Running head : THE EFFECT OF CHOCOLATE-CRAVING ON LTM 1 The Effect of Chocolate-Craving on Long-Term Memory

By replicating the craving induction used in Tiggemann, Kemps, and Parnell’s (2010) experiment, I was able to test the effects that take place at the long-term memory level. The influence of craving between subjects (induced chocolate craving condition vs. control condition using coloured blocks) on undergraduate students’ results on both word-recall and wordfragment memory tasks (within subjects) (N=25) was examined. Induced chocolate cravers performed significantly more poorly on both explicit word-recall and implicit word-fragment tasks than did controls. The practical implication of findings from this study can provide enough evidence to assume that visually interacting with chocolate effects learning and should be used with discretion in the classroom or workplace in which complex cognitive tasks are performed. THE EFFECT OF CHOCOLATE-CRAVING ON LTM 3 The Effect of Chocolate-Craving on Long-Term Memory Foods high in sugar have addictive properties; they can cause craving until the need is met (Baker, Morse, & Sherman, 1986). The term ‘craving’ describes a motivational state in which an individual feels compelled to seek and ingest a particular substance (Baker, et al.). An example is chocolate, which may be the most craved food (Hetherington & Macdiarmid, 1993). This does not come as a surprise, as the hedonic appeal of chocolate derives from its sugar-to-fat ratio and its texture (Drewnowski & Greenwood, 1983). Consuming chocolate increases serotonin production and releases endorphins, making the consumer feel good after he or she eats it (Benton, 2004). Chocolate consumption is largely due to psychological triggers such as depression (Willner, Field, Pitts, & Reeve, 1998) instead of physiological triggers and hunger deficiencies like most other foods (Pelchat, 2002). The difference between hunger and craving depends on the intensity of the desire, a learned response that is not innate (Hetherington & Macdiarmid, 1993). Chocolate is highly craved, thus demanding attention and taking up limited cognitive resources at the working memory level with potential impairments at the long-term memory (LTM) level. Craving can give rise to negative consequences such as guilt following unwanted consumption (Macdiarmid & Hetherington, 1995), binge eating (Gendall, Joyce, Sullivan, & Bulik, 1998), and early dropout from weight-loss programs (Sitton, 1991). Recent research shows a further consequence: food cravings may impair cognitive performance (Kemps & Tiggemann, 2007). Food cravings interfere with cognitive tasks because working memory has a limited capacity. For example, chocolate craving-related thoughts often take precedence over other, THE EFFECT OF CHOCOLATE-CRAVING ON LTM 4 potentially more important information to be stored (Kemps, Tiggemann, & Grigg, 2009). This hinders absorption of material at the input level and interferes with task performance at the output level when information is needed for recollection (Kemps, Tiggemann, & Grigg, 2009). Chocolate-related stimuli are perceived as attractive and demand attention drawing attention away from other stimuli (Kemps & Tiggemann, 2007). Researchers who focus on the study of working memory use attention and reaction time as a focus of measurement. Adaptation to environmental cues occurs at the sensory processing level before being received at the working memory level (Baddeley & Hitch, 1974). If information is successfully attended to, it may be encoded in the long-term memory store for later retrieval. The most supported model of working memory is that of Baddeley and Hitch (1974) who focused on three main components of input, processing, and output during memory. The working memory triad includes the central executive, the phonological loop and the visuospatial sketch pad (Baddeley & Hitch, 1974). The central executive mediates information from both the phonological loop and the visuo-spatial sketch pad and accounts for the attentional control system responsible for updating information (Baddeley & Hitch, 1974). The phonological loop and the visuo-spatial sketch pad compete for verbal and visual processing that occurs simultaneously; there is limited storage capacity in the working memory vessel (Tiggemann, Kemps, & Parnell, 2010). The working memory model is particularly significant because researchers have examined craving-induced learning deficits on respective areas. The visuospatial sketchpad processes visual and spatial information in the world for understanding at the working memory level. Tiggemann, Kemps, and Parnell (2010) found evidence that chocolate craving stems mainly from visual stimuli. They examined the effect of visual stimuli using tasks that incorporated the visuo-spatial sketchpad to measure a potential THE EFFECT OF CHOCOLATE-CRAVING ON LTM 5 deficit after inducing chocolate craving in female undergraduate students. Participants who experienced chocolate cravings performed significantly worse than those who did not experience such cravings (Tiggemann, et al.). The relevance of inducing chocolate craving and measuring the visuo-spatial sketchpad is that chocolate craving is often induced as a marketing scheme, via commercials and billboards. Distraction that occurs at the working memory level may be due to the presence of chocolate but could also be a visual distraction (which happens to be chocolate). Tiggemann, Kemps, and Parnell (2010) asked half of their participants to refrain from eating chocolate twenty-four hours prior to participating in a study (craving group). Participants in the craving condition were given a chocolate bar to unwrap and have in front of them while completing a working memory task on the computer screen (Tiggemann, et al.). Participants in the control group completed an identical working memory task but with a coloured block as a distraction instead of chocolate. They found that the craving group performed significantly worse on the working memory task than did the control group. These results indicate that it is, in fact a highlycraved food, in this case chocolate and not just a visual distracter that causes the impairment. While the effects of craving on working memory have been examined thoroughly, the potential effects of craving on long term memory (LTM) have not been addressed. There are working memory deficits due to craving so it is possible to see learning deficits by inducing the same craving. If so, there may be a far greater strain put on learning that stems beyond the working memory level. In general there are two types of LTM: explicit and implicit (Tulving, 1972). Tulving’s theory of encoding specificity states that to access episodic and semantic memory: specific THE EFFECT OF CHOCOLATE-CRAVING ON LTM 6 events in time and facts about the world, one must use retrieval cues during encoding similar to retrieval cues during activation of previously learned information. As noted, LTM deficits have not been demonstrated in craving conditions. The purpose of the current study is to compare LTM recall with participants who experience induced chocolate craving and individuals who do not. In keeping with previous research by Tiggemann et al. (2010), an elicited craving is induced using chocolate bars. Forgetting may be caused by a lack of appropriate retrieval cues such as hindered working memory, Tulving (1972) found evidence to support his encoding specificity principle with cued recall experiments using word lists. Forgetting may also be caused by a failure to encode an item in the first place. The storage in working memory is limited and distraction uses cognitive resources, restricting the information available for transfer to LTM storage for later retrieval. The present experiment tests decrements in long term memory storage stemming from working memory impairments using two well-established tasks of encoding—a word recall task to test explicit memory and a word fragment task to test implicit encoding of previously seen words in the recall list.