Two experiments were conducted to examine whether the resistance to extinction obtained in evaluative conditioning (EC) studies implies that EC is a qualitatively distinct form of classical conditioning (Baeyens, Eelen, & Crombez, 1995 Baeyens, F , Eelen, P and Crombez, G . (1995a). Pavlovian associations are forever: On classical conditioning and extinction. Journal of Psychophysiology, 9: 127–141. a) or whether it is the result of an nonassociative artefact ( Field & Davey, 1997 Field, AP and Davey, GCL . (1997). Conceptual conditioning: Evidence for an artifactual account of evaluative learning. Learning and Motivation, 25: 446–464. , 1998 Field, AP and Davey, GCL . (1998). Evaluative conditioning: Arti‐fact or ‐fiction?‐ A reply to Baeyens, De Houwer, Vansteenwegen, and Eelen (1998). Learning and Motivation, 29: 475–491. , 1999 Field, AP and Davey, GCL . (1999). Reevaluating evaluative conditioning: A nonassociative explanation of conditioning effects in the visual evaluative conditioning paradigm. Journal of Experimental Psychology: Animal Behavior Processes, 25: 211–224. ). Both experiments included between‐subjects control groups in addition to standard within‐subjects control conditions. In Experiment 1, only verbal ratings were measured in order to evaluate the effect of postacquisition CS‐only exposures on EC whereas in Experiment 2, verbal ratings and postextinction priming effects were measured. The results showed that the EC effects are demonstrable in a between‐subjects design and that the extinction procedure did not have any influence on the acquired evaluative value of CSs regardless of whether the verbal ratings or the priming effects were used as dependent variables. The present results provide evidence that EC is resistant to extinction and suggest an interpretation of EC as a qualitatively distinct form of associative learning.

Traditional diagnostic scales are based on a number of symptoms to evaluate and classify mental diseases. In many cases, this process becomes subjective, since the patient must calibrate the magnitude of his/her symptoms and therefore the severity of his/her disorder. A completely different approach is based on the study of the more vulnerable traits of cognitive disorders. In this regard, animal models of mental illness could be a useful tool to characterise indicators of possible cognitive dysfunctions in humans. Specifically, several cognitive disorders such as schizophrenia involve a dysfunction in the mesocorticolimbic dopaminergic system during development. These variations in dopamine levels or dopamine receptor sensibility correlate with many behavioural disturbances. These behaviours may be included in a specific phenotype and may be analysed under controlled conditions in the laboratory. The present study provides an introductory overview of different quantitative traits that could be used as a possible risk indicator for different mental disorders, helping to define a specific endophenotype. Specifically, we examine different experimental procedures to measure impaired response in attention linked to sensorimotor gating as a possible personality trait involved in maladaptive behaviours.

An attention disturbance is a problem that affects many school-aged children. The assessment in children is usually report-based, and as a result, controversy surrounds the diagnosis. To solve this issue, the aim of this study was to develop a new tool to detect possible attention-related problems and impulsive behavior in 4- and 5-year-old children. This tool was developed as an Android app and could be used to provide an early indicator of possible future development problems. A sample of 103 children (48 girls and 55 boys) was randomly selected from primary schools and assessed by Pinky-Piggy, a videogame application based on a classical paradigm in experimental psychology. Data from this app were compared with a Child Neuropsychological Maturity Questionnaire. The subjects displayed different patterns of response to play a very simple game called Pinky-Piggy. The application discriminated between high-responders and low responders. The results showed a relationship between these two profiles and the levels of attention and neurodevelopment in each group. The tool could identify different types of profiles and demonstrated its potential to evaluate endophenotypes to predict attentional problems related to impulsive behavior. Additionally, it required less time and fewer tests to identify possible at-risk populations, thus assisting in clinical diagnosis.

The utilization of methylphenidate (MPH) is experiencing a notable surge within the adult population. This growth can be attributed to two key factors: its recreational and cognitive enhancement purposes, as well as the rising prevalence of ADHD diagnoses within this population. This study examined acute and chronic oral MPH effects on attention in male and female Wistar rats. To this end, we used a prepulse inhibition (PPI) task, which is widely used to assess psychoactive drug effects in both humans and rodents. This task allowed us to evaluate changes in attention by analyzing sensorimotor gating associated with stimulus selection process. Animals were administered a clinically relevant dose of MPH (5 mg/kg) daily for seven days. The estrous cycle phases of the female rats were measured during behavioural sessions. The PPI task was conducted 20 minutes after drug administration on day 1 (acute), day 7 (chronic), and 48 hours post-treatment. Results indicated that both acute and chronic MPH treatment impaired PPI expression in male rats, but not in female rats, regardless of their estrous cycle phase. Furthermore, a differential effect of chronic MPH treatment on the PPI task was found in male rats. Specifically, on the seventh treatment day, the PPI effect was observed when animals undertook the PPI task for the first time but was impaired in those animals in which the initial PPI session occurred under the acute influence of the drug (day 1). These findings suggest that the impact of MPH on sensorimotor gating responses may vary based on sex and task experience, possibly leading to state-dependent effects in healthy individuals.