Temporal dynamics of masked word reading

The repercussions of unconscious priming on the neural correlates subsequent cognition have been explored previously. However, the neural dynamics during the unconscious processing remains largely uncharted. To assess both the complexity and temporal dynamics of unconscious cognition the present study contrasts the evoked response from classes of masked stimuli with three different levels of complexity; words, consonant strings, and blanks. The evoked response to masked word stimuli differed from both consonant strings and blanks, which did not differ from each other. This response was qualitatively different to any evoked potential observed when stimuli were consciously visible and peaked at 140ms, earlier than is usually associated with differences between words and strings and 100ms earlier than word-consonant string differences in the visible condition. The evoked response demonstrates a qualitatively distinct signature of unconscious cognition and directly demonstrates the extraction of abstract information under subliminal conditions.     

Bilateral disadvantage: lack of interhemispheric cooperation in schizophrenia

Language anomalies and left-hemisphere dysfunction are commonly reported in schizophrenia. Additional evidence also suggests differences in the integration of information between the hemispheres. Bilateral gain is the increase in accuracy and decrease in latency that occurs when identical information is presented simultaneously to both hemispheres. This study measured bilateral gain in controls (n=20) and individuals with schizophrenia (n=10) using a lexical-decision task where word or non-word judgements were made to letter strings presented in the left visual field (LVF), right visual field (RVF) or bilaterally (BVF). Language was not abnormally lateralized in the schizophrenia group. Controls exhibited the expected decrease in latency when words were presented bilaterally. This effect was not observed in the schizophrenia group who were actually disadvantaged in this condition. The lack of bilateral gain in schizophrenia is discussed as arising from differences in the connections between areas in each hemisphere that mediate language.     

Selective attention to emotional faces following recovery from depression

This study was designed to examine attentional biases in the processing of emotional faces in currently and formerly depressed participants and healthy controls. Using a dot-probe task, the authors presented faces expressing happy or sad emotions paired with emotionally neutral faces. Whereas both currently and formerly depressed participants selectively attended to the sad faces, the control participants selectively avoided the sad faces and oriented toward the happy faces, a positive bias that was not observed for either of the depressed groups. These results indicate that attentional biases in the processing of emotional faces are evident even after individuals have recovered from a depressive episode. Implications of these findings for understanding the roles of cognitive and interpersonal functioning in depression are discussed.     

Mood regulation in depression: Differential effects of distraction and recall of happy memories on sad mood

Recent research suggests that the recall of positive memories plays an important role in mood regulation. In this study, the authors examined the ability of currently depressed, formerly depressed, and never-depressed participants to regulate sad mood through the recall of positive memories or through distraction. Although improvement in mood was found for all participants in response to distraction, under instructions to recall positive memories, never-depressed participants' moods improved, whereas formerly depressed participants' sad moods remained unchanged. It is important to note that depressed participants exhibited a worsening of their sad moods after recalling positive memories. These results suggest both that depression is associated with an impaired ability to use positive recall to regulate a sad mood and that this impairment continues to be evident following recovery.     

Organization of sex-typical patterns of defense during food protection in the rat: The role of the opponent's sex

Feeding rats defend a food item from an approaching conspecific by turning away, laterally, about 180°. Females and males use a different composition of movements and stepping patterns to perform these defensive dodges. This study was designed to examine the role of the robber's sex on the execution of sex-typical patterns of dodging. All subjects were tested with a partner of each sex. During dodging, females used the female-typical pattern of pivoting around the pelvis, and males used the male-typical midbody pivot, irrespective of the robber's sex. These findings show that the sex-typical patterns of dodging are not determined by the sex of the partner. Females and males however, differed in how they were oriented towards a same sex robber at the end of the dodge. This suggests that while male and female robbers must pose different defensive problems, these differences are dealt with by modifying the sex-typical pattern of dodging rather than by switching to the dodge pattern of the opposite sex. This further suggests that the differences in the composition of the dodge pattern in males and females are not due to extrinsic contingencies, but rather, are due to intrinsic differences in the sex-typical organization of defensive motor patterns. Aggr. Behav. 23:197–214, 1997.© 1997 Wiley-Liss, Inc.     

Violence in the community—a study of violence and aggression in homelessness and mental health day services

This study examined violence and aggression in five agencies providing day services in homelessness or mental health. Incident reporting was used to test the hypotheses that aggression is associated with alcohol problems, drug use, mental disorder, homelessness, history of violence, age and sex. Agency policies and patterns to aggressive incidents were explored. Three agencies provided a sufficient number of incidents for analysis (involving 30 ‘aggressors’). A history of violence was associated with aggression in all three agencies; alcohol problems, drug use and younger age were associated with aggression in at least one agency; no association was found for mental disorder, homelessness or sex. A degree of pattern to incidents could be discerned, with drink or drugs often involved, and exercises of authority or intervention in client altercations being particularly likely to precede aggression towards staff. A variety of incidents were reported, from verbal arguments to threats with a knife and serious physical assault. © 1997 John Wiley & Sons, Ltd.