Boundary Conditions for the Positive Skew Bias.

Gambles that involve a large but unlikely gain coupled with a small but likely loss-like a lottery ticket-are known as positively-skewed. There is evidence that people tend to prefer these positively skewed choices, leading to what is called a positive-skew bias. In this study, we attempt to better understand under what conditions people are more drawn toward positively skewed, relative to symmetric, gambles. Based on the animal literature, there is reason to believe that preference for skewed gambles is dependent on the strength of the skew, with a greater preference for more strongly skewed options. In two online studies (Study 1: N = 209; Study 2: N = 210), healthy participants across the lifespan (ages 22-85) made a series of choices between a positively skewed risky gamble and either a certain outcome (Study 1) or risky symmetric gamble (Study 2). Logistic regression analyses revealed that people were more likely to choose moderately- and strongly skewed gambles over certain outcomes, with the exception of when there were large potential losses (Study 1). However, a stronger skewness did not increase preference for positively skewed gambles over symmetric gambles, findings which also may depend on the valence of the expected outcome (Study 2). Taken together, these results suggest that there may be a greater preference for more strongly positively skewed gambles but it 1) is dependent on what other gamble is presented and 2) is most prevalent for positive expected values. Additionally, contrary to previous findings, we did not find strong evidence of an age-related increase in positive skew bias in either study. However, exploratory analyses revealed that decision making strategy and cognitive abilities may play a role.

Adult Age Differences in Evoked Emotional Responses to Dynamic Facial Expressions.

OBJECTIVES: Facial expressions are powerful social signals that motivate feelings and actions in the observer. Research on face processing has overwhelmingly used static facial images, which have limited ecological validity. Previous research on the age-related positivity effect and age differences in social motivation suggest that older adults might experience different evoked emotional responses to facial expressions than younger adults. Here, we introduce a new method to explore age-related differences in evoked responses to dynamic facial expressions across adulthood. METHODS: We used dynamic facial expressions which varied by expression type (happy, sad, and angry) and expression magnitude (low, medium, and full) to gather participant ratings on their evoked emotional response to these stimuli along the dimensions of valence (positive vs negative) and arousal. RESULTS: As predicted, older adults rated the emotions evoked by positive facial expressions (happy) more positively than younger adults. Furthermore, older adults rated the emotion evoked by negative facial expressions (angry and sad) more negatively than younger adults. Contrary to our predictions, older adults did not differ significantly in arousal to negative expressions compared with younger adults. Across all ages, individuals rated positive expressions as more arousing than negative expressions. DISCUSSION: The findings provide some evidence that older adults may be more sensitive to variations in dynamic facial expressions than younger adults, particularly in terms of their estimates of valence. These dynamic facial stimuli that vary in magnitude are promising for future studies of more naturalistic affect elicitation, studies of social incentive processing, and use in incentive-driven choice tasks.

Temporal discounting across adulthood: A systematic review and meta-analysis.

A number of developmental theories have been proposed that make differential predictions about the links between age and temporal discounting, or the devaluation of future rewards. Most empirical studies examining adult age differences in temporal discounting have relied on economic intertemporal choice tasks, which pit choosing a smaller, sooner monetary reward against choosing a larger, later one. Although initial studies using these tasks suggested older adults discount less than younger adults, follow-up studies provided heterogeneous, and thus inconclusive, results. Using an open science approach, we test the replicability of adult age differences in temporal discounting by conducting a preregistered systematic literature search and meta-analysis of adult age differences in intertemporal choice tasks. Across 37 cross-sectional studies (Total N = 104,737), a planned meta-analysis found no sizeable relation between age and temporal discounting, r = -0.068, 95% CI [-0.170, 0.035]. We also found little evidence of publication bias or p-hacking. Exploratory analyses of moderators found no effect of research design (e.g., extreme-group vs. continuous age), incentives (hypothetical vs. real rewards), duration of delay (e.g., days, weeks, months, or years), or quantification of discounting behavior (e.g., proportion of immediate choices vs. parameters from computational modeling). Additional analyses of 12 participant-level data sets found little support for a nonlinear relation between age and temporal discounting across adulthood. Overall, the results suggest that younger, middle-aged, and older adults show similar preferences for smaller, sooner over larger, later rewards. We provide recommendations for future empirical work on temporal discounting across the adult life span. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Single-pulse stimulation of cerebellar nuclei stops epileptic thalamic activity.

