Effects of antipsychotic treatment on cognition in healthy subjects

Abstract

Cognitive impairments can be observed in the majority of diseases with disturbed dopamine transmission. They are considered as core symptoms of schizophrenia, a disorder in which they appear to be particularly pronounced. Their neurobiological background is not yet sufficiently investigated, but dopaminergic systems are believed to play a crucial role. The aim of this single-blind, randomised, placebo-controlled study was to examine the effects of subchronic antidopaminergic treatment on cognitive functions in healthy subjects. In total, 72 healthy volunteers, randomised into four groups, received one antidopaminergic substance (aripiprazole, haloperidol or reserpine) or placebo, respectively, for 7 days. A comprehensive neurocognitive assessment was conducted at baseline, 24 h after the last medication intake and 7 days later. In the Digit Symbol Substitution Test a distinct, statistically significant improvement was measured in the second session in the placebo but not in the medication group. A significant group*time interaction for reaction times in three subtests of the Test battery for Attentional Performance (TAP) was also found. Our findings indicate that modulation of dopaminergic systems affects primarily speed of information processing, attention and learning. Absence of effects on other functions, differing from previous reports, may be an expression of a sufficient counter-regulation.

Reward Dependent Invigoration Relates to Theta Oscillations and Is Predicted by Dopaminergic Midbrain Integrity in Healthy Elderly

“…More precisely, phasic dopamine transmission in response to a reward-predicting cue results in faster RTs (Satoh et al, 2003; Ko and Wanat, 2016), probably via innervating the NAcc (McGinty et al, 2013), which might serve as hub between reward related limbic signals and motor control circuits (Groenewegen et al, 1996). Therefore, movement initiation relies on a healthy dopaminergic system and, consequently, slower RTs have been shown in patients with Parkinson disease, who suffer from a massive loss of dopamine neurons (Mazzoni et al, 2007), during pharmacologically induced dopamine depletion in rats (Cole and Robbins, 1989), as well as in humans after D2 receptor blockage by haloperidol (Saeedi et al, 2006; Veselinović et al, 2013). …”

A Systematic Review of Cognitive Function in First-Episode Psychosis, Including a Discussion on Childhood Trauma, Stress, and Inflammation

“…As processing speed is important for the performance of higher cognitive operations, such as executive functions and memory, it has been suggested that impaired processing speed underlies the abnormalities in these areas (42). On the other hand, to complicate this further, a reduction of processing speed has also been found associated with antipsychotic medication (43). …”

Impact of chronic hyponatremia on neurocognitive and neuromuscular function

“…Intactness of the functions of attention as prerequisite for effective behaviour in everyday life was assessed using the standardised computer test system “Test of Attentional Performance (TAP) 2.1” . The TAP has been developed in 1994 by Zimmermann & Fimm as an assessment of attention deficits in adults, and has since been validated and used as a reliable tool for attentional impairment in different trials . Within this procedure, simple reaction paradigms were chosen, in which participants had to react selectively to well discriminable, non verbal visual and acoustic stimuli by a simple motoric reaction (a simple keypress).…”