Mother-infant interactions in western Lowland Gorillas (Gorilla gorilla gorilla): spatial relationships,communication, and opportunities for social learning

This study investigated mother-infant interactions in lowland gorillas (Gorilla gorilla gorilla) with particular focus on the relative role of mothers and infants in creating situations that are potentially conducive to infant social learning. Eleven gorilla mother-infant dyads were focally observed in weekly 1-hr sessions for 12 months. Spatial relationships were affected by age as well as by ambient temperature. Although the youngest infant was encouraged by its mother to walk and climb, mothers showed little or no encouragement in other contexts. In contrast, infants were quite interested in their mothers' activities, on some occasions repeated their mother's behavior, and actively encouraged their mothers to share food, play, or follow them. These findings suggest that gorilla infants are more active than their mothers in creating situations that are potentially conducive to the acquisition of knowledge or skills.     

The effects of defendant remorse on mock juror decisions in a malpractice case

The purpose of this study was to observe the effects of defendant remorse on monetary damages awarded to a plaintiff in a malpractice case. In two experiments, the physician-defendant expressed remorse at the time of the incident and again at trial, expressed remorse at trial, explicitly demonstrated a lack of remorse at trial, or made no mention of remorse (or a lack thereof). Participants decided how much money to award to the plaintiff and evaluated both the plaintiff and the defendant on several dimensions. Participants awarded greater compensation when the physician expressed remorse at the time of the incident than in the other conditions, both when the plaintiff was the injured patient's spouse in a wrongful death suit (experiment 1) and when the patient sued on his own behalf (experiment 2). This effect of remorse was greater for males than for females (experiment 1) and for relatively severely injured plaintiffs (experiment 2).     

Extracellular signal-regulated kinase activity in the entorhinal cortex is necessary for long-term spatial memory

Lesion studies have provided evidence that the entorhinal cortex (EC) participates in spatial memory. However, the molecular cascades that underlie memory-associated changes in the EC and its specific role in spatial memory, however, have not been clearly delineated. Recently, it has been shown that activation of extracellular signal-regulated kinase (Erk, a mitogen-activated protein kinase family member) in the dorsal hippocampus is necessary for spatial memory. To examine whether similar mechanisms are used for spatial memory storage in the EC, Erk activity was inhibited after training in the Morris water maze. Bilateral infusion of the mitogen-activated protein kinase kinase inhibitor PD098059 into the EC immediately after training resulted in a memory deficit observed during a retention test performed 48 h later. This deficit was abolished with pretraining in a different water maze in which animals were able to learn the general task requirements and the appropriate search strategies. The absence of a deficit indicates that Erk activity in the EC may be involved in storing the task requirements or the search strategies. The findings presented in this article are consistent with the idea that the EC is involved in spatial memory and indicate that Erk activity is necessary for memory consolidation in this structure.     

A new group-training procedure for habituation demonstrates that presynaptic glutamate release contributes to long-term memory in Caenorhabditis elegans

In the experiments reported here we have developed a new group-training protocol for assessing long-term memory for habituation in Caenorhabditis elegans. We have replicated all of the major findings of the original single-worm protocol using the new protocol: (1) distributed training produced long-term retention of training, massed training did not; (2) distributed training at long interstimulus intervals (ISIs) produced long-term retention, short ISIs did not; and (3) long-term memory for distributed training is protein synthesis-dependent as it could be blocked by heat shock during the inter-block interval. In addition, we have shown that long-term memory for habituation is graded, depending on the number of blocks of stimuli in training. The inter-block interval must be >40 min for long-term retention of training to occur. Finally, we have tested long-term memory for habituation training in a strain of worms with a mutation in a vesicular glutamate transporter in the sensory neurons that transduce tap (eat-4). The results from these eat-4 worms indicate that glutamate release from the sensory neurons has an important role in the formation of long-term memory for habituation.     

An experimental comparison of Pycnogenol and methylphenidate in adults with Attention-Deficit/Hyperactivity Disorder (ADHD)

Twenty-four adults (24 to 53 years old) with Attention-Deficit/Hyperactivity Disorder (ADHD), Combined Type, were studied in a double-blind, placebo-controlled, crossover study of Pycnogenol and methylphenidate. Pycnogenol is an antioxidant derived from the bark of the French maritime pine tree. Methylphenidate is a standard pharmaceutical intervention for ADHD. Anecdotal reports suggest that Pycnogenol improves concentration in adults with ADHD without adverse side effects. Participants received Pycnogenol, methylphenidate, and placebo, each for three weeks, in a randomized and counterbalanced order. Although ADHD symptoms improved during treatment, neither methylphenidate nor Pycnogenol outperformed the placebo control, as measured by self-report rating scales, rating scales completed by the individual's significant other, and a computerized continuous performance test. The conservative dosage levels and relatively brief length of treatment may have contributed to the absence of significant differences among treatment conditions. Implications for future research are noted.     

Conflicts of interest in science in Armenia

The author describes problems facing Armenia in reorganization of the structure of science in the post-socialist era with the aim of utilizing limited state resources more efficiently by reducing the number of separate scientific institutes, concentrating on essential core subjects required by the nation and encouraging all other projects to compete in the international arena for grant sponsorship. An earlier version of this paper was presented at an International Conference on “Conflict of Interest and its Significance in Science and Medicine” held in Warsaw, Poland on 5–6 April, 2002.     

Cross-cultural patterns in emotion recognition: highlighting design and analytical techniques

This article highlights a range of design and analytical tools for studying the cross-cultural communication of emotion using forced-choice experimental designs. American, Indian, and Japanese participants judged facial expressions from all 3 cultures. A factorial experimental design is used, balanced n x n across cultures, to separate "absolute" cultural differences from "relational" effects characterizing the relationship between the emotion expressor and perceiver. Use of a response bias correction is illustrated for the tendency to endorse particular multiple-choice categories more often than others. Treating response bias also as an opportunity to gain insight into attributional style, the authors examined similarities and differences in response patterns across cultural groups. Finally, the authors examined patterns in the errors or confusions that participants make during emotion recognition and documented strong similarity across cultures.     

A computational account of altered error processing in older age: Dopamine and the error-related negativity

When participants commit errors or receive feedback signaling that they have made an error, a negative brain potential is elicited. According to Holroyd and Coles’s (in press) neurocomputational model of error processing, this error-related negativity (ERN) is elicited when the brain first detects that the consequences of an action are worse than expected. To study age-related changes in error processing, we obtained performance and ERN measures of younger and high-functioning older adults. Experiment 1 demonstrated reduced ERN amplitudes in older adults in the context of otherwise intact brain potentials. This result could not be attributed to uncertainty about the required response in older adults. Experiment 2 revealed impaired performance and reduced response- and feedback-related ERNs of older adults in a probabilistic learning task. These age changes could be simulated by manipulation of a single parameter of the neurocomputational model, this manipulation corresponding to weakened phasic activity of the mesencephalic dopamine system.