BACKGROUND: Epileptic (absence) seizures in the cerebral cortex can be stopped by pharmacological and optogenetic stimulation of the cerebellar nuclei (CN) neurons that innervate the thalamus. However, it is unclear how such stimulation can modify underlying thalamo-cortical oscillations. HYPOTHESIS: Here we tested whether rhythmic synchronized thalamo-cortical activity during absence seizures can be desynchronized by single-pulse optogenetic stimulation of CN neurons to stop seizure activity. METHODS: We performed simultaneous thalamic single-cell and electrocorticographical recordings in awake tottering mice, a genetic model of absence epilepsy, to investigate the rhythmicity and synchronicity. Furthermore, we tested interictally the impact of single-pulse optogenetic CN stimulation on thalamic and cortical recordings. RESULTS: We show that thalamic firing is highly rhythmic and synchronized with cortical spike-and-wave discharges during absence seizures and that this phase-locked activity can be desynchronized upon single-pulse optogenetic stimulation of CN neurons. Notably, this stimulation of CN neurons was more effective in stopping seizures than direct, focal stimulation of groups of afferents innervating the thalamus. During interictal periods, CN stimulation evoked reliable but heterogeneous responses in thalamic cells in that they could show an increase or decrease in firing rate at various latencies, bi-phasic responses with an initial excitatory and subsequent inhibitory response, or no response at all. CONCLUSION: Our data indicate that stimulation of CN neurons and their fibers in thalamus evokes differential effects in its downstream pathways and desynchronizes phase-locked thalamic neuronal firing during seizures, revealing a neurobiological mechanism that may explain how cerebellar stimulation can stop seizures.

Aspirin desensitization for ASA triad patients--prospective study of the rhinologist`s perspective.

UNLABELLED: OBJECTIVES/PROBLEM: To determine the sinonasal effect of aspirin salicylic acid (ASA) desensitization in patients with nasal polyps, asthma and aspirin intolerance (ASA triad). METHODS OF STUDY: Patients with ASA triad were recruited from the outpatient otolaryngology clinic. They underwent a program of ASA desensitization (2005 - 2008) with prospective assessment of subjective and objective responses. Incremental doses of aspirin were given to reach a target of 625 mg twice daily during a period of 3 - 5 days. A maintenance dose was then given for the study period. The patients also received inhaled and topical nasal steroids, antihistamines and beta agonists for asthma control, but no systemic steroid treatment. MAIN RESULTS: Of the original 27 enrolled subjects, 10 elected to discontinue treatment and five dropped out because of treatment complications. The objective evaluation of the polypoid sinonasal disease in the remaining 12 patients (4 males, 8 females, age range 22 - 63 years) revealed only mild improvement. In contrast, the patients` subjective feeling of nasal congestion, nasal discharge and overall discomfort improved significantly. CONCLUSIONS: Aspirin desensitization has a favorable subjective effect on certain nasal symptoms among ASA triad patients, but the objective effect on polypoid mass is not significant.

Mathematical analysis of atelectasis formation in middle ears with sealed ventilation tubes.

AIM: A mathematical model was developed to identify time periods of atelectasis induction in middle ear (ME) ventilated via ventilating tubes (VT). Atelectatic ears are characterized by a total gas pressure lower than 760 mmHg. METHODS: Ventilating tubes were deliberately sealed and ME gas content changed in the presence of a preset blood gas pressure. Once sealed, CO2 rapidly diffuses out of the blood via lining tissues into the ME cleft. This results in initially a total ME pressure rise followed by a decrease in subatmospheric pressures. Time periods for atelectasis reformation was determined once ME pressure crossed the 760 mmHg value and continued to decline as the atelectasis reached higher grades. RESULTS: Time periods calculated by the model varied from 18 to 125 min in ME cavities ranging in volume from 0.5 to 3.5 mL, respectively. These results were calculated for conditions of venous blood in the lining mucosa blood and are consistent with prior clinical tests that measured an induced return to previous atelectasis state following the closure of the VT in 33 tested ears within 25-120 min (43 min on average). CONCLUSIONS: The model demonstrates that under the above conditions, diffusive gas transfer in relation to blood gas content is the leading mechanism to alterations in ME pressure and volume. It may be used as a tool to determine ME physiological cavity volume of ears with VT.

