Rigidity in social and emotional memory in the R6/2 mouse model of Huntington's disease

Four experiments were conducted to examine social and emotional memory in the R6/2 transgenic mouse model of Huntington’s disease. First, R6/2 mice were tested in a social transmission of food preference task where they had to acquire a preference for a flavoured food (acquisition) and subsequently to learn a preference for a different flavour (shifted reinforcement). R6/2 mice performed well in the acquisition trial. However, they were impaired in the shifted reinforcement trial and perseverated on the first preference learned. Second, mice were trained in an inhibitory avoidance paradigm, with either one or two footshocks delivered during the training. WT mice given one footshock showed retention levels lower than those of mice trained with two footshocks. By contrast, there was no difference in retention levels of R6/2 mice given either one or two footshocks. Third, mice were tested in an active avoidance task that paired a mild footshock with a warning light. R6/2 mice had a strong age-dependent deficit in this task. Finally, mice were tested in a conditioned taste aversion task that paired a saccharine solution with a nausea-inducing agent (LiCl). R6/2 mice displayed normal aversion, however this was not extinguished following repeated exposure to saccharine solution alone. Our data show that while R6/2 mice have functional hippocampus-based memory, they have deficits in striatum-based memory skills. Further, social and emotional memories appear to be encoded in a rigid way that is not influenced by subsequent learning or by arousal levels.     

EDUCATION SECTION: Infant observation in Britain:The Tavistock approach

The author draws attention to something distinctive in the psychoanalytic 'air' from the early 1960s onwards: the strong emphasis upon the very early psychological, emotional and cognitive view of infants and young children. She focuses on the work of two analysts in particular, Esther Bick and Wilfred Bion, and the comparable, though differently expressed, centrality of the observational method in their work. Each explored not only the pathological picture but also the nature and integrative function of psychic containment in earliest mental life. Each also shared a preoccupation with what constituted a psychoanalytic attitude and with the process of becoming a psychoanalyst and, in Bick's case, a child analyst or psychotherapist. The author provides an historical background to the idea of observation, followed by an account, with detailed examples, of the nature of infant observation and the observational method as taught and practised at the Tavistock Clinic, London since the late 1940s, and subsequently in many other training institutions. Here the themes of Bick and Bion are constantly interrelated such that the prototype or model for the creation of emotional meaning and thought can be appreciated and learning from experience can take place.     

Augustine’s <Emphasis Type="Italic">Confessions</Emphasis>: The Story of a Divided Self and the Process of Its Unification

This article takes up William James’ observation that Saint Augustine is “a classic example” of the discordant personality or divided self, and employs E. R. Dodd’s equally classic (1927–28) article on Augustine’s “spiritual maladjustment” to explore the psychological bases, especially parental, for Augustine’s discordant personality, and to evaluate the effectiveness of Augustine’s efforts to overcome the discordancy through a personal religious conversion.     

Creating the Best Possible World: Some Problems from Parfit

It is sometimes argued that if God were to exist, then the actual world would be the best possible world. However, given that the actual world is clearly not the best possible world, then God doesn’t exist. In response, some have argued that the world could always be improved with the creation of new people and that there is thus no best possible world. I argue that this reasoning gives rise to an instance of Parfit’s mere addition paradox and should thus be rejected. Others (Robert Adams, in particular) have argued that the actual world may, in fact, be the best possible world, at least for all actual people. I argue that this reasoning gives rise to Parfit’s non-identity problem and should thus be rejected.

Rate changes in the speech of stutterers after therapy

The fluent speaking rate of nine adult male stutterers was compared before and after stuttering intervention. The subjects, ranging in age from 18 to 37 yr (mean, 25 yr, 3 mo), exhibited mild to severe stuttering prior to treatment. The only rate reduction strategy taught to subjects during intervention was to slow the first phoneme or syllable of sentences spoken. In addition, however, subjects significantly reduced their overall rate as determined by measurements made of their fluent speech at the middle of sentences, as well as overall sentence durations (excepting the first word of utterances). The data from this investigation are interpreted relative to the facilitation/simplification hypothesis.     

Developmental changes in predicting one's own span of short-term memory

Developmental changes in the accuracy of predicting one's own recall were studied, using preschool, third grade, and college subjects in Experiment 1 and third grade and college subjects in Experiment 2. Experiment 1 showed that prediction accuracy increased from the preschool to the college years, subjects were not influenced by a potential “expectancy” bias in the procedure, and only third grade subjects were influenced by the presence of norms about peer performance. Experiment 2 showed that third graders and college subjects lower their predictions in the face of “false” norm information, with college subjects being the only group to under predict actual recall in both experiments. Thus, although adults are significantly more accurate than elementary shool children in estimating short-term recall, their susceptibility to norm information suggests that even they have uncertainty about their exact capabilities.     

Effects of warm and neutral models on the attention of observational learners

The study was conducted to examine observers' attention to adults following warm and neutral interactions with them. Forty-two preschool and 36 third grade girls interacted with a pair of female models in one of three treatment conditions in which models were, respectively, warm and neutral, neutral and neutral, or warm and warm. Subiects then witnessed the models play a picture-preference game and were asked to recall the models' responses. Analyses of the children's overt attention to the models' responses revealed a greater attention to a warm model when in the presence of both a warm and neutral model and less distraction by nonsocial stimuli when at least one warm model was present. A significant positive correlation was obtained between attention to and recall of the models' responses.     

Exposure effects and associative learning

The contributions of initial stimulus affect and of associative learning to the effects of repeated stimulus exposures were examined in two experiments. Stimuli that were initially positive and stimuli that were initially negative were presented for different number of times, and subjects rated these stimuli afterward on a number of affective dimensions. In all cases, except when negative affect was associatively paired with every stimulus exposure, affective responses became increasingly more positive with increasing exposures. The results were taken to indicate that the exposure effect can overcome an initially negative stimulus affect when the conditions of the mere exposure hypothesis are satisfied. Initial stimulus affect and associative learning of affect were shown to be independent factors, the first influencing the intercept of the exposure function, the second its slope.     

Environmental determinants of altruism: The effects of stimulus overload and perceived control on helping

In an experiment designed to measure the effects of stimulus overload on altruism, 60 female subjects were randomly assigned to three stimulus conditions of 20 subjects each: (1) overload, (2) overload with perceived control, and (3) no overload. Subjects performed simultaneous proofreading and number attention tasks while at the same time listening to distracting or nondistracting background sound, and one group believed they could have the sound turned off if they desired. Following task performance, all subjects received a request for a favor from an ostensibly unrelated confederate. Although all subjects performed the tasks about equally well regardless of stimulus condition, altruism increased significantly across the three conditions. Results were discussed in terms of stimulus overload associated with the urban environment.