A comparison of the characteristics of accidental substance-related acute toxicity deaths in Canada across life stages, 2016-2017.

The acute toxicity (sometimes called "overdose" or "poisoning") crisis has affected Canadians across all stages of life, including youth, adults and older adults. Our biological risks and exposures to substances change as we age. Based on a national chart review study of coroner and medical examiner data on acute toxicity deaths in 2016 and 2017, this analysis compares the burden of deaths and circumstances of death, locations of acute toxicity event and death, health history and substances contributing to death of people, by sex and life stage.

Accidental substance-related acute toxicity deaths among youth in Canada: a descriptive analysis of a national chart review study of coroner and medical examiner data.

Introduction: Substance-related acute toxicity deaths (ATDs) are a public health crisis in Canada. Youth are often at higher risk for substance use due to social, environmental and structural factors. The objectives of this study were to understand the characteristics of youth (aged 12-24 years) dying of accidental acute toxicity in Canada and examine the substances contributing to and circumstances surrounding youth ATDs.

Concurrent discrimination learning in Parkinson's disease.

Studies of neuropsychological patients and experimental animals have demonstrated that the striatum plays a role in implicit habit learning. Here, we examined the performance of patients with Parkinson's disease (PD) on a concurrent discrimination task that can be learned implicitly by neurologically intact individuals. Participants viewed a pair of shapes on each trial and, under a timed deadline, guessed which one concealed a smiling face.

Visual feature learning in artificial grammar classification.

The Artificial Grammar Learning task has been used extensively to assess individuals' implicit learning capabilities. Previous work suggests that participants implicitly acquire rule-based knowledge as well as exemplar-specific knowledge in this task. This study investigated whether exemplar-specific knowledge acquired in this task is based on the visual features of the exemplars.

An event-related fMRI study of artificial grammar learning in a balanced chunk strength design.

Artificial grammar learning (Reber, 1967) is a form of implicit learning in which cognitive, rather than motor, implicit learning has been found. After viewing a series of letter strings formed according to a finite state rule system, people are able to classify new letter strings as to whether or not they are formed according to these grammatical rules despite little conscious insight into the rule structure. Previous research has shown that these classification judgments are based on knowledge of abstract rules as well as superficial similarity ("chunk strength") to training strings.