The 180-degree rule is thought to help smooth the change between film shots. When two individuals are speaking to each other, there is an imaginary axis of action running between them. If the camera crosses this axis, it breaks the 180-degree rule. A violation of the 180-degree rule is thought to have negative effects on viewers’ enjoyment of films. The present study investigated this idea. Experiment 1 established that naive participants can detect violations in videos. Experiment 2 tested the putative negative effects of 180-degree rule violations. The results indicated that violations can confuse and disorient viewers. Critically, as revealed by Experiment 3, violations did not alter the viewers’ liking of a video: Viewers were as likely to prefer a video with a 180-degree violation as one without. Collectively, these data shed light on fundamental beliefs regarding the 180-degree rule, which may help inform filming decisions around film enjoyment.
Corticosterone is produced by the adrenal glands and also produced locally by other organs, such as the brain. Local levels of corticosterone in specific brain regions during development are not known. Here, we microdissected brain tissue and developed a novel liquid chromatography tandem mass spectrometry method (LC-MS/MS) to measure a panel of seven steroids (including 11-deoxycorticosterone (DOC), corticosterone, and 11-dehydrocorticosterone (DHC) in the blood, hippocampus (HPC), cerebral cortex (CC), and hypothalamus (HYP) of mice at postnatal day (PND) 5, 21, and 90. In a second cohort of mice, we measured the expression of three genes that code for steroidogenic enzymes that regulate corticosterone levels (Cyp11b1, Hsd11b1, and Hsd11b2) in the HPC, CC, and HYP. There were region-specific patterns of steroid levels across development, including higher corticosterone levels in the HPC and HYP than in the blood at PND5. In contrast, corticosterone levels were higher in the blood than in all brain regions at PND21 and PND90. Brain corticosterone levels were not positively correlated with blood corticosterone levels, and correlations across brain regions increased with age. Local corticosterone levels were best predicted by local DOC levels at PND5, but by local DHC levels at PND21 and PND90. Transcripts for the three enzymes were detectable in all samples (with highest expression of Hsd11b1) and showed region-specific changes with age. These data demonstrate that individual brain regions fine-tune local levels of corticosterone during early development and that coupling of glucocorticoid levels across regions increases with age.
The 180-degree rule is thought to help smooth the change between film shots. When two individuals are speaking to each other, there is an imaginary axis of action running between them. If the camera crosses this axis, it breaks the 180-degree rule. A violation of the 180-degree rule is thought to have negative effects on viewers’ enjoyment of films. The present study investigated this idea. Experiment 1 established that naive participants can detect violations in videos. Experiment 2 tested the putative negative effects of 180-degree rule violations. The results indicated that violations can confuse and disorient viewers. Critically, as revealed by Experiment 3, violations did not alter the viewers’ liking of a video: Viewers were as likely to prefer a video with a 180-degree violation as one without. Collectively, these data shed light on fundamental beliefs regarding the 180-degree rule, which may help inform filming decisions around film enjoyment.
Abstract Consumption of sucrose (table sugar) is high in much of the world. The effects of a maternal diet high in sucrose on the placenta and fetal brain remain unknown. In rats, maternal consumption of sucrose at a human-relevant level has effects on the mother’s physiology and steroids, as well as long-lasting and sex-specific effects on the adult offspring’s brain and behavior. In the mothers, there are metabolic effects of sucrose intake, such as impaired glucose tolerance, increased liver lipids, and increased adipose inflammation. In rat dams, sucrose intake also decreases corticosterone levels in the blood but not in the brain. In the adult male offspring, preference for a high-sucrose diet and a high-fat diet increases due to maternal sucrose intake. In addition, maternal sucrose intake increases motivation for sugar rewards in a progressive ratio schedule of reinforcement in adult male offspring. In adult female offspring, corticosterone levels increase in the blood and brain as a result of maternal sucrose intake. In this study, we investigated the underlying mechanisms of the observed behavioral and endocrine effects in the adult offspring. Here, we examined cytokines and anti-inflammatory steroids in the placenta, amniotic fluid, and fetal blood and brain. In our model, we feed rat dams either a high-sucrose diet (26% of kCal) or an isocaloric, matched, control diet (1% sucrose) 10 weeks prior to and during gestation. At embryonic day 19 (E19), we collected maternal blood, placenta, amniotic fluid, fetal blood, and fetal brain. We use Palkovits punch to microdissect the placenta and fetal brain. Next, we use a liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay, which is highly precise and specific, to measure multiple steroids (e.g. corticosterone, progesterone, estradiol, allopregnanolone). The method is highly sensitive, and we can measure neurosteroids in multiple regions of the fetal brain (e.g. prefrontal cortex, nucleus accumbens, hypothalamus, hippocampus). Moreover, we will examine steroidogenic enzymes and cytokines in the fetal brain and placenta. Preliminary data show distinct steroid patterns in amniotic fluid and fetal blood, as well as in different parts of the placenta.
