Summary: In the inferior frontal gyrus, brain activity differs in response to food stimuli such as images of food depending on whether those images are presented consciously or unconsciously.
Source: Osaka Metropolitan University
Controlling your food intake can be even more difficult than you think. Osaka Metropolitan University scientists show that visual food cues can affect your eating behavior even when you are not aware of them.
Their findings were published in PLOS ONE.
Obesity is one of the major pathological conditions that constitute lifestyle-related diseases and is known to be associated with myocardial infarction, stroke, and carcinogenesis.
Approaches to regulate eating behavior are widely used in an effort to control obesity, but it has been reported that about half of those who receive dietary guidance return to their original weight within five years.
To explain the limited effectiveness of such guidance, one hypothesis suggests that not only conscious neural processes, which the dietary guidance targets, but also unconscious neural processes play an important role in controlling eating behavior. However, there were no studies directly examining the validity of this hypothesis at the level of neural activity.
The research team led by Professor Takahiro Yoshikawa from the Graduate School of Medicine at Osaka Metropolitan University has revealed that in the inferior frontal gyrus, a region of the brain’s frontal lobe that controls eating behavior, neural activity differs in response to visual food stimuli, or food images, depending on whether those images are presented consciously or unconsciously.
Using a questionnaire to assess the study participants, the team found that this difference was associated with their scores on eating behaviors, including emotional eating and cognitive restraint of food intake. These results indicate that eating behavior cannot be understood without taking into account both unconscious and conscious neural processes.
“If we can learn more in future research about how eating behavior is controlled by unconscious neural processes, we can combine that understanding with our current knowledge of conscious neural processes to potentially develop more effective methods for regulating eating behavior,” said Professor Yoshikawa.
About this behavioral and visual neuroscience research news
Author: Press Office
Source: Osaka Metropolitan University
Contact: Press Office – Osaka Metropolitan University
Image: The image is in the public domain
Original Research: Open access.
“Association between eating behavior and the immediate neural activity caused by viewing food images presented in and out of awareness: A magnetoencephalography study” by Rika Ishida et al. PLOS ONE
Association between eating behavior and the immediate neural activity caused by viewing food images presented in and out of awareness: A magnetoencephalography study
Obesity is a serious health problem in modern society. Considering the fact that the outcomes of treatments targeting appetitive behavior are suboptimal, one potential reason proposed for these poor outcomes is that appetitive behavior is driven more by unconscious decision-making processes than by the conscious ones targeted by traditional behavioral treatments.
In this study, we aimed to investigate both the conscious and unconscious decision-making processes related to eating behavior, and to examine whether an interaction related to eating behavior exists between conscious and unconscious neural processes.
The study was conducted on healthy male volunteers who viewed pictures of food and non-food items presented both above and below the awareness threshold.
The oscillatory brain activity affected by viewing the pictures was assessed by magnetoencephalography. A visual backward masking procedure was used to present the pictures out of awareness.
Neural activity corresponding to the interactions between sessions (i.e., food or non-food) and conditions (i.e., visible or invisible) was observed in left Brodmann’s areas 45 and 47 in the high-gamma (60–200 Hz) frequency range.
The interactions were associated with eating behavior indices such as emotional eating and cognitive restraint, suggesting that conscious and unconscious neural processes are differently involved in eating behavior.
These findings provide valuable clues for devising methods to assess conscious and unconscious appetite regulation in individuals with normal or abnormal eating behavior.