Abstract
<jats:p>This section empirically investigates the effects of deceptive environmental claims (greenwashing), common in the fast-moving consumer goods (FMCG) sector, on consumers' visual attention mechanisms, cognitive load levels, and implicit emotional responses. To overcome the limitations of traditional statement-based scales, the research was conducted in a laboratory setting, integrating eye-tracking and electroencephalography (EEG) methods simultaneously. In the experimental process, 40 participants were presented with authentic greenwashing advertisements and manipulative greenwashing advertisements synchronously. The effect of the independent variable on neural outputs was tested using SPSS PROCESS Macro Model 4 (Full Mediation) structural path analysis, where eye-tracking fixation times played a mediating role. According to the eye-tracking analysis results, consumers focused on ambiguous text blocks and unsubstantiated eco-logos in greenwashing advertisements for statistically significantly longer periods (M = 3.450 ms) and more frequently compared to authentic advertisements. Path analysis outputs revealed that the type of deceptive advertising did not directly affect the cognitive load escalation in the brain (increased frontal theta power density) and the implicit brand avoidance reaction (negative frontal alpha asymmetry: M = -0.28); this process was entirely mediated through the prolongation of visual fixation time (full mediation). The findings empirically confirmed the hypotheses regarding mental strain and brand avoidance caused by greenwashing. This study is one of the pioneering researches in the sustainability-focused neuromarketing literature that chronologically and mechanistically maps the pathway of deciphering deceptive communication. The results demonstrate that, in contrast to the short-term visual attention-grabbing advantage of greenwashing strategies, they create a high biological cost (mental fatigue) in the consumer's prefrontal cortex within milliseconds, erecting an implicit wall of rejection towards the brand. The conclusions are as follows: This presents critical practical applications in the context of the necessity of biometric pre-testing protocols for advertising designers, green brand managers, and public policymakers.</jats:p>