Background: Home non-invasive positive pressure ventilation (NPPV) may improve chronic hypercarbia in COPD and patient important outcomes. The efficacy of home high flow nasal cannula (HFNC) as an alternative is unclear. Methods: We searched MEDLINE, EMBASE, Cochrane CENTRAL, SCOPUS, and Clinicaltrials.gov for randomized trials of patients from inception to March 31st and updated the search on July 14, 2023. We performed a frequentist network meta-analysis and assessed the certainty of the evidence using the GRADE approach. We analyzed randomized trials (RCTs) comparing NPPV, HFNC, or standard care in adult COPD patients with chronic hypercapnic respiratory failure. Outcomes included mortality, COPD exacerbations, hospitalizations, and quality of life (SGRQ). Results: We analyzed twenty-four RCTs (1850 patients). We found that NPPV may reduce death risk compared to standard care (relative risk [RR] 0.82 [95% CI 0.66 to 1.00]) and probably reduces acute exacerbations (RR 0.71 [95% CI 0.58 to 0.87]). HFNC probably reduces acute exacerbations compared to standard care (RR 0.77 [0.68 to 0.88]) but its effect on mortality is uncertain (RR 1.20 [95% CI 0.63 to 2.28]). HFNC probably improves SGRQ scores (mean difference [MD] -7.01 [95% CI -12.27 to -1.77]) and may reduce hospitalizations (RR 0.87 [0.69 to 1.09]) compared to standard care. No significant difference was observed between HFNC and NPPV in reducing exacerbations. Conclusion: Both NPPV and HFNC reduce exacerbation risks in COPD patients compared to standard care. HFNC may offer advantages in improving quality of life.
Attention can be shifted in the direction that another person is looking, but the role played by an observer's mental attribution to the looker is controversial. And whether mental attribution to the looker is sufficient to trigger an attention shift is unknown. The current study introduces a novel paradigm to investigate this latter issue. An actor is presented on video turning his head to the left or right before a target appears, randomly, at the gazed-at or non-gazed at location. Time to detect the target is measured. The standard finding is that target detection is more efficient at the gazed-at than the nongazed-at location, indicating that attention is shifted to the gazed-at location. Critically, in the current study, an actor is wearing two identical masks -- one covering his face and the other the back of his head. Thus, after the head turn, participants are presented with the profile of two faces, one looking left and one looking right. For a gaze cuing effect to emerge, participants must attribute a mental state to the actor -- as looking through one mask and not the other. Over the course of four experiments we report that when mental attribution is necessary, a shift in social attention does not occur (i.e., mental attribution is not sufficient to produce a social attention effect); and when mental attribution is not necessary, a shift in social attention does occur. Thus, mental attribution is neither sufficient nor necessary for the occurrence of an involuntary shift in social attention. The present findings constrain future models of social attention that wish to link gaze cuing to mental attribution.
ABSTRACT Androgens regulate behavioural flexibility, which is essential to adapt to a changing environment and depends on the medial prefrontal cortex (mPFC). Testosterone (T) administration decreases behavioural flexibility. It is well known that T is produced in the gonads, but T is also produced in the mesocorticolimbic system, which modulates behavioural flexibility. It is unclear how T produced in the brain versus the gonads influences behavioural flexibility. Here, we assess the effects of the androgen synthesis inhibitor abiraterone acetate (ABI) and long-term gonadectomy (GDX) on behavioural flexibility in two paradigms. In Experiment 1, ABI independent of GDX reduced the number of trials to criterion and perseverative errors in a strategy set-shifting task. Similarly, in Experiment 2, ABI but not GDX reduced perseverative errors in a reversal learning task. In subjects from Experiment 1, we also examined tyrosine hydroxylase immunoreactivity (TH-ir), and ABI but not GDX increased TH-ir in the mPFC. Our findings suggest that neurally-produced androgens modulate behavioural flexibility via modification of dopamine signalling in the mesocorticolimbic system. These results suggest novel roles for neurosteroids and possible side effects of ABI treatment for prostate cancer.
