A methodological approach to manipulation of hunger and thirst drive stimuli in the rat

The hunger and thirst drives of rats were equated using a titration procedure in a modified T-maze with food as the reinforcer on the left and water on the right. The conditions (amount) rather than schedules (hours) of maintenance were varied from day to day during a 9-day cycle which was then replicated. The results showed that condition manipulations produce reliable and approximately linear functions for individual Ss on the following response measures: percent water choices, median latencies, and body weight. Results were discussed in terms of the animals responding to the drive stimuli and also in terms of some of the methodological problems that this procedure solved. Finally, it was suggested that the construct drive as defined by conditions of maintenance might possess more utility as an experimental variable.     

LONG-TERM EFFECTS OF OPPOSITIONAL CHILD TREATMENT WITH MOTHERS AS THERAPISTS AND THERAPIST TRAINERS

The follow-up data reported represent a long-term (3 to 9 years out of treatment) evaluation of 40 children who were clients of the Regional Intervention Program (RIP) from 1969 to 1978. As 3-, 4-, and 5-year olds, these youngsters exhibited severe and prolonged tantrums, continual opposition to adults' requests and commands, and physical aggression toward parents. Each child and mother participated in a standardized intervention package modeled after Wahler's Opposition Child Treatment. Results from school and home-based follow-up showed that: (a) commands, demands, or requests made by parents were likely to be followed by former clients' compliance; (b) former clients' social interactions in the home were overwhelmingly positive and their nonsocial behavior was by and large appropriate; (c) parent behavior in the home was consistent with the child management skills taught many years ago; (d) there were no differences between the compliant, on-task, social interaction and appropriate/inappropriate nonsocial behaviors of former clients and randomly selected class peers; (e) there were no differences in teachers' commands, negative feedback, positive social reinforcement, and repeated commands that were directed toward either former clients or randomly selected class peers; (f) both teachers' and parents' rating of former clients on the modified Walker Problem Behavior Checklist were highly correlated; (g) there were no differences in teachers' rating of former clients and class peers; and (h) of all the studied demographic variables, only age that treatment began and family intactness were related to current levels of behavior.     

TRAINING FUNCTIONAL EXPRESSIVE LANGUAGE: THE ACQUISITION AND GENERALIZATION OF FIVE-ELEMENT SYNTACTIC RESPONSES1

A single-subject multiple-baseline design using within- and across-subject replication was employed to study the acquisition of expanded “agent-action-object” sentences and the spontaneous generation of this form in the natural environment. Three young language-delayed subjects were trained to describe various agent-action-object relationships with a five-element syntactical form. The language training strategy was a synthesis of the developmental-psycholinguistic and behavioral models. Dynamic interactions between familiar persons and objects were the stimulus events that the children mapped. A five-element syntactical form, previously absent from the children's language repertoires, was trained during individual sessions. Concurrent with baseline, training, and followup, each subject's language was monitored in another setting, the classroom during free play. After onset of training, the core elements of the complex syntactic form were spontaneously emitted by the child in its natural environment. The free-play data reflect individual differences in the emergence and frequency of each child's spontaneous use of the agent-action-object form. The acquisition and maintenance of the specific lexicon and syntax trained were tested by posttraining probes and responses to videotape presentations. These probes revealed generalization and maintenance of both the lexical and syntactical forms acquired in treatment. The main purpose of any language-training procedure should be to provide language that is functional for the child in the natural environment. This study, which documented the spontaneous usage of the core agent-action-object syntactical form in the natural environment, effectively trained a functional syntactical rule.     

The frequency and significance of additional self-reported psychiatric diagnoses in children with attention deficit disorder

The frequency of additional self-reported diagnoses in a large, heterogeneous sample of attention defiict disorder (ADD) children (N=182)was determined using the Diagnostic Interview for Children and Adolescents (DICA). Over half the children had additional DICA diagnoses, with oppositional disorder and anxiety/mood disorders the most frequent. ADD boys with internalizing-type diagnoses had lower verbal IQs and arithmetic scores and performed more poorly on attention tasks than those without; parents also rated them more adversely. Those with externalizing- type diagnoses were rated as more aggressive by teachers and had sociopathic, thrill- seeking profiles on paper-pencil self-ratings. Over 40% of the children were dyslexic or slow learners but they had no higher rate of DICA diagnoses than those who read adequately.This research was supported by NIMH grant R01-MH39189 and by the Marie Wilson Howells Fund. The authors are grateful to the Chid Study Center staff who assisted in recruiting and evaluating subjects and to the Behavioral Laboratory team members who collected and analyzed the data.     

