Altered multisensory temporal integration in obesity

Abstract

Eating is a multisensory behavior. The act of placing food in the mouth provides us with a variety of sensory information, including gustatory, olfactory, somatosensory, visual, and auditory. Evidence suggests altered eating behavior in obesity. Nonetheless, multisensory integration in obesity has been scantily investigated so far. Starting from this gap in the literature, we seek to provide the first comprehensive investigation of multisensory integration in obesity. Twenty male obese participants and twenty male healthy-weight participants took part in the study aimed at describing the multisensory temporal binding window (TBW). The TBW is defined as the range of stimulus onset asynchrony in which multiple sensory inputs have a high probability of being integrated. To investigate possible multisensory temporal processing deficits in obesity, we investigated performance in two multisensory audiovisual temporal tasks, namely simultaneity judgment and temporal order judgment. Results showed a wider TBW in obese participants as compared to healthy-weight controls. This holds true for both the simultaneity judgment and the temporal order judgment tasks. An explanatory hypothesis would regard the effect of metabolic alterations and low-grade inflammatory state, clinically observed in obesity, on the temporal organization of brain ongoing activity, which one of the neural mechanisms enabling multisensory integration.

Impaired Visual Motor Coordination in Obese Adults

“…This dissimilarity supports the findings of previous studies suggesting the existence of sensory integration deficiencies between obese and normal weight subjects [9, 10, 12, 13, 15]. It remains to be seen if these sensory integration problems exist prior to obesity and can be seen as a contributing factor to becoming obese or whether the development of obesity leads to detrimental consequences for the sensory integration process.…”

“…As fine motor skills are not directly affected by excess mass, this would suggest that other factors exist to impede obese individual's motor control [13]. This leads to the suggestion that the problem may lie in the sensory integration process [9, 10, 12, 13, 15]. …”

Body-scaled action in obesity during locomotion: Insights on the nature and extent of body representation disturbances

“…Critically, more recent studies suggest that an enlarged body might affect not only the subjective representation of bodily dimensions, meaning how people perceive the dimensions of their body parts, but also the perception of sensory bodily input; the perception of the intensity of peripheral pain [14][15][16], vibratory sensation and temperature [17],sense of satiety [18] and gastric motor functions [19] seem to be altered in obesity. Moreover, it was recently reported that people affected by obesity show alterations in the successful integration of multiple sensory input, such as audio-tactile stimuli [20] and audio-visual stimuli [21],anessential cognitive sensory process for successful actions in the environment. Consider the common behavior of walking: it results from a complex and unaware integration of different sources of information [22],suchas postural and sensory inputs related to the physical body size [23],dimensions and spatial position of possible obstacles [24],relationships between gait parameters and body proportions [25][26].…”

Sensory Loss Enhances Multisensory Integration Performance

“…Deviations in the temporal binding of multisensory stimuli have farstretching implications. A widened TBW, for example, leads to over-integration of stimuli and has been associated with a variety of clinical conditions, such as autism spectrum disorders, schizophrenia, dyslexia, and obesity Scarpina et al 2016;. In contrast, a narrow TBW has been linked to enhanced performance in both verbal and non-verbal problem solving tasks (Zmigrod and Zmigrod 2016) and individuals with a narrow TBW are less prone to be deceived by multisensory illusions, both when presented with simple perceptual and more dynamic stimuli (Stevenson et al 2012).…”