Effect of a stimulus intervening between CS and US in autoshaping.

Five experiments explored the effect of placing a stimulus between the termination of a key light (CS) and the onset of a food (UCS) with female Carneaux pigeons in an autoshaping preparation. Whether that stimulus was itself a key light evoking pecking or an auditory event failing to evoke pecking, it facilitated performance to the CS. The use of a within-Ss design made differential conditioning of background cues and stimulus generalization unlikely accounts. Exp III found that extinction of the intervening stimulus did not remove the facilitative effect. Exp IV found that pairing the CS with food and the intervening stimulus did not produce the effect unless both occurred on the same trial. Together, these experiments rule out an account in terms of 2nd-order conditioning of the CS by the intervening stimulus. Exp V used an intervening stimulus in a 2nd-order conditioning design to demonstrate that the stimulus acted to improve the association between the CS and the reinforcer. Results document a kind of catalytic effect of the intervening stimulus on the CS-reinforcer association. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Redundant treatment of neutral and excitatory stimuli in autoshaping.

Five autoshaping experiments with pigeons exposed excitatory and neutral stimuli to treatments that made those stimuli uninformative with respect to the unconditioned stimulus (US). Experiment 1 found that adding sufficient USs in the absence of the conditioned stimulus (CS) to make it uninformative prevented conditioning of that CS but did not undermine conditioning of a previously trained CS. Experiment 2 found a similar data pattern when an excitatory or neutral B stimulus was embedded in an A+/BA+ paradigm with an excitatory A. Experiments 3–5 verified that finding when the salience of A and B or the conditioning level of B was varied. These results, which are largely unanticipated by current theories of conditioning, suggest that the consequences of making a stimulus redundant depend on its conditioning level prior to that treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of signaling intertrial unconditioned stimuli in autoshaping.

Context–UCS associations have been suggested as the mediator of the response decrement that occurs when extra UCSs are added to the intertrial intervals (ITIs) of a standard Pavlovian conditioning situation. The present autoshaping experiments were concerned with the effect of signaling those extra UCSs, since such signaling might be expected to lessen their ability to condition the context. In Exp I, 16 female Carneaux pigeons were trained in Skinner boxes before receiving pretraining with the CS to be used as the signal of the ITI UCSs. During the main training, Ss were given autoshaping with a keylight CS. Exp II used a tone CS with 31 Ss. Results show that signaling the ITI UCSs did reduce their detrimental effects in responding to the CS. To determine whether that reduction was due to an impact of signaling on the target-CS/UCS association or on performance to the target-CS, Exp III examined responding to differentially trained CSs in a common context, as well as responding to identically trained CSs in differentially trained contexts with 32 Ss. More responding occurred to the CS trained with signaled, as compared with unsignaled, ITI UCSs; further, there was more responding to that CS in the more highly valued context. Results suggest that contextual value does interact with CS–UCS learning and may also affect performance to the CS. (42 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

CS–US contiguity and CS intensity in conditioning of the rabbit's nictitating membrane response to serial compound stimuli.

Two experiments examined 48 female albino rabbits' nictitating membrane response to serial-compound stimuli consisting of 2 distinctive CSs (CSA and CSB) that were followed by a shock UCS. In Exp I, CSA was a highly salient 93-db tone, and CSB was a moderately salient flashing light. The CSA/UCS interval was 800 msec, and the CSB/UCS interval was varied across 400, 600, and 800 msec. In Exp II, the flashing light served as CSA, and CSB was either a 73-, 85-, or 93-db tone. The CSA/UCS interval remained 800 msec, and the CSB/UCS interval was fixed at 400 msec. The CSB/UCS interval and CSB intensity determined the rate of CR acquisition to the compound. Yet, CR acquisition to CSB showed impairments relative to the level of responding in single CS-control conditions. However, the impairment in CR acquisition to CSB was attenuated by increasing CSB/UCS contiguity. The impairment in acquisition to the light CSB appeared to be primarily a consequence of the tone CSA's greater salience. However, impairments in CR acquisition to CSB appeared even when CSB had the combined advantages of CS/UCS contiguity and great salience relative to CSA. Results indicate a role for CSA's temporal primacy in determining CR acquisition to the components of a serial compound and are discussed in terms of selective-attention, generalization-decrement, and information hypotheses. (45 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Extending conditioned stimuli before versus after unconditioned stimuli: Implications for real-time models of conditioning.