How can the hooded seal dive to a depth of 1000 m without rupturing its tympanic membrane? A morphological and functional study.

Recent studies using a satellite-linked dive recorder have shown that the hooded seal (Cystophora cristata), a common Arctic pinniped, can dive to a depth of > 1000 m and stay submerged for close to 1 h. At these depths the water pressure reaches 100 atm, entailing obvious risk of serious damage to the hearing apparatus, mainly the tympanic membrane (TM) and middle ear (ME). We dissected and photodocumented the temporal bones of five newborn and three adult hooded seals in order to study the temporal bone structure and reveal its protective mechanisms for extreme pressure changes. Specimens were sectioned and stained for light microscopy. The thicknesses of the pars tensa and pars flaccida were found to average 60 and 180 microm, respectively. The ME cavity hosts a cavernous tissue of thin-walled vessels beneath the modified respiratory epithelium. The ME and external ear canal (EAC) volumes can be altered appreciably by filling/emptying the cavernous tissue with blood. The ossicles were fixed by contracting the tensor tympani and stapedius muscles simultaneously with complete occlusion of the EAC. According to Boyle's law, the volume of the gas-filled ME cavity at a depth of 1000 m is only 1% of its volume at the surface of the sea. Ascent from such a depth allows the gas in the ME cavity to expand, causing the TM to bulge laterally. This movement is counteracted by a reduction in the blood volume inside the cavernous sinuses, action in the tensor tympani and stapedius muscles and discharge of gas through the Eustachian tube. The presence of a firm, broad-based exostosis in the floor of the EAC lateral to the TM helps to obstruct the EAC.

Hyperectasis: the hyperinflated tympanic membrane: the middle ear as an actively controlled system.

OBJECTIVE: To describe and analyze a middle ear condition in which the steady state of the middle ear pressure is elevated above the atmospheric pressure. SETTING AND STUDY DESIGN: This is a long-term survey of 59 patients from a private clinic who were observed on routine examination to have a ballooned out (hyperinflated) tympanic membrane. INTERVENTION: All patients underwent hearing tests, tympanometry, and Shullers (lateral) mastoid radiography. MAIN OUTCOME MEASURES: A hyperinflated tympanic membrane indicates a middle ear pressure that is higher than atmospheric pressure. The ballooned tympanic membrane returns to its physiological level after being punctured. This pressure situation is the reverse or opposite of atelectasis and is therefore termed hyperectasis. Hyperectasis, like atelectasis, is associated with a poorly pneumatized mastoid. RESULTS: Fifty-nine hyperectatic ears persisted in their hyperinflated state for weeks, months, or even years. The hyperectasis was preceded by atelectasis, and both conditions occasionally changed one into the other. The ballooned part of the tympanic membrane is usually thin and "scarred." Hyperectasis is not a rare situation and, once recognized, can be readily encountered in an otologic clinic. CONCLUSIONS: Like most biologic systems (e.g., blood pressure, temperature), the middle ear's central feature, i.e., pressure, also has a dynamic character vacillating up and down. It is conceivable that middle ear pressure is also actively regulated and controlled with the aid of a feedback mechanism. Passage of gas through the eustachian tube or absorption by diffusion-perfusion is also at least partly an active process. The up and down middle ear pressure vacillations are usually clinically benign and do not lead to any pathologic features as long as they are buffered by an accompanying normal mastoid pneumatization. It is the ear with a nonpneumatized mastoid that has limited ability to buffer pressure changes and that will present as an atelectasis, a retraction pocket, or (eventually a cholesteatoma) or their reverse, a hyperectatic tympanic membrane.

