ABSTRACT
BACKGROUND: Inhibitory control, a key modulatory component of cognition guiding strategy and behaviour, can be affected by diverse contingencies. We explore here the effect of expectation of reward over behavioural adjustment in a Stop Signal Task modulated by reward. We hypothesize that cognitive control is modulated by different expectation of the reward. METHODS: Participants were allocated to two groups differing in their degree of knowledge in what to expect from rewards. Expected Specific Reward participants (N = 21) were informed of the different monetary feedbacks they would receive after each successful inhibition. Unexpected Reward participants (N = 24) were only told that they would receive monetary reward after correct inhibitory trials, but not the amounts or differences. RESULTS: Our results confirmed previous observations demonstrating a "kick-start effect" where a high reward feedback at the beginning of the task increases response inhibition. The Expected Specific Reward condition seems also to improve inhibitory control -as measured by the stop signal reaction time (SSRT)-, compared to the Unexpected Reward group. CONCLUSIONS: Knowledge of reward magnitudes seems to play a role in cognitive control irrespective of feedback magnitude. The manipulation of reward expectation appears to trigger different strategies for cognitive control, inducing a bottom-up effect of external cues, or a top-down effect given by the anticipation of incoming rewards. This is an early exploration to unearth possible higher order modulators - expectation and motivation- of cognitive control. This approach aims to gain insight into diverse psychopathological conditions related to impulsivity and altered reward systems such as Attention Deficit Hyperactive Disorder (ADHD), personality disorders, substance abuse, pathological gambling and cognitive aspects of Parkinson Disease.
Subject(s)
Executive Function , Motivation , Reward , Adult , Cognition , Cues , Female , Humans , Inhibition, Psychological , Male , Reaction Time , Young AdultABSTRACT
OBJECTIVE: To investigate possible relationships between symptoms of ADHD and of learning disorder (LD) in a population geographically, culturally, and linguistically distinct from previous studies. METHOD: The authors evaluated a cross section of 834 Colombian schoolchildren for childhood neurological pathologies on the basis of a medical examination and performance with reference to the Diagnostic and Statistical Manual (4th ed.) attention checklist, the General and Differential Aptitudes Battery, and the Visual-Motor Integration (VMI) test. RESULTS: Of the total sample, 382 were classified as "ADHD only," 54 as "LD only," and 75 as "ADHD + LD." A total of 459 had low VMI scores. ADHD, LD, and low VMI were significantly interrelated. Among the children with ADHD, the attention deficit subtype tended to have more learning problems than the hyperactive subtype, who showed no major deficiencies in their learning ability. CONCLUSIONS: This study provides additional evidence demonstrating a relationship between LD and ADHD, particularly with respect to verbal reasoning, visual-auditory memory, and VMI.
Subject(s)
Attention Deficit Disorder with Hyperactivity/diagnosis , Learning Disabilities/diagnosis , Attention , Attention Deficit Disorder with Hyperactivity/complications , Child , Child, Preschool , Colombia , Cross-Sectional Studies , Female , Humans , Learning Disabilities/complications , Male , Memory , Neuropsychological TestsABSTRACT
El síndrome de secuencia acinesia/hipocinesia fetal es un trastorno genético raro, descrito en 1974, por Pena y Shokeir, en dos hermanas que murieron al nacer con camptodactilia, pie equino, anquilosis de las rodillas y las caderas e hipoplasia pulmonar. Este síndrome afecta, aproximadamente a uno de cada 12.000 recién nacidos, y en la bibliografía médica se han reportado unos sesenta casos, los cuales en su mayoría son esporádicos. Además, buena parte de los casos familiares parece tener una herencia autosómica recesiva (25% de riesgo de recurrencia).Aunque la etiología es desconocida, en1983 Moessinger propuso que una disminución de los movimientos fetales en el útero puede llevar a un cuadro similar y propuso llamarlo secuencia de deformación por acinesia fetal
Fetal akinesia/hypokinesia sequence syndrome is a rare genetic disorder described in 1974 by Pena and Shokeir in two sisters who died at birth with camptodactyly, clubfoot, ankylosis of the knees and hips, and pulmonary hypoplasia. This syndrome affects approximately one in 12,000 newborns, and about sixty cases have been reported in the medical literature, most of which are sporadic. Although the etiology is unknown, in 1983 Moessinger proposed that a decrease in fetal movements in utero can lead to a similar picture and proposed to call it fetal akinesia deformation sequence