In four experiments using the conditioned suppression procedure with rats, we compared the effects of extending conditioned stimuli (CSs) before versus after reinforcement (called B vs. A extensions). In Experiments 1 and 2, Group 0 (no extension) received 2-min noise CS trials (3 per day in Experiment 1, 1 per day in Experiment 2) that terminated with a 1-s grid shock unconditioned stimulus (US). For Group B, the CS began 12 min before the US; for Group A, the CS began 2 min before the US but persisted for 10 min past US termination. In Experiments 3 and 4, similar trials (3 per day in Experiment 3, 1 per day in Experiment 4) included a 2-min light CS that always terminated with the US; thus the noise CS became a systematically manipulated context cue in which light-shock pairings were embedded. In Experiments 1 and 2 we found asymmetrical effects of CS extensions: B extensions weakened conditioning more than did A extensions. In Experiments 3 and 4 we found symmetrical effects: A and B extensions weakened context conditioning equally. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Bridging the gap: Transitive associations between items presented in similar temporal contexts.

In episodic memory tasks, associations are formed between items presented close together in time. The temporal context model (TCM) hypothesizes that this contiguity effect is a consequence of shared temporal context rather than temporal proximity per se. Using double-function lists of paired associates (e.g., A–B, B–C) presented in a random order, the authors examined associations between items that were not presented close together in time but that were presented in similar temporal contexts. After learning, across-pair associations fell off with distance in the list, as if subjects had integrated the pairs into a coherent memory structure. Within-pair associations (e.g., A–B) were strongly asymmetric favoring forward transitions; across-pair associations (e.g., A–C) showed no evidence of asymmetry. While this pattern of results presented a stern challenge for a heteroassociative mediated chaining model, TCM provided an excellent fit to the data. These findings suggest that contiguity effects in episodic memory do not reflect direct associations between items but rather a process of binding, encoding, and retrieval of a gradually changing representation of temporal context. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Importance of relative temporal parameters in trace autoshaping: From excitation to inhibition.

Studied the role of the relative durations of CS–UCS gap and intertrial interval (ITI) in 2 autotracing experiments. In Exp I, CS–UCS gap duration was held constant at 12 sec, and the ITI was systematically varied between 15 and 240 sec across 5 groups of 6 female White Carneaux pigeons. Conditioned excitation (CS-approach) emerged at ITIs of greater than 60 sec, and conditioned inhibition (CS-withdrawal) emerged at ITIs of less than 60 sec. In Exp II, with 50 Ss, the time between successive UCSs averaged 87 sec, and the duration of the CS–UCS gap varied from 6 to 72 sec. CS-approach was observed only in the 6-sec gap condition, and CS-withdrawal developed with gaps of 24 sec or more. Findings indicate that the relative durations of CS–UCS gap and the ITI are more important than is the absolute degree of CS–UCS contiguity in determining whether and what type of conditioning occurs on trace arrangements. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Long extension of effective CS-US interval by anesthesia between CS and US.

Conducted 3 experiments in which a total of 179 female Sprague-Dawley rats ingested a novel solution. Ss which were then anesthetized for a CS-UCS interval of approximately 9 hr. and poisoned on recovery from anesthetic showed a clear aversion to the novel solution. The same CS-UCS interval did not support any measureable aversion when Ss were awake in the interval. It is suggested that the CS-UCS interval might be extended indefinitely with this technique. Results are not consistent with a simple decay model and are quite compatible with interference or learned safety models of conditioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Professional burnout in clinical military psychologists: Recommendations before, during, and after deployment.

Clinical military psychologists (CMPs) hold one of the most difficult positions within professional psychology. Given their exposure to a variety of environmental, physical, psychosocial, and emotional stressors, professional burnout (PB) can be a serious issue for CMPs. In order to (a) protect job satisfaction, (b) increase professional confidence, (c) facilitate a long and rewarding military career, and (d) ensure competent care is provided to our clients, a two-pronged approach of CMPs taking care of themselves on the one hand, and the military providing effective assessment, prevention, and intervention, on the other hand, is needed. Such an approach to protecting the military's limited mental health resources could ultimately ensure that service members receive proper care. In this article, the authors discuss the challenges experienced by CMPs as potential contributors to PB during all three phases of the deployment cycle. Several recommendations are offered for addressing such challenges. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Temporal patterns of the rabbit's nictitating membrane response to compound and component stimuli under mixed CS–US intervals.

