OBJECTIVES To compare within the same individuals two typically prescribed doses of hydrocodone/acetaminophen and oxycodone/acetaminophen products for their subjective, psychomotor, and physiological effects in healthy volunteers. DESIGN A randomized, placebo-controlled, double-blind, crossover, six-session clinical laboratory study, enrolling 16 healthy participants (27.2 +/- 4.4 years of ag...

Background: Psychomotor retardation is a prominent clinical feature of major depression. While several studies investigated these deficits, differences between internally and externally triggered response selection and initiation are less well understood. In the current study, we delineate internally vs. externally driven response selection and initiation in depression and their relation to bas...

Objective The extent to which increasing age is associated with impairment in cognitive function, termed cognitive aging, may have been overestimated in prior studies. The inclusion of individuals with severe or uncontrolled systemic medical illness or prodromal neurodegenerative disease in normal aging samples is likely to bias estimates toward lower cognitive performance and inflate estimates...

The role of illicit drugs on driving, and particularly of cannabis and driving, is the object of increasing awareness. While there is increasing evidence of their effect on psychomotor performance and increased risk of involvement in traffic accidents, limited information is available concerning factors that can predict the likelihood of driving under the influence of cannabis. The present stud...

Cold exposure accelerates the firing frequency of norepinephrine (NE) neurons, enhancing NE release and leading to NE depletion in specific regions of the brain. The accelerated firing activates the enzyme tyrosine-hydroxylase, making it more tyrosine sensitive. The reduction of brain NE is accompanied by a behavioral depression on the open field test. Two experiments were performed on adult ma...

STUDY OBJECTIVES To assess the effect of 200 mg of modafinil compared to placebo on alertness, neurobehavioral performance, and executive function during 4 consecutive simulated night shifts. DESIGN Double-blind, randomized, parallel groups. SETTING Sleep research facility. PARTICIPANTS 32 male and female volunteers between the ages of 18 and 55 years. INTERVENTIONS 200 mg of modafinil ...

This study reports the executive function profile in people with schizophrenia, with a simultaneous comparison of chronicity and of those with predominately disorganization versus psychomotor poverty symptoms. The patients were split into one set defined according to symptoms (29 with disorganization, 29 with negative symptoms) and the other representing chronicity (22 first-episode, 35 chronic...

Stimulation of dopamine D1 receptors has profound effects on addictive behavior, movement control, and working memory. Many of these functions depend on dopaminergic systems in the striatum and D1-D2 dopamine receptor synergies have been implicated as well. We show here that deletion of the D1 dopamine receptor produces a neural phenotype in which amphetamine and cocaine, two addictive psychomo...