Over decades of research has examined the relationship between affective state and attention. The general consensus is that positive affect leads to the broadening of attentional breadth, whereas negative affect results in the narrowing of attention focus (Easterbrook, 1959; Fredrickson, 2001). Given that positive affect is produced in secure and comfortable contexts, it allows attentional breadth to be broader for individuals to receive more information. In contrast, given that negative affect is usually emerged in dangerous and unfavorable situations, it forces attentional focus to be narrower for people to avoid survival threat. Affective state has also been shown to affect attentional blink, which is believed to be dependent on attentional breadth. Attentional blink (AB) indicates a temporal limitation of attention. It is characterized by the inability to identify the second visual target (T2) in the rapid serial visual presentation (RSVP) stream when it appears closely after the first target (T1) (Raymond, Shapiro & Arnell, 1992). According to the overinvestment theory, attentional breadth is an important mediator of attentional blink (Olivers & Nieuwenhuis, 2006). Specifically, boarder attentional breadth can prevent excessive allocation of attention and leads to attenuation of attentional blink, whereas narrower attentional breadth promotes over-allocation of attention and results in stronger attentional blink. As a mediator, attentional breadth was suggested to explain the relationship between affective states and the blink. Because positive affect is expected to broaden attentional breadth under the well-accepted traditional view, positive affect would also be expected to attenuate attentional blink. Previous studies have tested this hypothesis, and found that both induced and self-report positive affect reduce attentional blink (Olivers et al., 2006; Vermeulen, 2010). However, the well-accepted relationship between affective state and attention was later criticized to be incomplete. Gable and Harmons-Jones (2008, 2010) argued that earlier studies about the two emphasized only the valence dimension (i.e. positive or negative) of affective state but often neglected the motivation dimension (i.e. high or low), which they considered as a crucial component to determine the consequences on attention. Based on their argument, they examined how affective states varying in valence and approach motivation influence attention. The results showed that, regardless of the valence, low approach-motivated affects broaden attentional breadth while high approach-motivated affects narrow attention focus. These findings provided clear evidence that the size of attention depends on the motivation component of affective state. In other words, positive affect does not necessarily expand attentional breadth and negative affect does not certainly narrow attention focus. It further suggested a potential issue with previous studies among affective state, attention breadth and attentional blink. These previous studies may have unintentionally included only the low approach-motivated positive affect and high approach-motivated negative affect, so the unique contribution of valence and motivation were confounded. That could explain why their findings appeared to show a strong relationship among affective states, attention focus and attentional blink in such direction. Therefore, the aim of this study is to distinguish the effects of valenced and motivated affective states on attentional blink. This study will independently manipulate both valence and motivation of affective state to test for their contributions. Based on the studies of Gable et al. (2008, 2010) and overinvestment theory, attentional blink would be expected to depend on motivation, with low approach-motivated affect decreases attentional blink while high approach-motivated affect increases attentional blink. In addition to measure attentional blink, we will also attempt to replicate the results of Gable et al. using the local-global visual processing task, which is believed to be a direct measure of attentional breadth. If the conventional explanation for attentional breadth is correct, the affective states should have similar effects on our and their measures.