Auditory stimulus intensity gradients and response to methylphenidate in ADD children

Using an auditory stimulus intensity paradigm, we obtained both event related potentials (ERPs) and press and release reaction times (RT) from a large sample of children with Attention Deficit Disorder (ADD). The ERP gradients to three tone intensities were used to classify the children as augmenters (steep gradients), moderates, or reducers (shallow or negative gradients). The RT data were used to classify the children as strong or sensitive, following neo-Pavlovian guidelines. The children were then cross-classified on these two dimensions and compared on cognitive, behavioral, and performance measures. The groups were also compared in response to two dosage levels of methylphenidate. Based on prior studies, we hypothesized that: 1. ERP augmenters would respond as well to the low as high dose but that reducers would respond better to high than low dose; and II. sensitive types (RT measure) would do better on the higher dose and strong types on the low dose. The first hypothesis was confirmed on a performance task but not on behavioral ratings. At the lower dose, augmenters improved most and reducers least on a 10-minute coding task presumed to require sustained attention. There was no support for the second hypothesis either in ratings or performance. The ERP augmentation measure was significantly related to teacher rated attentiveness; i.e., reducers and moderates were rated more adversely. The RT sensitivity measure tended to be related to achievement; i.e., strong types had lower reading and spelling scores. The ERP and RT sensitivity measures were not significantly correlated.     

Conditioned task-set competition: Neural mechanisms of emotional interference in depression

Depression has been associated with increased response times at the incongruent-, neutral-, and negative-word trials of the classical and emotional Stroop tasks (Epp et al., Clinical Psychology Review, 32, 316–328, 2012). Response-time slowdown effects at incongruent- and negative-word trials of the Stroop tasks were reported to correlate with depressive severity, indicating strong relevance of the effects to the symptomatology. This study proposes a novel integrative computational model of neural mechanisms of both the classical and emotional Stroop effects, drawing on the previous prominent theoretical explanations of performance at the classical Stroop task (Cohen, Dunbar, & McClelland, Psychological Review, 97, 332–361, 1990; Herd, Banich, & O’Reilly, Journal of Cognitive Neuroscience, 18, 22–32, 2006), and in addition suggesting that negative emotional words represent conditioned stimuli for future negative outcomes. The model is shown to explain the classical Stroop effect and the slow (between-trial) emotional Stroop effect with biologically plausible mechanisms, providing an advantage over the previous theoretical accounts (Matthews & Harley, Cognition & Emotion, 10, 561–600, 1996; Wyble, Sharma, & Bowman, Cognition & Emotion, 22, 1019–1051, 2008). Simulation results suggested a candidate mechanism responsible for the pattern of depressive performance at the classical and the emotional Stroop tasks. Hyperactivity of the amygdala, together with increased inhibitory influence of the amygdala over dopaminergic neurotransmission, could be at the origin of the performance deficits.     

Effects of Aging on Functional Connectivity of the Amygdala for Subsequent Memory of Negative Pictures: A Network Analysis of Functional Magnetic Resonance Imaging Data

ABSTRACT— Aging is associated with preserved enhancement of emotional memory, as well as with age-related reductions in memory for negative stimuli, but the neural networks underlying such alterations are not clear. We used a subsequent-memory paradigm to identify brain activity predicting enhanced emotional memory in young and older adults. Activity in the amygdala predicted enhanced emotional memory, with subsequent-memory activity greater for negative stimuli than for neutral stimuli, across age groups, a finding consistent with an overall enhancement of emotional memory. However, older adults recruited greater activity in anterior regions and less activity in posterior regions in general for negative stimuli that were subsequently remembered. Functional connectivity of the amygdala with the rest of the brain was consistent with age-related reductions in memory for negative stimuli: Older adults showed decreased functional connectivity between the amygdala and the hippocampus, but increased functional connectivity between the amygdala and dorsolateral prefrontal cortices. These findings suggest that age-related differences in the enhancement of emotional memory might reflect decreased connectivity between the amygdala and typical subsequent-memory regions, as well as the engagement of regulatory processes that inhibit emotional responses.