The role of social cognition in decision making

Successful decision making in a social setting depends on our ability to understand the intentions, emotions and beliefs of others. The mirror system allows us to understand other people's motor actions and action intentions. ‘Empathy’ allows us to understand and share emotions and sensations with others. ‘Theory of mind’ allows us to understand more abstract concepts such as beliefs or wishes in others. In all these cases, evidence has accumulated that we use the specific neural networks engaged in processing mental states in ourselves to understand the same mental states in others. However, the magnitude of the brain activity in these shared networks is modulated by contextual appraisal of the situation or the other person. An important feature of decision making in a social setting concerns the interaction of reason and emotion. We consider four domains where such interactions occur: our sense of fairness, altruistic punishment, trust and framing effects. In these cases, social motivations and emotions compete with each other, while higher-level control processes modulate the interactions of these low-level biases

The mystery of the brain-culture interface

Nature and culture work together to shape who we are. We are embedded in culture and are profoundly influenced by what those around us say and do. The interface between minds occurs at the level of explicit metacognition, which is at the top of our brain's control hierarchy. But how do our brains do this

Oral contraception and eye disease: findings in two large cohort studies

AIM : To investigate the relation between oral contraceptive use and certain eye diseases. \ud \ud METHODS : Abstraction of the relevant data from the two large British cohort studies of the effects of oral contraception, the Royal College of General Practitioners' (RCGP) Oral Contraception Study and the Oxford-Family Planning Association (Oxford-FPA) Contraceptive Study. Both cohort studies commenced in 1968 and were organised on a national basis. Between them they have accumulated over 850 000 person years of observation involving 63 000 women. \ud \ud RESULTS : The conditions considered in the analysis were conjunctivitis, keratitis, iritis, lacrimal disease, strabismus, cataract, glaucoma, retinal detachment, and retinal vascular lesions. With the exception of retinal vascular lesions, there was no consistent evidence of important increases in risk of eye diseases in users of oral contraception. There was about a twofold increase in the risk of retinal vascular lesions in recent pill users in both studies (statistically significant only in the RCGP study). The increase was not limited to any specific type of lesion and may well reflect diagnostic bias. \ud \ud CONCLUSION : Oral contraceptive use does not appear to increase the risk of eye disease, with the possible exception of retinal vascular lesions. \ud \ud Keywords: oral contraception; eye disease; cohort studie

Time-dependence in non-Hermitian quantum systems

In this thesis we present a coherent and consistent framework for explicit time-dependence in non-Hermitian quantum mechanics. The area of non-Hermitian quantum mechanics has been growing rapidly over the past twenty years [2]. This has been driven by the fact that PT -symmetric non-Hermitian systems exhibit real energy eigenvalues and unitary time evolution [1, 3, 4]. Historically, the introduction of time into the world of non-Hermitian quantum mechanics has been a conceptually difficult problem to address [5, 6], as it requires the Hamiltonian to become unobservable. However, we solve this issue with the introduction of a new observable energy operator [7]. We explain why its instigation is a necessary and natural progression in this setting. For the first time, the introduction of time has allowed us to make sense of the parameter regime in which the PT -symmetry is spontaneously broken. Ordinarily, in the time-independent setting, the energy eigenvalues become complex and the wave functions are asymptotically unbounded. However, we demonstrate that in the time-independent setting this broken symmetry can be mended and analysis on the spontaneously broken PT regime is indeed possible. We provide many examples of this mending on a wide range of different systems, beginning with a 2 x 2 matrix model [8] and extending to higher dimensional matrix models [9] and coupled harmonic oscillator systems with infinite Hilbert space [10, 11]. Furthermore, we use the framework to perform analysis on time-dependent quasi-exactly solvable models [12]. The ability to make sense of the spontaneously broken PT regime has revealed a vast array of new and exotic effects. We present the "eternal life" of entropy [13] in this thesis. Ordinarily, for entangled quantum systems coupled to the environments, the entropy decays rapidly to zero. However, in the spontaneously broken regime, we find the entropy decays asymptotically to a non-zero value. Finally, we create an elegant framework for Darboux and Darboux/Crum transformations for time-dependent non-Hermitian Hamiltonians [14]. This combines the area of non-Hermitian quantum mechanics with non linear differential equations and solitons

An fMRI study of joint action–varying levels of cooperation correlates with activity in control networks

As social agents, humans continually interact with the people around them. Here, motor cooperation was investigated using a paradigm in which pairs of participants, one being scanned with fMRI, jointly controlled a visually presented object with joystick movements. The object oscillated dynamically along two dimensions, color and width of gratings, corresponding to the two cardinal directions of joystick movements. While the overall control of each participant on the object was kept constant, the amount of cooperation along the two dimensions varied along four levels, from no (each participant controlled one dimension exclusively) to full (each participant controlled half of each dimension) cooperation. Increasing cooperation correlated with BOLD signal in the left parietal operculum and anterior cingulate cortex (ACC), while decreasing cooperation correlated with activity in the right inferior frontal and superior temporal gyri, the intraparietal sulci and inferior temporal gyri bilaterally, and the dorsomedial prefrontal cortex. As joint performance improved with the level of cooperation, we assessed the brain responses correlating with behavior, and found that activity in most of the areas associated with levels of cooperation also correlated with the joint performance. The only brain area found exclusively in the negative correlation with cooperation was in the dorso medial frontal cortex, involved in monitoring action outcome. Given the cluster location and condition-related signal change, we propose that this region monitored actions to extract the level of cooperation in order to optimize the joint response. Our results, therefore, indicate that, in the current experimental paradigm involving joint control of a visually presented object with joystick movements, the level of cooperation affected brain networks involved in action control, but not mentalizing

