Affect and between-meal snacking in daily life: the moderating role of gender and age

Objective: Affect-related energy intake from snacks remains relatively unexplored in daily life. This study examines the associations between momentary positive affect (PA) and momentary negative affect (NA) and subsequent energy intake from snacks. In addition, the moderating role of BMI, gender, age and level of education is investigated.

Design: Adults (N = 269), aged 20–50, participated in this study. Demographics were assessed in an online composite questionnaire. An experience sampling smartphone application was used to map momentary NA/PA and energy intake (kilocalories) from snacks in the context of daily life.

Main outcome measures: Energy intake from moment-to-moment self-reported snacks in real-life settings.

Results: A significant negative main effect of momentary NA on moment-to-moment energy intake was found. The higher the momentary NA, the lower the subsequent amount of kilocalories consumed. There was no main effect with regard to PA. Interaction analyses showed that men decreased their energy intake after experiencing NA, and increased their intake after experiencing PA. No associations were found in women. Additionally, young adults (20–30) increased their energy intake after experiencing PA. No associations were found in the other age groups.

Conclusion: Interventions aiming at reducing energy intake might also address PA-related snacking in young adults and men.     

Atrophy of the parietal lobe in preclinical dementia

Cortical grey matter atrophy patterns have been reported in healthy ageing and Alzheimer disease (AD), but less consistently in the parietal regions of the brain. We investigated cortical grey matter volume patterns in parietal areas. The grey matter of the somatosensory cortex, superior and inferior parietal lobule was measured in 75 older adults (38 cognitively stable and 37 individuals with cognitive decline after 3 years). Dementia screening 6 years after scanning resulted in nine AD cases from the cognitively stable (n=3) and cognitive decline group (n=6), who were assigned to a third group, the preclinical AD group. When regional differences in cortical volume in the parietal lobe areas were compared between groups, significant differences were found between either the cognitive decline or stable group on the one hand and preclinical AD individuals on the other hand in the inferior parietal lobule. Group membership was best predicted by the grey matter volume of the inferior parietal lobule, compared to the other parietal lobe areas. The parietal lobe was characterised by a differential atrophy pattern based on cognitive status, which is in agreement with the 'last-developed-first-atrophied' principle. Future studies should investigate the surplus value of the inferior parietal lobe as a potential marker for the diagnosis of AD compared to other brain regions, such as the medial temporal lobe and the prefrontal lobe.     

TMS effects on subjective and objective measures of vision: stimulation intensity and pre- versus post-stimulus masking

Transcranial magnetic stimulation (TMS) can be used to mask visual stimuli, disrupting visual task performance or preventing visual awareness. While TMS masking studies generally fix stimulation intensity, we hypothesized that varying the intensity of TMS pulses in a masking paradigm might inform several ongoing debates concerning TMS disruption of vision as measured subjectively versus objectively, and pre-stimulus (forward) versus post-stimulus (backward) TMS masking. We here show that both pre-stimulus TMS pulses and post-stimulus TMS pulses could strongly mask visual stimuli. We found no dissociations between TMS effects on the subjective and objective measures of vision for any masking window or intensity, ruling out the option that TMS intensity levels determine whether dissociations between subjective and objective vision are obtained. For the post-stimulus time window particularly, we suggest that these data provide new constraints for (e.g. recurrent) models of vision and visual awareness. Finally, our data are in line with the idea that pre-stimulus masking operates differently from conventional post-stimulus masking.     

My owner,right or wrong: the effect of familiarity on the domestic dog’s behavior in a food-choice task

Dogs are strongly influenced by human behavior, and they readily form bonds with specific humans. Yet these lines of inquiry are not often combined. The goal of this study was to investigate whether such bonds would play a role in how dogs behave in response to human signals. Using various types of signals, we compared dogs’ use of information from a familiar human (their owner) versus an unfamiliar human when choosing between two food containers. In some conditions, the owner indicated a container that gave food and a stranger indicated a container that did not; in other conditions, this was reversed. Dogs more often chose the container indicated by or nearest to their owner, even when this container never yielded a food reward. In two conditions, dogs chose at chance: a control condition in which both pointers were strangers and a condition in which the owner and stranger sat reading books and provided no social signal. This is the first study to directly compare owners to strangers in a single food-choice situation. Our results suggest that dogs make decisions by attending preferentially to social signals from humans with whom they have become familiar.     

