Tuesday, October 3, 2017

Olfactory cues are more effective than visual cues in experimentally triggering autobiographical memories

Olfactory cues are more effective than visual cues in experimentally triggering autobiographical memories. Maaike J. de Bruijn & Michael Bender. Memory, http://dx.doi.org/10.1080/09658211.2017.1381744

Abstract: Folk wisdom often refers to odours as potent triggers for autobiographical memory, akin to the Proust phenomenon that describes Proust’s sudden recollection of a childhood memory when tasting a madeleine dipped into tea. Despite an increasing number of empirical studies on the effects of odours on cognition, conclusive evidence is still missing. We set out to examine the effectiveness of childhood and non-childhood odours as retrieval cues for autobiographical memories in a lab experiment. A total of 170 participants were presented with pilot-tested retrieval cues (either odours or images) to recall childhood memories and were then asked to rate the vividness, detail, and emotional intensity of these memories. Results showed that participants indeed reported richer memories when presented with childhood-related odours than childhood-related images or childhood-unrelated odours or images. An exploratory analysis of memory content with Linguistic Inquiry and Word Count did not reveal differences in affective content. The findings of this study support the notion that odours are particularly potent in eliciting rich memories and open up numerous avenues for further exploration.

KEYWORDS: Scent, olfaction, odour, autobiographical memory, Proust

Individuals who find food-related images more motivationally relevant than erotic ones may eat twice as much as their opposites

The reality of “food porn”: Larger brain responses to food-related cues than to erotic images predict cue-induced eating. Francesco Versace et al. BioRxiv.org,  September 5, 2017, https://doi.org/10.1101/184838

Abstract: While some individuals can defy the lure of temptation, many others find appetizing food irresistible. Using event-related potentials, we showed that individuals who find food-related images more motivationally relevant than erotic ones ("sign-trackers") are more susceptible to cue-induced eating and, in the presence of a palatable food option, eat twice as much as individuals with the opposite brain reactivity profile ("goal-trackers"). These findings contribute to the understanding of the neurobiological basis of vulnerability to cue-induced behaviors.

Perception of Causality: Categories and Constraints

Categories and Constraints in Causal Perception. Jonathan Kominsky et al. Psychological Science, last updated Sep 27 2017 https://osf.io/k8t4b/

Abstract: When object A moves adjacent to a stationary object, B, and in that instant A stops moving and B starts moving, people irresistibly see this as an event in which A causes B to move. Real-world causal collisions are subject to Newtonian constraints on the relative speed of B following the collision, but here we show that perceptual constraints on the relative speed of B (which align imprecisely with Newtonian principles) define two categories of causal events in perception. Using performance-based tasks, we show that triggering events, in which B moves noticeably faster than A, are treated as being categorically different from launching events, in which B does not move noticeably faster than A, and that these categories are unique to causal events (Experiments 1 and 2). Furthermore, we show that 7- to 9-month-old infants are sensitive to this distinction, which suggests that this boundary may be an early-developing component of causal perception (Experiment 3).

Acute exposure to blue wavelength light during memory consolidation improves verbal memory performance

Acute exposure to blue wavelength light during memory consolidation improves verbal memory performance. Anna Alkozei et al. PLoS One, September 2017, https://doi.org/10.1371/journal.pone.0184884

Abstract: Acute exposure to light within the blue wavelengths has been shown to enhance alertness and vigilance, and lead to improved speed on reaction time tasks, possibly due to activation of the noradrenergic system. It remains unclear, however, whether the effects of blue light extend beyond simple alertness processes to also enhance other aspects of cognition, such as memory performance. The aim of this study was to investigate the effects of a thirty minute pulse of blue light versus placebo (amber light) exposure in healthy normally rested individuals in the morning during verbal memory consolidation (i.e., 1.5 hours after memory acquisition) using an abbreviated version of the California Verbal Learning Test (CVLT-II). At delayed recall, individuals who received blue light (n = 12) during the consolidation period showed significantly better long-delay verbal recall than individuals who received amber light exposure (n = 18), while controlling for the effects of general intelligence, depressive symptoms and habitual wake time. These findings extend previous work demonstrating the effect of blue light on brain activation and alertness to further demonstrate its effectiveness at facilitating better memory consolidation and subsequent retention of verbal material. Although preliminary, these findings point to a potential application of blue wavelength light to optimize memory performance in healthy populations. It remains to be determined whether blue light exposure may also enhance performance in clinical populations with memory deficits.

Changing beliefs about past public events with believable and overtly unbelievable doctored photographs

Changing beliefs about past public events with believable and unbelievable doctored photographs. Robert Nash. Memory, http://dx.doi.org/10.1080/09658211.2017.1364393

Abstract: Doctored photographs can shape what people believe and remember about prominent public events, perhaps due to their apparent credibility. In three studies, subjects completed surveys about the 2012 London Olympic torch relay (Experiment 1) or the 2011 Royal Wedding of Prince William and Kate Middleton (Experiments 2-3). Some were shown a genuine photo of the event; others saw a doctored photo that depicted protesters and unrest. A third group of subjects saw a doctored photo whose inauthenticity had been made explicit, either by adding a written disclaimer (Experiment 1) or by making the digital manipulation deliberately poor (Experiments 2-3). In all three studies, doctored photos had small effects on a subset of subjects' beliefs about the events. Of central interest though, comparable effects also emerged when the photos were overtly inauthentic. These findings suggest that cognitive mechanisms other than credibility - such as familiarity misattribution and mental imagery - can rapidly influence beliefs about past events even when the low credibility of a source is overt.

KEYWORDS: Belief distortion, photographs, credibility, familiarity, images

Preliminary Evidence For Existence of Oral Sex in a Rural Igbo Community in Southeast Nigeria

Preliminary Evidence For Existence of Oral Sex in a Rural Igbo Community in Southeast Nigeria. Pavol Prokop, Ike E. Onyishi, Chiedozie O. Okafor & Michael N. Pham. Human Ethology Bulletin, Volume 32, No 3, 129-140,  https://doi.org/10.22330/heb/323/129-140

ABSTRACT: There is debate regarding whether oral sex recurred over human evolution. We investigated the occurrence of oral sex (cunnilingus and fellatio) and other sexual activities among a rural Igbo community in south-east Nigeria. We found that giving and receiving oral sex was less common relative to other sexual activities in both men and women. Both sexes reported more frequent vaginal sexual intercourse (particularly ventro-ventral posture compared with dorso-ventral posture) in the past 10 days compared to oral sex. Taken together, our data suggests that vaginal sexual activities follow similar patterns that are documented in other parts of world and that oral sex occurred less frequently in this traditional society.

Keywords: Evolution, human, Igbo people, oral sex.

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Oral sex is a common sexual behavior in humans and non-human animals (primates; short-nosed fruit bat; wolves)