| Abstract: | 主計處在民國88 年調查發現有150 萬台灣人是檳榔嚼食者，嚼食者平均每天大約嚼14到 23顆檳榔。檳榔主成分檳榔鹼會影響中樞與邊緣神經系統，可能造成視覺訊息處理與注意力控制的改變。此外，檳榔嚼食與大腦的成癮機制有關（例如多巴胺系統以及鴉片接受器）。Robinson 與Berridge (1993, 2001, 2003)提出incentive-sensitization theory，認為長期使用成癮藥物或物質會改變與動機和獎賞有關的腦區，使得大腦系統對於成癮藥物或物質變得更加敏感，而這敏感的大腦系統會提高使用成癮藥物或物質的動機。在此三年計畫中，我們有兩個主要研究目的。一、檢驗檳榔嚼食者的對檳榔相關線索的注意力偏誤。我們分兩年運用成癮史楚普作業(實驗一)以及眼球追蹤儀(實驗二)來探討此議題。在實驗一，我們測量檳榔嚼食者對檳榔相關、香菸相關與酒相關刺激的注意力偏誤。我們認為高依賴的檳榔嚼食者會產生較大的檳榔相關刺激的注意力偏誤。此外檳榔嚼食者共用香菸和酒會影響對檳榔的注意力偏誤，且酒精依賴與煙依賴。實驗二測量在長時間(2000ms)呈現檳榔相關刺激下，嚼食者的注意力偏誤。我們認為在控制煙和酒精依賴後，嚼食者的眼睛會注視該刺激且有較長的停留時間。二、檢驗檳榔嚼食對訊息處理速度以及注意力控制的即時與長期影響。我們以attentional blink 作業(實驗三)以及mixed antisaccade 作業(實驗四)來檢驗此議題。我們認為嚼食檳榔後，檳榔嚼食者的訊息處理速度、抑制與轉換能力，會有顯著的提升。此能力的提升可能在高依賴嚼食者中更加明顯。
Directorate-General of Budget, Accounting and Statistic (1999) reported that about 1.5 million Taiwanese are betel nuts users, and about 30% of these users chew betel nuts for refreshment. An average of 14 to 23 betel nuts is chewed per day by one Taiwanese chewer. Betel nut chewing has been shown to play an important role in central and peripheral nervous systems. The changes observed in these systems owing to betel nut chewing plausibly suggest changes in visual information processing and attentional control. Betel nut chewing also plays important role in several brain activities that is related to its addicting effects. Robinson and Berridge (1993, 2001, 2003) proposed incentive-sensitization theory that claimed that repeated use of potentially-additive substance (e.g., arecoline in the current study) can produce long-lasting changes in brain systems involved in the process of incentive motivation and reward. As a result, these brain systems become hypersensitive to potentially-additive substances and substance-associated stimuli. These sensitized brain systems could mediate the motivation to approach and obtain the potentially-additive substance. In this three-year project, we have two major aims. First, we examine betel nut chewers’ attentional bias to areca-related cues. In two years, we adopt the addiction Stroop task (Experiment 1) and eye tracker (Experiment 2) to explore this issue. In Exp. 1, we measure betel nut chewers’ attentional bias to areca-, tobacco-, and alcohol-related cues. We hypothesize a larger attentional bias to areca-related cues in high-dependence chewers. Also, concurrent use of cigarette and alcoholic drink can also affect attentional bias to areca-related cues. In Exp. 2, we measure chewer’s attentional bias when the areca-related cues are present for 2000 ms. It is hypothesized that after controlling for tobacco- and alcohol-dependence, chewers’ gaze may fixate at the areca-related cues and have longer fixation time. Second, we examine how chewing betel nut affects information processing speed and attentional control (inhibition and switching). We use the attentional blink task and the mixed antisaccade task to explore this issue. We hypothesize that after chewing betel nut, the habitual chewers have better information processing speed and attentional control. This raised performance may be more significant in high-dependence chewers. |