Surgical planning of the treatment of cholesteatoma and postoperative follow-up.

There is no single surgical treatment of choice for aural cholesteatoma. The extent of the cholesteatoma, the amount of preoperative destruction, and the size of the mastoid pneumatization should guide the surgeon in choosing the type of operation for a particular ear--which may range from a simple extraction of the cholesteatoma (delivery) all the way to a radical mastoidectomy. It is the clinical acumen that will determine the type of surgery for a given cholesteatomatous ear, algorithms being of little use in the complex situation of a pathological condition with infinite variables. However, even when the most suitable surgical modality is chosen by the best of surgeons, the operated ear will still be left with the innate cause of the cholesteatoma, namely, its physiopathologic background and its tendency to develop a negative gas balance in the middle ear. Because of this tendency to redevelop negative middle ear pressure, insertion and reinsertion of ventilation tubes are often necessary to prevent recurrent retractions and maintain aeration of the middle ear in posterior tympanotomies and modified radical mastoidectomies. Further, when the mastoid bowl is marsupialized, as in radical and modified radical mastoidectomies, the mastoid bowl is often not self-cleansing, thus periodically requiring the help of the otologist to keep it clean and dry. My study consisted of a long-term follow-up of 368 cholesteatomatous ears, which were operated on according to 6 different surgical modalities, ie, 112 radical mastoidectomies, 88 modified radicals, 72 posterior tympanotomies, 52 atticotomies, 36 deliveries, and 8 obliterations. Of the 368 ears, 11% did not require any postoperative toilet, whereas 89% required revisiting the surgeon periodically on an average of every 5 months, for cleansing of the mastoid cavity or securing the aeration of the middle ear by reinserting a ventilation tube.

The buffering effect of middle ear negative pressure by retraction of the pars tensa.

OBJECTIVE: To measure the middle ear (ME) volume displaced when the pars tensa (PT) retracts during conditions of atelectasis (AT). STUDY DESIGN: Measurements were carried out on AT tympanic membrane (TM). SETTING: Measurements were carried out on ambulatory patients in a private clinic. PATIENTS: Thirty-nine patients treated for otologic disorders who came for a routine follow-up. INTERVENTIONS: Quantitative assessment of ME volume displaced by retraction of the PT was achieved by measuring the amount of fluid needed to fill up the retracted part of a TM. The fluid-3% aqueous boric acid solution was colored with gentian violet. MAIN OUTCOME MEASURES: Retraction of the PT may prevent formation of high ME negative pressure by reducing the ME volume. Retraction of the PT acts as a pressure buffer according to Boyls law, in which volume x pressure = constant. RESULTS: Direct correlation was found between the degree of AT and the ME volume displaced by the AT. Measurements of 12 AT ears grade I showed them to have a volume of 5 microL to 31 microL (average, 19.5 microL) and ten AT ears grade II had a volume of 15 microL to 87 microL (average, 39.5 microL). Eight AT ears grade III had a volume of 26 microL to 67 microL (average, 54.3 microL), and nine AT ears grade IV had 80 microL to 200 microL (average, 130.6 microL). CONCLUSIONS: Retraction of the PT may counteract an important potential negative ME pressure (up to several hundred millimeters of water) depending on the degree of retraction and the extent of mastoid pneumatization.

Exostoses and cavernous venous formation in the external auditory canal of the hooded seal as a functional physiological organ.

Exostoses of the external auditory canal (EAC) develop after protracted mechanical, chemical or thermal irritation in particular. This is a common disorder among aquatic sportsmen and has been considered unique to Man. We dissected and photodocumented the EACs of 5 newborn and 3 adult Hooded Seals (Cystophora cristata). Serial sections of the EACs were prepared for light microscopic evaluation after staining with haematoxylin-eosin or toluidine blue. All EACs exhibited a firm, broad-based. mountain peak-shaped exostosis on the floor of the meatus, lateral to the eardrum. In addition, the meatal skin of the bony EAC harboured large venous sinuses. The exostosis and venous sinuses of the seal EAC participate in the protection of the sensitive hearing apparatus, particularly the pars tensa portion of the drum, during divine.

