Over the past four decades, laboratory research has investigated the impact of evolutionarily "relevant" stimuli (e.g., dangerous animals from our ancestors' era) and compared them with ontogenetically fear-relevant stimuli (i.e., stimuli that evoke fear due to societal influences such as guns) and irrelevant-fear stimuli. Food stimuli are also noteworthy for their historical significance in human life and in eating disorders, but less explored. Overall, past studies indicated that fear learning and defensive reactions might stem from evolutionary roots. Physiological responses such as skin conductance responses were a primary method for measuring fear reactions, revealing that it is more challenging to diminish fear responses to those "evolutionarily relevant" stimuli (e.g., snake) than to less relevant ones (e.g., flowers). Moreover, the resistance to extinction in conditioning studies has been shown to be less evident with ontogenetic stimuli like guns. Furthermore, associative learning without awareness is typically observed with biologically fear-relevant stimuli, rather than with those relevant due to societal reasons.

These projects aim to investigate the subliminal processing of fear-relevant stimuli and its impact on attention and physiological responses, as well as the emotional responses to stimuli such as food, examining both conscious and nonconscious responses. Both projects seek to expand our understanding of how different types of stimuli, both evolutionarily and societally relevant, affect human emotional and physiological responses, and employ subliminal presentation, including conditioning paradigms.