Sensory processing refers to the way individuals manage incoming sensory information, including its reception, modulation and integration with other brain areas and networks to produce an adaptive output to environmental demands . Since sensory systems provide the brain with ongoing information about the environment, adequate sensory processing is fundamental for proper cognitive and emotional function, for accurate movements, for learning, socializing and other activities that characterize our daily lives .
Altered sensory processing refers to difficulties to regulate and organize the intensity of response to sensory input in a graded and adaptive manner. Altered sensory modulation result in hypo or hypersensitivity to sensory input. Individuals with hypersensitivity respond to sensation faster, intensely and for a longer duration. They are overwhelmed with sensation and even experience “regular” stimuli as painful. This may lead to behavioral dysregulation expressed in stressful behavior, anxiety, irritability and avoidance from interactions with physical and social environments . On the contrary, individuals with hyposensitivity tend to miss sensory stimuli and thus fail to respond accurately to environmental demands .
Both hyper or hypo sensitivity may restrict adaptive behavior  and interfere with daily activity performance .
One of the theoretical models that refers to the interaction between the neurological-threshold to sensory input and the related behavioral regulation is Dunn’s model . According to this model, the interaction between the neurological threshold and behavioral regulation results in four patterns: (1) Low registration - people with high neurological thresholds (hyposensitive) and passive behavioral strategies that fail to detect sensory information and do not seek for it; (2) Sensory seekers - people with high neurological threshold who actively seek for rich and intense sensory stimuli (3) Sensory sensitivity – people with low neurological thresholds (hypersensitive) and passive behavioral, meaning they do not actively eliminate uncomfortable sensations; thus, they frequently experience discomfort, distraction, and emotional burden (4) Sensory avoiding - people with low neurological thresholds who actively limit their exposure to unpleasant sensations.
The very few studies that used Dunn’s model in older people, found that older people tend to show lower registration of sensory input, lower tendency to seek for sensory input and in some cases have modulation difficulties that result in hyper sensitivity. These alterations were found to significantly interfere with daily activity performance, with participation in daily situations and reduce quality of life [5, 6].
Nevertheless, most studies about sensory processing in the elderly focus on sensory acuity or sensory impairment in a specific sensory modality, mainly visual, auditory, vestibular [7–11], as measured in laboratory settings. Less is known about the ability of elderly people to process and integrate sensory information from various modalities, in daily life scenarios . Moreover, the literature emphasizes that the aging brain tends to rely increasingly on multisensory integration rather than a unisensory modality to compensate for deterioration in sensory systems and for changes in neural functioning . Hence, studies should further explore alterations in sensory processing in older adults, as expressed in all modalities and in daily life scenarios, in order to create better intervention programs, that are not relevant only for the clinical setting, but may be applied to daily environments. For that, studies should also elucidate the contribution of relevant factors responsible for behavioral regulation that affect the adaptive responses to environmental demands [13–15].
The high cognitive abilities responsible for behavioral regulation, for formulating goals, planning how to achieve them, and carrying them out effectively  are named executive functions (EF). EF are extremely affected by aging and significantly interfere with daily activity performance . Decline in EF in older adults, as a result from neurodegenerative changes  is related to deficient performance of instrumental activities of daily living (IADL), and impairment in elementary activities that enable keeping daily routines, such as: driving, money management, shopping [19–21]. The evaluation of EF in the elderly is also challenging – it is mainly based on laboratory neuropsychological/cognitive measures, which in many cases focus on specific aspects of EF such as inhibition; shifting, etc. with no referral to the implications on people’s daily function [22–23]. For that, ecological valid assessments that imitate daily scenarios are needed [24–26]. The Behavior Rating Inventory of Executive Function–Adult version (BRIEF-A)  which evaluates the expressions of the EF multicomponent in daily life scenarios is an example for an ecological valid assessment.
Very few studies refer to the association between sensory processing and executive functions.
The existing data collected on populations with CNS abnormalities such ADHD, brain injuries and CVA, found that altered sensory processing was related to reduced executive performances expressed for example in attentional problems, impaired working memory and inhibition problems [28–30].
Although studies show that altered sensory processing in the elderly affect daily activity performance, and may be related to executive dysfunctions, less is known about the contribution of EF to the effects of altered sensory processing on daily activities. Understanding how the ability to regulate behavior, manage action and decisions modulates the connection between altered sensory processing and daily function is of most important in intervention programs for improving daily function and quality of life in the elderly, in terms of understanding the role of these factor in determining functional resilience or vulnerability. Based on the above, this study aimed to profile altered sensory processing in older adults, in all sensory modalities, as expressed in their daily life and to explore whether EF mediate the relationship between sensory processing and the individual’s ability to perform daily activities. It was hypothesized that EF indeed mediate the relationship between sensory processing and daily activity performance.