Eustachian tube teratoma and its terminological correctness.

Teratomas are germ cell tumours usually found in the young and are characteristically composed of tissue foreign to the place where they arise. Two teratomas of the middle ear were first described in 1866 and since then, and to the best of our knowledge, 19 additional cases have been reported in the literature under different terms such as hairy congenital polyps, epidermoid cysts, dermoid cysts, hamartoma, cutaneous teratoma and teratomas. The difficulty in classifying germ cell tumours may explain the different terminologies encountered in the literature. The authors describe a case of teratoma of the eustachian tube presenting as a mass in the middle and external ear of a 10-week-old girl. Using this case, a review of the literature is performed in light of the new classification of germ cell tumours proposed by the World Health Organization (WHO). It is of note that most of the teratomas that present in the middle ear arise from, or involve, the eustachian tube.

Mastoid buffering properties: I. Gas partial pressures.

Differences in the gas partial pressures between the middle ear (ME) cavity and the blood are an important factor in ME gas economy. Differences in gas partial pressures between various regions of the ME-mastoid air cell system (ME-MACS) could play a role as well. To determine whether gas partial pressure differences do occur between various compartments in the ME, we measured the rate of gas diffusion from one compartment to another in both an artificial model and in the ME-MACS of human temporal bones. The rate of gas diffusion between various areas of the ME and the mastoid tip was found to be rapid, with a half-life on the order of 2 minutes (range 0.8 to 5.3 minutes). We suggest that this high diffusion rate prevents the buildup of significant differences in gas composition in the ME-MACS system, which can therefore be regarded as a homogeneous gas pocket.

Quantitative analysis of gas losses and gains in the middle ear.

Quantitative analysis of the amount of gas entering and leaving the middle ear (ME) was performed in patients with central perforation or with ventilating tubes. Patients were divided into a 'balanced pressure group' (BP) where pressure remained close to atmospheric throughout the measuring period and an 'unbalanced pressure group' (UBP) where pressure decreased continuously throughout measurements. The rate of gas gain was 41.0 +/- 19.9 microl/h (mean +/- SD, n = 17) in the BP group, significantly higher than in the UBP group (21.4 +/- 9.6 microl/h, n = 8). The rate of gas loss was 34.8 +/- 17.7 and 36.1 +/- 15.9 microl/h in the BP and UBP groups, respectively. Deglutition frequency was 27 +/- 13.4 deglutition/h in the BP group, significantly higher than the deglutition frequency of the UBP group (16 +/- 8.9 deglutition/h). It seems that the amount of gas entering the ME per deglutition is rather stable and does not change significantly with ME pressure level. Negative ME pressure may result from decreased gas gain rate due to increased intervals between deglutitions and loss of interdependence between the rate of gas entering and leaving the ME.

Middle ear pressure variations during 50% N2O anesthesia as a function of mastoid pneumatization.

HYPOTHESIS: Mastoid size is a factor in middle ear (ME) pressure regulation. BACKGROUND: In a study investigating ME pressure variations during nitrous oxide (N2O) anesthesia, particularly high values of ME pressure increase rate (PIR) were observed in four patients with sclerotic mastoids. The current study is aimed at systematically assessing this observation. METHODS: Middle ear pressure was measured periodically in 30 patients during 50% N2O anesthesia using tympanometry. For each patient, a curve representing ME pressure during anesthesia was plotted. From the curve steepness, the PIR was calculated. Extent of mastoid pneumatization was assessed planimetrically using mastoid x-rays. Ears then were divided by the median into two groups: ears with small mastoids and ears with large mastoids. The difference between the mean PIR of both ear groups was statistically analyzed. RESULTS: A significant difference between the PIR was found among the two groups. In ears with mastoids smaller than 9.475 cm2 (the median), the PIR was significantly higher than in ears with mastoids > 9.475 cm2. CONCLUSIONS: These findings support the concept that the mastoid has a ME pressure buffering capability: the larger its volume, the better its buffering capability. It is therefore suggested, that the mastoid plays a role in ME pressure regulation.