Physical activity, muscle-strengthening activities, and systemic inflammation among retinopathy patients

© 2018 by the American Diabetes Association. Objective. We evaluated the specific association between muscle-strengthening activity (MSA) and accelerometer-assessed physical activity on systemic inflammation among retinopathy patients in the United States. Methods. Data from the 2005–2006 National Health and Nutrition Examination Survey (NHANES) were used to identify 157 retinopathy patients between 40 and 85 years of age with complete data on select study variables. MSA was assessed via self-report. Participation in moderate-to-vigorous physical activity (MVPA) was determined from objective accelerometer data. Systemic inflammation was assessed using C-reactive protein (CRP), which was quantified using latex-enhanced nephelometry. Nonproliferative retinopathy was determined using Early Treatment Diabetic Retinopathy Study grading criteria, as well as objective retinal imaging assessments using the Canon Non-Mydriatic Retinal Camera CR6-45NM. Individuals were excluded if they had been diagnosed with coronary artery disease, congestive heart failure, heart attack, or stroke. Results. MVPA (β = –0.004, 95% CI – 0.007 to – 0.001, P = 0.006) but not MSA (β = –0.0001, 95% CI – 0.002 to 0.001, P = 0.86) was associated with lower CRP levels. Additionally, for a more substantive 30 minutes/day increase in MVPA, there was a corresponding 0.12 mg/dL decrease in CRP. Conclusion. In this nationally representative sample of adults, only individuals who engaged in higher levels of MVPA had lower CRP levels, which is indicative of reduced systemic inflammation. MSA was not associated with systemic inflammation among this cohort. Our findings suggest that MVPA is inversely associated with systemic inflammation among retinopathy patients, which is noteworthy because increased systemic inflammation may facilitate retinopathic severity

Association Between Perceived Physical Activity and Cognitive Function in Older Adults

© The Author(s) 2018. There is irrefutable evidence that regular participation in physical activity is favorably associated with numerous positive health outcomes, including cognitive function. Emerging work suggests that perceived physical activity, independent of actual physical activity behavior, is inversely associated with mortality risk. In this study, we evaluate whether perceived physical activity, independent of actual physical activity, is associated with cognitive function, a robust indicator of mortality risk. Data from the cross-sectional 1999–2002 National Health and Nutrition Examination Survey were employed (N = 2352; 60+ years of age). Actual physical activity was assessed via a validated survey. Perceived physical activity was assessed using the following question: “Compared with others of the same age, would you say that you are: more active, less active, or about the same?” Cognitive function was assessed from the Digit Symbol Substitution Test. When examined in separate models, both actual and perceived physical activity were positively and statistically significantly associated with cognitive function. However, when considered in the same model, actual physical activity was no longer statistically significantly associated with cognitive function, but perceived physical activity was. Perceived physical activity, independent of actual physical activity, is independently associated with cognitive function. If these findings are replicated, future work should consider evaluating perceived physical activity when examining the effects of actual physical activity behavior on cognitive function

Physical activity and cognitive function among older adults with an elevated gamma gap

© 2018 The Author(s) Published by S. Karger AG, Basel. Objective: An elevated gamma gap is indicative of high serum concentrations of globulin proteins, some of which elicit acute inflammatory responses. An impaired cognitive function has been linked to central and peripheral inflammation, while exercise is associated with protective, anti-inflammatory benefits. In this study, we evaluated whether the gamma gap is associated with cognitive function among older adults and whether physical activity is favorably associated with cognitive function among those with an elevated gamma gap. Materials and Methods: Data from the 1999-2002 National Health and Nutrition Examination Survey (NHANES) were used to identify 2,352 older adults aged between 60 and 85 years. The gamma gap was evaluated by subtracting albumin from total protein, i.e., gamma gap = total protein (g/dL)- A lbumin (g/dL). Those at or above 3.1 g/dL (31.0 g/L) were considered to have an elevated gamma gap. The Digit Symbol Substitution Test (DSST) was used to assess cognitive function tasks of pairing and free recall among participants. Participants were asked open-ended questions about participation in leisure-time physical activity over the previous 30 days. Results: Those with an elevated gamma gap (DSST, 44.8) had a lower cognitive function score when compared to those without an elevated gamma gap (DSST, 50.1) (p \u3c 0.001). After adjustments, and among those with an elevated gamma gap, those meeting the moderate-to-vigorous intensity physical activity (MVPA) guidelines (vs. not meeting them) had a DSST score of 6.42 units higher (β = 6.42, 95% CI 3.85-8.99, p \u3c 0.001). Conclusion: In this national sample of older adults, the gamma gap was associated with cognitive function, and among those with an elevated gamma gap, meeting the physical activity guidelines was associated with a higher cognitive function. Relevant clinical implications are discussed, as the gamma gap may be predictive of the risk for early mortality and reduced quality of life. Experimental work is needed to investigate whether physical activity training programs are effective in reducing an elevated gamma gap and preserving optimal cognitive functioning among at-risk individuals