VOCAL EXPRESSION OF EMOTION:

Abstract— Acoustic properties of speech likely provide external cues about internal emotional processes, a phenomenon called vocal expression of emotion. Testing this supposition, we examined fundamental frequency (F₀) and two perturbation measures, jitter and shimmer, in short speech samples recorded from subjects performing a lexical decision task. Statistically significant differences were found between baseline and on task values and as interaction effects involving differences in trait levels of emotional intensity and the proportion of success versus failure feedback received. These results indicate that acoustic properties of speech can be used to index emotional processes and that characteristic differences in emotional intensity may mediate vocal expression of emotion     

Cultural differences in strategic behavior: a study in computational estimation

Imbo and LeFevre (2009) observed that Asians (responding in their 2nd language) selected strategies less adaptively than did non-Asians (responding in their 1st language). In the present research, we tested whether adaptive strategy selection is (a) really more resource demanding for Asians than for non-Asians or (b) more resource demanding for participants answering in a nonpreferred language. Three groups of participants were tested on a computational estimation task (e.g., 42 × 57 ≈ ?) in no-load and load conditions: 40 Belgian-educated adults who answered in their first language (Dutch), 40 Chinese-educated adults who answered in their first language (Chinese), and 40 Chinese-educated adults who answered in their second language (English). Although the Chinese were faster and more accurate than the Belgians, they selected strategies less adaptively. That is, the Chinese were less likely to choose the strategy that produced the best estimate; this was especially so when their working memory was loaded. Further, we also observed that the Chinese who answered in English were slower than the Chinese who answered in Chinese; this difference was larger for difficult strategies and under working memory load. These results are interpreted in terms of the encoding complex model, whereas the explanation for the adaptivity results is based on cultural differences in educational history.     

Paradoxical Sleep Deprivation and Sleep Recording Following Training in a Brightness Discrimination Avoidance Task in Sprague–Dawley Rats: Paradoxical Effects

Previously, we reported that posttraining paradoxical sleep deprivation (PSD) resulted in an enhancement of the subsequent avoidance performance for rats trained for 15 trials in a Y-maze brightness avoidance discrimination task. A series of experiments were conducted to try to further understand the reasons for results which were contrary to those of the bulk of the sleep-learning literature. Experiment 1 investigated the effectiveness of the PSD technique. Rats (N= 4) were sleep recorded while residing on a “swimming pool” apparatus for 24 h. Compared to their baseline values, all animals showed a very large reduction in paradoxical sleep and spent significantly more time awake. Slow-wave sleep was unchanged. In Experiment 2, proactive motor effects were tested. Rats were deprived of PS for 24 h and then tested in a hole board motor activity task. There was a slight effect of PS deprivation on the day following the PSD and no effect when the rats were retested 1 week later. Experiment 3 investigated possible proactive effects of PSD on avoidance performance. Rats exposed to PSD in the 24 h before training in the Y-maze task did not demonstrate any facilitative effect on the subsequent avoidance performance. Experiment 4 investigated the possibility that the PSD facilitative effect could be due to partial training. Rats were given 75 acquisition trials in the brightness discrimination Y-maze avoidance before being subjected to 24 h of PSD. PS-deprived animals showed superior avoidance scores compared to non-PSD controls when retested 24 h later. In Experiment 5, the same strain of rats (N= 11) were sleep recorded after exposure to a partial acquisition in a Y-maze brightness avoidance discrimination task. They were then continuously monitored for 4 consecutive days. The percent PS for the Trained rats was significantly lower than that for the Control animals. This drop in percent PS was not confined to any particular time period in the 24-h day. None of the other sleep parameters reached significance. Analyses of the present results suggest that PSD exerts its facilitative effects on posttraining consolidation processes. We present arguments suggesting that PSD can have effects opposite to those generally reported, in animals demonstrating poor avoidance abilities, in an avoidance task.     

Phonological and visual working memory in mental addition

The goal of the present research was to examine the role of working memory in mental arithmetic. Adults (n = 96) solved multidigit arithmetic problems (e.g., 52 + 3; 3 + 52) alone and in combination with either a phonological memory load (i.e., nonwords, such as gup) or a visual memory load (i.e., random pattern of asterisks). The participants solved problems presented in a vertical format significantly faster than problems presented in a horizontal format. They also solved double digit first problems (e.g., 52 + 3) more quickly than the reverse (e.g., 3 + 52), but only when the problems were presented horizontally. Performance was worse in the phonological load condition than in the visual load condition for the participants who solved problems presented horizontally, whereas performance was worse in the visual load condition than in the phonological load condition when problems were presented vertically. The present research provides evidence that both phonological and visual aspects of working memory are involved in mental arithmetic but that the role of each working memory component will depend on such factors as presentation format.