Rate of gas exchange in the middle ear of guinea pigs.

Gas exchange between blood in the middle ear (ME) mucosa and ambient ME gas may be limited by diffusion through tissue or blood perfusion. In order to study the limiting factors in ME gas exchange, a hole was drilled in the bulla of 14 anesthetized guinea pigs through which a mass spectrometer probe was inserted and sealed in place. The rate at which oxygen (O2), carbon dioxide (CO2), nitrogen, and argon concentrations changed toward their steady state values was recorded. From the exponential fitted curves, gas rate constants (Kg) were calculated. The ratio KCO2/KO2 was 4:1, which is lower than expected from a diffusion-limited process in an aqueous compartment. The different rate ratios of CO2 and O2 indicate a diffusion-limited process. However, the deviation of the KCO2/KO2 ratio from that expected in aqueous solutions may indicate the involvement of a lipid compartment in gas exchange or other physiological mechanisms such as local acidity.

Revision myringoplasty.

This retrospective study was undertaken to review the short- and long-term results of 70 revision and 16 re-revision myringoplasty operations. Of the former, 43 cases (61.4 per cent) had initial success, six weeks following surgery. The leading causes of immediate failure (27 cases) were associated with a complete no-take of the graft, infection with graft necrosis and poor anterior adaptation of the graft in decreasing order. Six out of the 43 patients developed late re-perforations during the follow-up period, thus reducing the success rate of revision myringoplasty to 52.8 per cent. Late re-perforations were attributed to insidious atrophy of the tympanic membrane or episodes of acute otitis media. Sixteen patients underwent re-revision myringoplasty and their success rate was 62.5 per cent. The overall success rate of revision and re-revision myringoplasty was 54.7 per cent. It has been concluded that results of revision myringoplasty were independent of patients' age, location and size of perforation and the seniority of the surgeon.

Shrapnell membrane and mastoid pneumatization.

OBJECTIVE: To assess whether a correlation exists between the degree of pars flaccida (PF) retraction and the degree of mastoid pneumatization. DESIGN: The degree of PF retraction was defined by means of an operating microscope and a pneumatic otoscope. Degree of mastoid pneumatization was assessed planimetrically, using mastoid x-rays. SETTING: Private otologic clinic. PARTICIPANTS: A total of 595 ears, with intact pars tensa, of 332 adult patients. RESULTS: The degree of PF retraction was found to be inversely correlated to the level of mastoid pneumatization. Poorly pneumatized mastoids were associated with PF retractions. The poorer the pneumatization, the deeper the retraction. Well-pneumatized mastoids were associated with normal position of the PF. CONCLUSIONS: This study lends further support to the possibility that the mastoid pneumatic system functions as a middle ear pressure buffer. This possibility gives further explanation as to why ears with poorly pneumatized mastoids tend to develop tympanic membrane retractions and perforations, incus necrosis, or retraction pocket cholesteatoma, while ears with a large pneumatic system are rarely at such risk.

Correlation between retractions of the pars flaccida and the pars tensa.

Retractions of the pars flaccida (PF) and the pars tensa (PT) were assessed in 250 atelectatic ears in an attempt to find out the way in which the differences in mechanical properties of the two parts of the tympanic membrane are reflected clinically. Retraction of PF was found in 217 ears (86.8 per cent) and retraction of PF in 150 (60 per cent). The concomitant presence of both types of retraction was observed in 117 ears (46.8 per cent) while 133 (53.2 per cent) had only one type, 100 of them (75.1 per cent) PF retraction and 33 (24.9 per cent) PT retraction. When only one type of retraction was present, the empirical probability of having a PF retraction was 75.1 per cent, while the probability of having a PT retraction was only 24.9 per cent. Clinically, the more frequent occurrence of PF retraction in the absence of PT retraction than vice versa reflects the greater collapsibility of the PF. When both types of retractions were present, we found a positive correlation between their severity.