Costly habitual avoidance is reduced by concurrent goal-directed approach in a modified devaluation paradigm

Avoidance habits potentially contribute to maintaining maladaptive, costly avoidance behaviors that persist in the absence of threat. However, experimental evidence about costly habitual avoidance is scarce. In two experiments, we tested whether extensively trained avoidance impairs the subsequent goal-directed approach of rewards. Healthy participants were extensively trained to avoid an aversive outcome by performing simple responses to distinct full-screen color stimuli. After the subsequent devaluation of the aversive outcome, participants received monetary rewards for correct responses to neutral object pictures, which were presented on top of the same full-screen colors. These approach responses were either compatible or incompatible with habitual avoidance responses. Notably, the full-screen colors were not relevant to inform approach responses. In Experiment 1, participants were not instructed about post-devaluation stimulus-response-reward contingencies. Accuracy was lower in habit-incompatible than in habit-compatible trials, indicating costly avoidance, whereas reaction times did not differ. In Experiment 2, contingencies were explicitly instructed. Accuracy differences disappeared, but reaction times were slower in habit-incompatible than in habit-compatible trials, indicating low-cost habitual avoidance tendencies. These findings suggest a small but consistent impact of habitual avoidance tendencies on subsequent goal-directed approach. Costly habitual responding could, however, be inhibited when competing goal-directed approach was easily realizable.

Corticosterone Enhances Formation of Neutral but Not Fear Memory During Infectious Illness

Survivors of critical illness often report traumatic memories of their illness period, and these memories are thought to contribute to development of neuropsychiatric disorders, such as PTSD. Many patients are treated with high doses of glucocorticoids for their vasoactive and anti-inflammatory properties, and glucocorticoids have also been shown to prevent the development of PTSD after trauma. Due to their activity in the hippocampus and amygdala, the putative protective effect of glucocorticoids may occur via memory formation during illness. To examine the effect of glucocorticoids on memory formation during acute infectious illness, male and female C57BL/6 mice (N=80, 40 male/40 female) underwent cecal ligation and puncture and were treated with either corticosterone (16 mg/kg) or vehicle in the early afternoon daily for five days beginning on the day of surgery. All mice were habituated to a neutral object in their home cage for five days and underwent one 30-minute footshock/no shock training session during the illness period. After physiologic recovery (2 weeks), the mice underwent behavioral testing including open field exploration, object recognition testing in which they were presented with both the familiar (habituated) object and a novel object, and testing in the shock context. The results showed that drug treatment had no effect on behavior in the open field, including time spent in the center (VEH: 20.19±10.81 vs CORT: 22.32±12.87 sec; P=0.476). Drug treatment increased overall object exploration (12.28±10.79 vs 19.17±15.88 sec; P=0.049). Corticosterone-treated mice showed a preference for the familiar object (60.9±23.0% of total exploration time with familiar object; P=0.015), while vehicle-treated mice did not (54.1±23.3%; P=0.378). The increase in overall object exploration seen in corticosterone-treated mice could be accounted for by an increase in exploration of the familiar object. History of footshock increased freezing in the training context (3.96±2.54% vs 36.08±15.42%; P<0.0001) and corticosterone treatment had no effect (18.06±17.65% vs 22.16±21.19%; P=0.557). In conclusion, administration of corticosterone during infectious illness facilitated memory of a neutral object from the illness period, and recovered mice exhibited a preference for this object over a novel one. Corticosterone treatment had no impact on fear memory formed during illness. This is consistent with human literature suggesting that hydrocortisone decreases PTSD symptoms without impacting traumatic memories. These findings suggest that glucocorticoids selectively enhance the formation, consolidation, and/or recall of neutral but not fear memories during illness, which may rely on hippocampal circuitry. We further suggest that accurate memories of the illness period may influence patients’ perception of this experience and alter their risk for psychiatric sequelae.

Character Cues Modulate the Affordance Effects during Danger Warning

It has been demonstrated that perception of objects automatically evokes potential actions to interact with those objects; this is termed as affordance. The present study investigated how the corresponding affordance effect of graspable objects was modulated by the cue about risk levels of object. Participants were presented with pictures of dangerous graspable objects or neutral graspable objects. The participants were required to perform an upright/upside down discrimination task by pressing different keys. Results showed that both the affordance effects of dangerous object and neutral object in children were enhanced when a cue preceded the object, t(35) = 3.83, p < .01, Cohen’s d = 1.29. These results indicate that the prompt of risk level can improve individual’s appropriate manipulation to the object.

Roadblocks

For the most part, the gradual expansion of the meaning of “guy” to include everyone, male and female and GLBTQ, has slipped by without particular notice by the general public, and even by linguists. There’s no mystery about Guy Fawkes being the starting point that leads as far from that beginning as groups of women calling each other “you guys,” but neither is there much interest—except in two quarters that object: the feminist movement and the Old South of the United States. Feminists who want the inherently sexist English language to become gender neutral object to the expansion of “guys” to include women as well as men. As a result, some people try to avoid “guys,” though the alternatives aren’t that obvious, at best a plain “you all.” The other objection comes from Southerners, who don’t so much object to “guys” as keep to their well-established older alternative “y’all.” The boundary between “guys” or “you guys” and “y’all” has remained firm for the last century, perhaps getting its strength as one last means of holding the line against the northern states.

Serious limitations of the strong equivalence principle

It is well known that an accelerated charged particle radiates away energy. However, whether an accelerated neutral composite particle radiates away energy is unclear. We study decoherent Larmor radiation from an accelerated neutral composite object. We find that the neutral object’s long wavelength radiation is highly suppressed because radiation from different charges is canceled out. However, the neutral object radiates high energy or short wavelength radiation without any suppression. In that case, radiation from each particle can be treated independently, and it is called the decoherent radiation. We compare a hydrogen atom’s decoherent Larmor radiation with its gravitational radiation while the atom is in a circular orbit around a star. Gravitational radiation is stronger than the electromagnetic radiation if the orbital radius is larger than some critical radius. Since the decoherent radiation is related to the object’s structure, this implies that the strong equivalence principle which states that gravitational motion does not depend on an object’s constitution has severe limitations.

Symbolic Play Development in Toddlers With Expressive Specific Language Impairment (SLI-E)

Twenty toddlers with expressive specific language impairment (SLI-E) and 20 toddlers with normal language development were compared in their symbolic play development. The groups did not differ in amount of engagement with the toys or in functional conventional play behaviors. However, the children with SLI-E displayed less decentered play (use of play schemes with a doll or another person), less well-developed sequential play, and fewer occurrences of symbolic play transformations (use of a neutral object or an absent object to carry out pretending). The provision of structure in the form of thematically related toy sets, instructions, and modeling did not reduce the discrepancy between demonstrated play behaviors of toddlers with SLI-E and their normally developing peers. Three possible explanations for this discrepancy are considered: a "stylistic" difference in play, a developmental lag in symbol use, or a deficit in retrieval of stored symbolic representation.