Children with developmental coordination disorder (DCD) and their ability to disengage ongoing attentional focus: more on inhibitory function

Children with developmental coordination disorder (DCD), along with their Control counterparts, completed two endogenous, spatial precue tasks. When the precue arrow was informative (.80) with respect to target location, the spatial precue effect results demonstrated that children with DCD take significantly longer than Control individuals to volitionally disengage (inhibit) attention from an endogenously cued location (i.e., a disengagement inhibition deficit). When the precue was uninformative (.25), we found, contrary to a common assumption, that the precue arrow automatically moved attention in the direction of the arrow, and, in addition, that DCD children may also be less able to inhibit the precued-induced urge to move attention (i.e., an initiation inhibition deficit). This type of inhibitory difficulty was also indicated for manual response inclinations produced on catch trials. Overall, DCD children appeared to have an elevated difficulty suppressing the initiation of incorrect, stimulus-provoked movement urges, be they manual or attention in nature.     

Serial dependence in the estimation of a car's arrival time

Serial dependence of a car's arrival time. We have studied the sequential structure of data in the arrival- time estimations. Forty participants estimated the arrival-time of a vehicle under two experimental conditions: real car and video-image. Various time series regression models were fit to our data, and residuals autocorrelations were computed. For each serial-dependence model, data were fit to three functions, namely, power, logarithmic, and linear. In both experimental conditions, the response magnitude (R) on a given trial in t was a function of the stimulus intensity (S) in such a trial (t) and of the S and R on t-1 and t-2. Assimilation effect to the previous responses and contrast effect to the previous stimuli has been found.     

Capuchin monkeys, inequity aversion, and the frustration effect

Each of 4 female capuchin monkeys ("model") was paired with another female capuchin ("witness") in an adjacent cage. In Phases 1 and 3, a model could remove a grape from the experimenter's hand while the witness watched. The witness was then offered a slice of cucumber, a less preferred food. Trials alternated between subjects 50 times, defining a session. In Phases 2 and 4, both were offered cucumber. Witness rejections of cucumber were infrequent and were not dependent on whether models received grape or cucumber. When models were offered cucumber, they rejected it at higher rates than did witnesses. These results fail to support findings of Brosnan and de Waal. An account based on the frustration effect accommodates these results and those of Brosnan and de Waal.     

Comparing speed estimations from a moving vehicle in different traffic scenarios: absence versus presence of traffic flow

The aim of this research was to study the performance in a speed estimation task of a passenger travelling in a real car in different scenarios: a closed track used in previous experimental studies was compared with interurban traffic environment involving a secondary road and a highway. At the same time, the effect of sex and driving experience on speed estimation was analyzed. Thirty-six participants (18 male and 18 female, half of each group being drivers and half non-drivers) estimated the speed of the car in which they travelled as passengers. The actual speed values varied in the range of 40-100 km/h for the secondary road, 70-120 km/h for the highway condition, and 40-120 km/h for the track. The results obtained for the track in previous studies (Recarte and Nunes, 1996; Recarte, Conchillo, and Nunes, 2004, 2005) were replicated in the same condition and were also verified for the secondary road scenario. However, a different pattern of errors was found for the highway. From the viewpoint of psychophysics, the participants were more accurate on the without-traffic track than in real traffic conditions, considered as a whole. The differences found between road and highway are discussed. No effect was found for between- subject variables, sex, and driving experience.     

Crossmodal integration of emotional information from face and voice in the infant brain

We examined 7-month-old infants' processing of emotionally congruent and incongruent face-voice pairs using ERP measures. Infants watched facial expressions (happy or angry) and, after a delay of 400 ms, heard a word spoken with a prosody that was either emotionally congruent or incongruent with the face being presented. The ERP data revealed that the amplitude of a negative component and a subsequent positive component in infants' ERPs varied as a function of crossmodal emotional congruity. An emotionally incongruent prosody elicited a larger negative component in infants' ERPs than did an emotionally congruent prosody. Conversely, the amplitude of infants' positive component was larger to emotionally congruent than to incongruent prosody. Previous work has shown that an attenuation of the negative component and an enhancement of the later positive component in infants' ERPs reflect the recognition of an item. Thus, the current findings suggest that 7-month-olds integrate emotional information across modalities and recognize common affect in the face and voice.     

Aging and response inhibition: Normative data for the Victoria Stroop Test

Increased difficulty with response inhibition occurs with age, although there is some controversy as to whether increased interference on Stroop tasks reflects difficulties with response inhibition or simply reflects generalized cognitive slowing. The Victoria Stroop Test (VST) is a brief, easily administered, psychometrically sound version of Stroop's original task. Performance on the VST by adults across a wide age span was examined to determine the association between age and various measures of interference. In addition, normative data for the VST were calculated. Participants were 272 healthy, community-dwelling adults age 18 to 94. Age and speed were negatively correlated on all trials of the VST. Importantly, however, interference scores that were corrected for baseline slowing remained highly correlated with age. Similarly, age and error scores on the interference trial were positively correlated, indicating decreased accuracy with age. These findings suggest that increased interference on Stroop tasks with age is not accounted for by simple cognitive slowing and more likely reflects other cognitive changes, such as decreased response inhibition. The VST has a number of administrative and psychometric strengths, and the provision of normative data should enhance its potential for clinical and research applications.     

Development of affective decision making for self and other: evidence for the integration of first- and third-person perspectives

The role of perspective taking in affective decision making was studied in children at two ages (3 and 4 years) using a delay-of-gratification paradigm in which children chose between an immediate reward of lower value and a delayed reward of higher value. Half the children chose for themselves (self condition), and half chose for the experimenter (other condition). Three-year-olds chose delayed rewards in the other condition but made impulsive choices in the self condition. Compared with 3-year-olds, 4-year-olds performed better in the self condition and worse in the other condition. Results suggest that 3-year-olds took either a subjective, first-person perspective (for self) or an objective, third-person perspective (for other). Four-year-olds integrated these perspectives, considering a third-person perspective in the self condition and the experimenter's subjective perspective in the other condition (i.e., her desire for immediate gratification). This integration allowed reason to be tempered by emotion, and vice versa.     

Less is more: executive function and symbolic representation in preschool children

Executive function is recognized as a critical component of children's cognitive and social development. In two studies, a measure of executive function that had been used in research with chimpanzees was adapted for preschoolers. On this task, called Less Is More, children must point to a smaller reward (two candies) to receive a larger reward (five candies). In Study 1 (N= 101), performance was significantly related to age (3 vs. 4), verbal ability, and established measures of executive function. In Study 2 (N= 128), symbolic representations substituted for real candies in this task. Three-year-olds' performance improved significantly as a function of symbolic distancing. This research has implications for the role of symbol systems in the development of executive control over thought and action.