Anterior cingulate cortex activation is related to learning potential on the WCST in schizophrenia patients

The remediation of executive function in patients with schizophrenia is important in rehabilitation because these skills affect the patient's capacity to function in the community. There is evidence that instructional techniques can improve deficits in the Wisconsin Card Sorting Test (WCST) in some schizophrenia patients. We used a standard test/training phase/standard test format of the WCST to classify 36 schizophrenia patients as high-achievers, learners or non-retainers. All healthy controls performed as high-achievers. An event-related fMRI design assessed neural activation patterns during post-training WCST performance. Patients showed a linear trend between set-shifting related activation in the anterior cingulate cortex and learning potential, i.e. increased activation in high-achievers, a trend for increased activation in learners, and no activation in non-retainers compared to controls. In addition, activation in the temporoparietal cortex was highest in patients classified as learners, whereas in non-retainers activation was increased in the inferior frontal gyrus compared to controls and high-achieving patients. These results emphasize the relevance of the ACC's neural integrity in learning set-shifting strategies for patients with schizophrenia. Also, our results support the hypothesis that compensatory neural activation in patients with schizophrenia helps them to catch up with healthy controls on cognitive tasks.     

Adaptive memory: Stereotype activation is not enough

Studies have shown that survival processing leads to superior memorability. The aim of the present study was to examine whether this survival recall advantage might result from stereotype activation. To test this hypothesis, we conducted a pilot study and two experiments in which participants were primed with stereotypes (Experiment 1, professor and elderly person; Experiment 2, survival-stereotype). In Experiment 1, 120 undergraduates were randomly assigned to a survival, professor stereotype, elderly person stereotype, or moving scenario and rated words for their relevance to the imagined scenario. In Experiment 2, 75 undergraduates were given a survival, survival-stereotype (based on our pilot study), or moving scenario. Both experiments showed that survival processing leads to a greater recall advantage over the stereotype groups and control group. These data indicate that the mere activation of stereotypes cannot explain the survival recall advantage.     

Levels of unconsciousness and their formal structure

This brief essay replies to Carvalho's exposition of a formal approach to the concept of the unconscious which is originally due to Ignacio Matte Blanco (1908–1995), a psychoanalyst from Chile. It's a challenge – first because I have been largely unfamiliar with the details of Matte Blanco's approach, and second because the space available for this reply does not allow me to be as precise as Carvalho's essay no doubt deserves. I will start with some remarks about how I see Matte Blanco's system from a mathematical perspective and then try to relate it to some of the core features of Pauli's and Jung's thinking. I will conclude with a tentative proposal of how Matte Blanco's strata between full consciousness and most undifferentiated unconscious can be related to the tension between ontic and epistemic accounts.     

Patients and agents – or why we need a different narrative: a philosophical analysis

Background

The success of medicine in the treatment of patients brings with it new challenges. More people live on to suffer from functional, chronic or multifactorial diseases, and this has led to calls for more complex analyses of the causal determinants of health and illness.

Methods

Philosophical analysis of background assumptions of the current paradigmatic model.

Results

While these factors do not require a radical paradigm shift, they do give us cause to develop a new narrative, to add to existing narratives that frame our thinking about medical care. In this paper we argue that the increased focus on lifestyle and shared decision making requires a new narrative of agency, to supplement the narrative of “the patient”. This narrative is conceptually linked to the developing philosophy of person-centred care.

Conclusions

If patients are seen also as “agents” this will result in a substantial shift in practical decisions: The development and adoption of this narrative will help practitioners work with patients to their mutual benefit, harnessing the patients’ motivation, shifting the focus from treatment to prevention and preventing unnecessary and harmful treatments that can come out of our preoccupation with the patient narrative. It will also help to shift research efforts, conceptual and empirical, from “treating” and “battling” diseases and their purported “mechanisms” to understanding complex contributing factors and their interplay.

     

Extinction of conditioned inhibition through nonreinforced presentation of the inhibitor

In previous studies that have tried to extinguish conditioned inhibition through nonreinforced presentations of the inhibitor, researchers have repeatedly failed to find evidence for such extinction. The present study revealed that extinction can be achieved through nonreinforcement of the inhibitor, depending on properties of the reinforcer. In a human causal learning experiment, we found complete extinction in a scenario in which the reinforcer could take on negative values. Thereby, this scenario reflected the assumed symmetrical continuum on which associative strength can vary, according to the Rescorla-Wagner theory of associative learning. In contrast to this, the inhibitory cue retained its inhibitory potential in another condition, in which the scenario did not allow negative values of the reinforcer. nt]mis|Klaus G. Melchers has previously published under the surname “Lober.” Susann Wolff is now working at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, Germany     

Impairment of single-trial memory formation by oral methylphenidate in the rat

High synaptic concentrations of dopamine and/or norepinephrine can impair the working memory function of the prefrontal cortex and impede attention and learning. Methylphenidate, a dopamine and norepinephrine transporter blocker known to facilitate these cognitive processes at low doses, was hypothesized to interfere with memory storage at doses that may raise concentrations of these neurotransmitters to systemically disruptive levels. In the present experiments, a dose of 10.0mg/kg of this drug was administered to female and male Long-Evans rats using a novel oral administration procedure designed to model the normal mode of delivery to humans. It was found to interfere with single-trial memory acquisition in a delayed object recognition test, a spontaneous learning task that involves no appetitive or aversive motivator. The time that the rats spent in overt exploration of the to-be-remembered objects during the acquisition trial was not affected, suggesting that the drug may have impaired processes of memory formation independently of interference with attention.