Health beliefs,optimism, and health‐related decisions: A study with Hong Kong Chinese

T he Health Belief Model (HBM; Rosenstock, 1966) is the most widely used psychological theory of health‐related behaviours but its applicability to non‐Western, especially Asian, populations has not been systematically studied. The main objective of the current study was to examine the effects of components of the HBM and dispositional optimism on preventive intention in two separate samples of 220 Hong Kong Chinese adults and 340 Hong Kong Chinese adolescents. Two HBM variables, benefits and barriers, were experimentally manipulated for an imaginary flu outbreak and a hypothetical vaccine. Optimism in the two samples was assessed using the Chinese revised Life Orientation Test (Lai et al., 1998). Participants indicated their intention to take the hypothetical vaccine after reading information for each of the treatment combinations defined by the two HBM variables. The order of the presentation of each of the six treatment conditions was counterbalanced. Results of ANOVA showed that the effects of the two HBM variables were similar in the two groups. Higher benefits and lower barriers were associated with stronger behavioural intention to take the vaccine. The two HBM variables interacted significantly in the adolescent but not the adult sample. Among the adolescents, the difference in intention scores between low and high barriers became larger when the benefits of taking the vaccine increased. In addition, optimism had significant effect on preventive intention only among the adolescents. These findings suggest that age may be an important factor moderating the effects of HBM components as well as optimism on preventive intention in Hong Kong Chinese. Implications of these findings to future research among Chinese were discussed.     

Dissociable spatial memory systems revealed by typical and atypical human development

Rodent lesion studies have revealed the existence of two causally dissociable spatial memory systems, localized to the hippocampus and striatum that are preferentially sensitive to environmental boundaries and landmark objects, respectively. Here we test whether these two memory systems are causally dissociable in humans by examining boundary‐ and landmark‐based memory in typical and atypical development. Adults with Williams syndrome (WS)—a developmental disorder with known hippocampal abnormalities—and typical children and adults, performed a navigation task that involved learning locations relative to a boundary or a landmark object. We found that boundary‐based memory was severely impaired in WS compared to typically‐developing mental‐age matched (MA) children and chronological‐age matched (CA) adults, whereas landmark‐based memory was similar in all groups. Furthermore, landmark‐based memory matured earlier in typical development than boundary‐based memory, consistent with the idea that the WS cognitive phenotype arises from developmental arrest of late maturing cognitive systems. Together, these findings provide causal and developmental evidence for dissociable spatial memory systems in humans.     

Weak Rejection

Linguistic evidence supports the claim that certain, weak rejections are less specific than assertions. On the basis of this evidence, it has been argued that rejected sentences cannot be premisses and conclusions in inferences. We give examples of inferences with weakly rejected sentences as premisses and conclusions. We then propose a logic of weak rejection which accounts for the relevant phenomena and is motivated by principles of coherence in dialogue. We give a semantics for which this logic is sound and complete, show that it axiomatizes the modal logic KD45 and prove that it still derives classical logic on its asserted fragment. Finally, we defend previous logics of strong rejection as being about the linguistically preferred interpretations of weak rejections.     

Retrograde amnesia for visual memories after hippocampal damage in rats

It is generally believed that the hippocampus is not required for simple discrimination learning. However, a small number of studies have shown that hippocampus damage impairs retention of a previously learned visual discrimination task. We propose that, although simple discrimination learning may proceed in the absence of the hippocampus, it plays an important role in this type of learning when it is intact. In order to test the role of the hippocampus in simple discrimination learning, we performed a series of experiments utilizing a two-choice picture discrimination task. Our experiments confirm that rats readily learn simple two-choice picture discriminations after hippocampus damage. However, if such discriminations are first learned while the hippocampus is intact, subsequent hippocampus damage causes severe retrograde amnesia for the discriminations. Furthermore, retrograde amnesia for simple picture discriminations was equally severe when the interval between training and damage was 1 d or 60 d; remote picture memories are not spared. Similarly, the rule or schema underlying a recently or remotely acquired picture discrimination learning set was lost after hippocampus damage. The severity of retrograde amnesia for simple picture discriminations is negatively correlated with the volume of spared hippocampus tissue. Thus, the hippocampus plays an essential role in long-term memories supporting simple picture discriminations.