The acquisition of the rabbit's nictitating membrane response to a tone and light compound and to its components was examined when compound presentations were reinforced at one conditioned stimulus–unconditioned stimulus (CS–US) interval and individual component presentations were reinforced at another CS–US interval. Examination of the time course of the CRs revealed that (a) despite the mixture of CS–US intervals, conditioned response (CR) timing remained accurate, that is, CRs reached their peaks at the alternative points of US delivery; (b) the momentary magnitude of the CR to the compound was predominately an additive function of the CR magnitude to the individual components; but (c) there was modest evidence of differentiation between the compound as a unit and the individual components. The results are discussed in terms of their implications for the study of the neural substrates of temporal and sensory integration as they modulate CR acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Olfactory functioning before and after temporal lobe resection for intractable seizures.

An olfactory test battery was administered monorhinically to 21 epilepsy patients prior to and 6 mo after unilateral medial temporal lobe resection for treatment of intractable seizures. 33 matched control Ss were also tested. Presurgically, controls and patients exhibited normal sensitivity for 1-butanol. Patients performed at levels significantly below controls on tests for odor discrimination, odor memory, and odor naming. Left-resected patients did not show significant changes following surgery. Right-resected patients demonstrated significant right nostril decline. Postsurgical changes demonstrated by the right-resected group were not attributable to deficits in primary sensory function or to deficits in cognition brought on by surgery. These findings imply that right medial temporal lobe structures play a greater role in olfactory processing than do corresponding structures in the left hemisphere. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Body image in obese women before, during, and after weight loss treatment.

Body image, as measured by the Appearance Evaluation and Body Areas Satisfaction scales of the Multidimensional Body-Self Relations Questionnaire (T. F. Cash, 1994b), was assessed in 59 obese women before, during, and after 48 weeks of weight loss treatment. Before treatment, positive ratings of body image were associated with higher levels of self-esteem, lower levels of dysphoria, and fewer previous diets. After 24 weeks and a mean weight loss of 19.4 kg (SD?=?6.5), participants showed significant (p ?p ?     

Summation in autoshaping is affected by the similarity of the visual stimuli to the stimulation they replace.

Pigeons received autoshaping with 2 stimuli, A and B, presented in adjacent regions on a television screen. Conditioning with each stimulus was therefore accompanied by stimulation that was displaced from the screen whenever the other stimulus was presented. Test trials with AB revealed stronger responding if this displaced stimulation was similar to, rather than different from, A and B. For a further experiment the training just described included trials with A and B accompanied by an additional, similar, stimulus. Responding during test trials with AB was stronger if the additional trials signaled the presence rather than the absence of food. The results are explained with a configural theory of conditioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The CS–US interval and taste aversion learning: A brief look.

Temporal parameters of taste aversion learning are known to differ markedly from other learning paradigms in that acquisition occurs despite lengthy delays between exposure to conditioned (CS) and unconditioned stimulus (US). Far less consideration has been paid to very brief CS-US intervals and the possibility that this learning may also be distinguished by an ineffectiveness of close temporal contiguity between CS and US. The effectiveness of a very brief CS-US interval (10 s) was compared with that of 2 lengthier intervals (15 and 30 min). Temporal control of CS delivery (0.15% saccharin solution) into the oral cavity and US delivery (7.5 mg/kg apomorphine hydrochloride) into circulation involved infusion pumps and indwelling catheters. Using a 1-trial learning paradigm, CS-US delays of 15 and 30 min led to significant aversions whereas the 10-s CS-US interval did not, suggesting that close temporal contiguity between CS and US is neither necessary nor sufficient for conditioned taste aversion acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differences between nouns and verbs after anterior temporal lobectomy.

To test the claim that lesions of left anterior and middle temporal cortical structures specifically impair processing of nouns but not verbs, 56 left-hemisphere-language-dominant patients who had undergone anterior temporal lobectomy (ATL) completed tasks assessing confrontation naming of pictured objects and actions, generation of synonyms for nouns and verbs, and semantic lexical judgments about nouns and verbs. Compared with right ATL patients left ATL patients were impaired across different tasks that assessed naming and comprehension of high-imageability as well as low-imageability nouns. These groups did not differ, however, in verb naming or comprehension on most tasks. Results are consistent with the hypothesized specialization of left temporal lobe structures for processing nouns and suggest that naming problems commonly seen after left ATL extend beyond difficulties with retrieving object names and may be related to subtle disturbances in comprehension of the meanings underlying nominal word forms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

CARE: Bridging the gap between clinicians and computers.

