Method of Suicide in the Mentally Ill: A National Clinical Survey

Comparisons of psychiatric patients who die by suicide using different methods are scarce. We aimed to establish the methods of suicide used by those who are currently or have recently been in contact with mental health services in England and Wales (N = 6,203), and describe the social and clinical characteristics of suicides by different methods. We found that hanging, self‐poisoning, and jumping (from a height or in front of a moving vehicle) were the most common methods of suicide, accounting for 79% of all deaths. The implications of these and other findings are discussed.     

Explanation and verbalization in a computer-assisted search task

Three experiments examine the effects of two different forms of explanation on assisted performance on a complex search task. The task involves determining which of a set of factories is responsible for polluting a river by testing the river for the presence or absence of various pollutants. All subjects receive computer suggestions as to which pollutants they should test for. In addition, some subjects receive an explanation of the principle according to which the advice program works. Two forms of explanation are compared. Experiment 1 shows that subjects who are allowed to ask “why” each computer recommendation is made perform significantly better than those who are provided with a block text of explanation at the start of each trial. Experiment 2 shows that the latter type of explanation is not completely ineffective, however. Subjects who are required to verbalize following the single explanation perform significantly better than do subjects who are required to verbalize but who have not received any form of explanation. Finally, Experiment 3 shows that subjects who receive the multiple “why” explanations or the explanation/verbalization combination maintain a superior performance level on subsequent unaided trials.     

Colour vision is aligned with natural scene statistics at 4 months of age

Visual perception in adult humans is thought to be tuned to represent the statistical regularities of natural scenes. For example, in adults, visual sensitivity to different hues shows an asymmetry which coincides with the statistical regularities of colour in the natural world. Infants are sensitive to statistical regularities in social and linguistic stimuli, but whether or not infants’ visual systems are tuned to natural scene statistics is currently unclear. We measured colour discrimination in infants to investigate whether or not the visual system can represent chromatic scene statistics in very early life. Our results reveal the earliest association between vision and natural scene statistics that has yet been found: even as young as 4 months of age, colour vision is aligned with the distributions of colours in natural scenes.

Research Highlights

1. We find infants’ colour sensitivity is aligned with the distribution of colours in the natural world, as it is in adults.
2. At just 4 months, infants’ visual systems are tailored to extract and represent the statistical regularities of the natural world.
3. This points to a drive for the human brain to represent statistical regularities even at a young age.