No abstract

There is some controversy concerning whether or not the visual abilities of the newborn are mediated entirely through subcortical pathways or whether the visual cortex is functioning at birth. A critical test of cortical functioning is discrimination of orientation: orientation-selective neurons are found in the visual cortex but not in subcortical parts of the visual system. An experiment is described in which newborn infants were habituated to a square-wave grating oriented 45 degrees from vertical. After habituation, significant preferences for the novel, mirror-image, grating were found, a result which argues for some degree of visual cortical functioning at birth.

There is current concern about the level of excessive gambling in a number of countries, but problem gambling still occupies an uncertain place in the addictions field. The present paper presents results from a pilot study comparing 16 problem gamblers and 16 problem drinkers. Results from a new Attachment Questionnaire suggested that gamblers were just as strongly attached to gambling as drinkers to drinking, although they were significantly less likely to experience withdrawal symptoms. Interviews with the problem gamblers suggested that excessive attachment to gambling was maintained by cyclical processes involving strong, negative feelings associated with gambling losses, shortage of money and the need to keep the extent of gambling secret. It is proposed that these 'secondary' processes, along with primary incentive motivation and the tertiary effects of losses associated with excessive behaviour, are sufficient to explain addiction. It is further suggested that neuroadaptation, tolerance and withdrawal, often thought to be central to the process of addiction, may in fact be of comparatively little importance.