Psychologists and other mental health specialists have yet to capitalize on the enormous potential of computers as "clinical assistants." Many therapeutic uses of computers reflect overly ambitious if not naive uses of these machines, such as providing warmth and understanding to hurting persons. The present authors review previous applications of computers in health care, the nature and scope of computer resistance, the relative merits of people and machines in performing different kinds of tasks, and the ethical–legal issues involved when psychological services are provided by computers. Also presented is a relatively simple algorithm for an automated psychological service delivery system that provides, in response to specified complaint statements, low-level inference evaluations, concrete clinical advice, and modest referral information. The use of this computerized assistance, referral, and evaluation (CARE) system in a college community is described. (33 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Coping skills training for children: Effects on distress before, during, and after hospitalization for surgery.

Tested the hypothesis that coping skills (COS) intervention would help children adapt to hospitalization better than anxiety reduction (AR) or information interventions, using 33 parent–child dyads (children's mean age 7.2 yrs). All groups received the information procedure that described hospitalization and surgery experiences via a puppetry film. In the AR group, parents also learned procedures to help them reduce their own distress. Parents in the COS group learned how to help children use coping self-talk and related techniques. Results show that the AR and COS groups, compared to the information group, reduced children's self-reported fearfulness and parents' reported distress. The COS group, compared to the information group, exhibited fewer maladaptive behaviors during hospitalization and less problematic behavior in the preadmission week and 2nd postdischarge week. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cortical motor neuron activity in the cat during classical conditioning with central stimulation as the CS and the US.

Studied the neuronal basis of associative conditioning in the cat by pairing stimulation of thalamocortical pathways as the CS with antidromic activation of pericruciate pyramidal tract (PT) cells as the UCS in a differential classical conditioning paradigm. For the 18 Ss in Exp I, the target thalamic nuclei for stimulation were nucleus ventralis posterolateralis (VPL) and nucleus ventralis lateralis. For the 10 Ss in Exp II, the target thalamic nuclei were VPL and nucleus cetromedian. Results show that thalamic stimulation was not an effective CS. The response of PT cells to thalamic stimulation did not change as a function of reinforcement with PT stimulation. These results do not support the hypothesis that the simple pairing of any 2 neural events is the essential mechanism underlying associative conditioning changes. Instead, they suggest that the combined activation of specific and nonspecific thalamic nuclei may be important in producing increases in responsiveness of PT neurons. (45 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Thinking about strategies during, before, and after making a decision

Oxidative radicals are demonstrably produced in malaria-infected erythrocytes. In order to verify the biochemical origin of these radicals, erythrocyte lysate was brought to acid pH to mimic the environment of the parasite food vacuole into which host cell cytosol is transferred during parasite feeding. Oxyhemoglobin, but not deoxyhemoglobin, is rapidly converted to methemoglobin at rates which decline with increasing pH. The rate of conversion is further increased in the presence of the catalase inhibitor 3-amino-1,2,4-triazole (3-AT) and the extent of inhibition of the lysate catalase increases upon acidification, implying that H2O2 is thus produced by the spontaneous dismutation of superoxide radicals generated during methemoglobin formation. Intact Plasmodium falciparum trophozoite-infected human red blood cells (TRBC) were shown to produce H2O2 and OH radicals about twice as much as normal erythrocytes, as evidenced by the inhibition of endogenous catalase activity in the presence of 3-AT and the degradation of deoxyribose, respectively. Increased H2O2 levels and catalase activity were found in both host cell and parasite compartments. No increase in H2O2 production over that observed in uninfected erythrocytes could be detected at the ring stage when host cell digestion is absent. H2O2 and OH radicals production in TRBC was considerably reduced when digestion of host cell cytosol was inhibited either by antiproteases (which reduce the proteolysis of imported catalase) or by its alkalinization with NH4Cl (which reduce methemoglobin formation). These results suggest that reactive oxygen species are produced in the parasite's food vacuole during the digestion of host cell cytosol, and are able to egress from the parasite to the host cell compartment.