The Scientist-Practitioner Model: Now More Than Ever

The scientist-practitioner model has been fundamental to the field of professional psychology for over 50 years. Although other training models have been offered in an attempt to improve training or meet other needs, we view many of the changes suggested by these models as consistent with the original intent of scientist-practitioner training. We argue that the reciprocal effects of science and practice within this model, if appropriately integrated, remain an excellent fit for integrating science and practice and enhancing the quality of both the practice and science of psychology. We address some of the problems with how the model has been implemented and offer recommendations for ways to enhance science and practice integration. Finally, we describe some of the mechanisms we have used to put these principles into practice in our counseling psychology training program.     

Central ghrelin increases anxiety in the Open Field test and impairs retention memory in a passive avoidance task in neonatal chicks

Ghrelin (Grh) is an endogenous ligand for the growth hormone secretagogue receptor. Although Ghr stimulates feeding in rats, it inhibits feeding in neonatal chicks. However, little is known about other central behavioral effects of Ghr. Therefore, we investigated the Ghr effects, injected intracerebroventricularly, on anxiety and memory retention of neonatal chicks in an Open Field test and in a one-trial passive avoidance task, respectively. In the Open Field test, the administration of Ghr in a dose-dependent manner increased the latency to ambulate but decreased ambulation activity, indicating an anxiogenic effect. Furthermore, chicks trained on a passive avoidance task and injected with a dose of 30 pmol of Ghr immediately after training showed an impairment of memory retention. However, there were no significant effects on the number of pecks during the pretraining, training, retention and discrimination. In addition, different doses of Ghr produced an inhibition in food intake at different times after injection. Our results indicate that Ghr induces anxiogenesis in chicks. Moreover, we have shown for the first time that Ghr can decrease memory retention in a non-mammalian species, suggesting that Ghr may play an important role in the processes of memory retention in birds.     

Tactile sensitivity in Asperger syndrome

People with autism and Asperger syndrome are anecdotally said to be hypersensitive to touch. In two experiments, we measured tactile thresholds and suprathreshold tactile sensitivity in a group of adults with Asperger syndrome. In the first experiment, tactile perceptual thresholds were measured. Two frequencies of vibrotactile stimulation were used: 30 and 200 Hz. The results demonstrated significantly lower tactile perceptual thresholds in the Asperger group at 200 Hz but not at 30 Hz, thus confirming tactile hypersensitivity but only for one class of stimulus. A second experiment investigated whether self-produced movement affected the perception of touch in a group of adults with Asperger syndrome. A suprathreshold tactile stimulus was produced either by the participant (self-produced condition) or by the experimenter (externally produced condition) and participants were asked to rate the perception of the tactile stimulation. The results demonstrated that, while both Asperger and control groups rated self-produced touch as less tickly than external touch, the Asperger group rated both types of tactile stimulus as significantly more tickly and intense than did the control group. This experiment confirms the finding of tactile hypersensitivity, but shows that the perceptual consequences of self-produced touch are attenuated in the normal way in people with Asperger syndrome. An abnormality in this process cannot therefore account for their tactile hypersensitivity.     

How do respondents construe ambiguous response formats of affect items?

Ambiguous response formats predict correlations from -.467 to -1 between opposite items, depending on whether the respondent's interpretation of the format is unipolar or bipolar. The authors present a procedure to investigate the proper interpretation in each case. It consists of applying nonparametric and parametric item response theory models (the Mokken and the graded response models) to pairs of opposite items in order to find the locations of the response options along the latent scale and, therefore, identify the response format construction. The authors tested this procedure on 4 samples (Ns=142-1,150) and 2 item pairs ("relaxed"-"tense" and "optimistic"-"pessimistic"). The results revealed that respondents constructed the formats as bipolar and supported the bipolarity of the item pairs.     

Response perseveration in psychopaths: Interpersonal/affective or social deviance traits?

In order to clarify the role of the two broad components of psychopathy (interpersonal/affective and social deviance; R. D. Hare, 2003) in explaining maladaptive response perseveration in psychopaths, as well as the role of reflection after punished responses in this deficit, the authors administered a card perseveration task to 47 Spanish male inmates assessed using the Hare Psychopathy Checklist-Revised (PCL-R; R. D. Hare, 1991). Hierarchical regressions showed that psychopaths' maladaptive perseveration (more cards played and less money earned) was uniquely predicted by the social deviance features of psychopathy (PCL-R Factor 2)--particularly by its impulsive and irresponsible lifestyle facet (PCL-R Facet 3)--and not by its interpersonal/affective features (PCL-R Factor 1). Moreover, perseveration was related to a lack of reflection both after punishment and after reward feedback. The authors' results, in conjunction with previous evidence indicating perseverative deficits in several impulse control disorders, suggest that response perseveration may not be specific to psychopathy but rather is associated more generally with the externalizing dimension of psychopathology.     

Evaluation of communicative and linguistic development using the Spanish version of the MacArthur-Bates inventories

The MacArthur-Bates Inventories are a valid and reliable method for assessing communicative and linguistic skills in infants (8-15 months) and young children (16-30 months), and have been adapted to many languages. This paper presents their adaptation to Spanish. Structure, innovations included in the Spanish version, and the standardisation process are described, and some results obtained from the analysis of a sample of 1150 children are presented. The advantages and limitations of the use of parental report inventories are highlighted. For children before three years of age, there are very few assessment tools of language and communicative development with sufficient guarantees produced and edited in Spain. The Spanish version of the MacArthur-Bates Inventories represents an important contribution for early identification of language delays or disorders, and for follow-up of these cases.     

Effect of incentives on retention in an outpatient treatment for cocaine addicts

The high drop-out rate in treatment programs is one of the most important problems in the area of drug addictions. This study evaluated the effect of the use of incentives on retention in an outpatient program for cocaine addicts. The effect of individual variables on program drop-out was also analysed. Participants were 66 subjects who were randomly assigned to one of three treatment groups: standard treatment, treatment with incentives I, and treatment with incentives II. The patients of these two groups received incentives contingent on cocaine abstinence with two different magnitudes. Retention rate at six months was 35% in the standard treatment, 78.6% in the treatment with incentives I, and 53.3% in the treatment with incentives II. The global prognostic capacity of the individual variables (sociodemographic, history and consumption pattern, psychopathological variables, and EuropASI scores) was 85.7%, with the psychopathological variables being more closely related to retention. These results suggest that the use of incentives may be an effective strategy to improve retention in outpatient treatments for cocaine addiction.