Masked constituent letter priming in an alphabetic decision task

Abstract

The experiments presented here were designed to test whether the prior presentation of a letter in a word, nonword or a string of Xs facilitates the subsequent identification of this letter. Using briefly presented masked primes, clear facilitatory constituent priming effects were obtained in an alphabetic decision task (letter/non-letter classification) when prime letters were flanked by Xs, but the effects disappeared or were greatly reduced when the prime letter formed part of a consonant array (nonword primes). Evidence for word-letter constituent priming was also obtained but almost only for word-initial letten. These facilitatory constituent priming effects were strongest when the target letter was embedded in a string of hash marks and occupied the same relative position in this string as the prime letter in the prime string. The mediating role of letter representations in word recognition and the position-specific coding of character arrays are discussed in the light of these results.     

On Potential-Based and Direct Movements in Information Spaces

Learning can be portrayed as a movement in a state space. Potential-based explanations of such movements hold that learners use a gradient-descent process to minimize a potential function. Direct explanations hold that learning is specific to information for learning. This study contrasts specific hypotheses derived from these general approaches. Participants estimated the length of arrow shafts of Müller-Lyer displays. Experiment 1 shows that learning in this paradigm can indeed be portrayed as a movement in a state space. In Experiment 2 nonveridical feedback was used in such a way that the contrasted hypotheses predicted learning in opposite directions. No learning was observed. In Experiment 3, movements in the state space were observed with practice conditions in which one of the hypotheses specified a movement in the state space whereas the other did not specify any movement. A tentative explanation for these findings is that both hypotheses are partly correct. However, more than to the empirical findings for this particular task, the authors wish to draw attention to the distinction between potential-based and direct processes—a distinction that they consider of general importance for the understanding of learning.     

Is There Really Mental Disorder?

Proponents of the reality of mental disorder claim that mental disorder is ontologically real in the same sense that the variola virus and smallpox are ontologically real. The chief architect of the DSM-III revolution, Robert Spitzer (Zimmerman & Spitzer, 2005 Zimmerman , M. , & Spitzer , R. , L. ( 2005 ). Psychiatric classification . In B. J. Sadock & V. A. Sadock (Eds.), Comprehensive textbook of psychiatry (pp. 1003 – 1033 ). Philadelphia , PA : Lippincott, Williams, and Wilkins . [Google Scholar]), candidly admits that a diagnosis of primary mental disorder present must be arbitrary because the distress or social impairment under consideration could well be a normal-range reaction to stressful events. Based on Jerome Wakefield's harmful dysfunction thesis, Spitzer hopes that research in evolutionary psychology can solve the perennial “false positive” problem in psychiatric diagnosis. Interestingly, in 1988 Wakefield , J. ( 1988 ). Hermeneutics and empiricism . In S. B. Messer , L. A. Sass & R. L. Woolfolk (Eds.), Hermeneutics and psychological theory (pp. 131 – 150 ). New Brunswick , CT : Rutgers University Press . [Google Scholar] Wakefield argued that the study of meaning (i.e., human behavior and the products of human behavior, such as art and literature) could not be assimilated to empiricism (science), but evidently he subsequently changed his mind. The present paper sides with the 1988 Wakefield , J. ( 1988 ). Hermeneutics and empiricism . In S. B. Messer , L. A. Sass & R. L. Woolfolk (Eds.), Hermeneutics and psychological theory (pp. 131 – 150 ). New Brunswick , CT : Rutgers University Press . [Google Scholar] Wakefield. It is an illusion to hope that research in evolutionary psychology will reveal how people are supposed to react to stressful events and thereby rescue psychiatric diagnosis from the false positive problem. The identification of mental disorder will remain akin to the identification of pornography, i.e., a case of reification based on interpretation and moral reasoning. The fiction that mental disorder is real turns attention away from past and present conditions of living. This may serve some interests, but it is not likely to serve the patient's interests.