troglodytes) and rhesus macaques (Macaca mulatta)

Chimpanzees (Pan troglodytes) and rhesus macaques (Macaca mulatta) selected either Arabic numerals or colored squares on a computer monitor in a learned sequence. On shift trials, the locations of 2 stimuli were interchanged at some point. More errors were made when this interchange occurred for the next 2 stimuli to be selected than when the interchange was for stimuli later in the sequence. On mask trials, all remaining stimuli were occluded after the 1st selection. Performance exceeded chance levels for only 1 selection after these masks were applied. There was no difference in performance for either stimulus type (numerals or colors). The data indicated that the animals planned only the next selection during these computerized tasks as opposed to planning the entire response sequence.     

Modelling relative motion to facilitate intra-limb coordination

The importance of relative motion information when modelling a novel motor skill was examined. Participants were assigned to one of four groups. Groups 1 and 2 viewed demonstrations of a skilled cricket bowler presented in either 'video' or 'point light' format. Group 3 observed a single point of light pertaining to the 'wrist' of the skilled bowler only. Participants in Group 4 did not receive a demonstration and acted as controls. During 60 acquisition trials, participants in the demonstration groups viewed a model five times before each 10-trial block. Retention was examined the following day. Intra-limb coordination was assessed for the right elbow relative to the wrist in comparison to the model. The demonstration groups showed greater concordance with the model than the control group. However, the 'wrist' group performed less like the model than the 'point light' and 'video' groups, who did not differ from each other. These effects were maintained in retention. Relative motion information aided the acquisition of intra-limb coordination, while making this information more salient (through point lights) provided no additional benefit. The motion of the model's bowling arm was replicated more closely than the non-bowling arm, suggesting that information from the end-effector is prioritized during observation for later reproduction.     

Solitude without Souls: Why Peter Unger hasn’t Established Substance Dualism

Unger has recently argued that if you are the only thinking and experiencing subject in your chair, then you are not a material object. This leads Unger to endorse a version of Substance Dualism according to which we are immaterial souls. This paper argues that this is an overreaction. We argue that the specifically Dualist elements of Unger’s view play no role in his response to the problem; only the view’s structure is required, and that is available to Unger’s opponents. We outline one such non-Dualist view, suggest how to resolve the dispute, respond to some objections, and argue that ours is but one of many views that survive Unger’s challenge. All these views are incompatible with microphysicalism. So Unger’s discussion does contain an insight: if you are the only conscious subject in your chair, then microphsyicalism is false. Unger’s mistake was to infer Substance Dualism from this; for microphysicalism is not the only alternative to Dualism.