The effects of a confectionery snack on attention in young boys
Introduction
Previous findings have shown that the administration of glucose improves performance on a variety of cognitive tasks, such as short-term memory [1], [2], [3], the rapid information processing task, the Stroop task, word recall [4], reaction to frustration and the ability to sustain attention [5].
Not all measures of cognitive processes, however, are enhanced by glucose ingestion. It seems that glucose enhancement of memory is type specific. For example, studies measuring digit span and paired associates have failed to find significant differences when subjects consumed glucose or a placebo [2]. In addition, measures of verbal declarative memory are enhanced by glucose ingestion, while measures of implicit memory are not [6]. It has been proposed that not all memory stores are equally sensitive to changes in blood glucose concentrations and this may account for the selective enhancement of certain tasks by glucose ingestion [6].
Despite the evidence that for some types of cognitive processes ingested glucose enhances cognitive performance, sugar consumption has often been associated with an inability to sustain activities for an appropriate period of time and difficulties organizing and completing work [7]. If an increase in blood glucose concentrations is related to hyperactivity, then attention should be negatively affected by the ingestion of glucose. However, the majority of studies do not support the idea that glucose consumption contributes to hyperactivity in normal children [8], [9] or children with attention deficit disorder [10]. A recent meta-analysis of the literature concluded that sugar does not have a negative effect on cognitive performance [11]. In fact, it has been suggested that the commonly reported negative effect of sugar on behavior may actually be due to parent's expectancies, rather than the sugar itself [12].
There are several possible reasons for the inconsistencies in the previous findings. One possibility may be the varying designs of the studies. For example, glucose may affect cognition differently depending on whether it is ingested following a meal or after a period of fasting [13] as well as the time of day it has been consumed [14]. In addition, differences among cognitive tasks, particularly with regard to memory and attention, may occur since these tasks involve different brain areas and thus may be affected differentially by the ingestion of a glucose load. Since glucose seems to enhance only certain types of cognitive processes, it is important to determine exactly which areas of learning and memory are significantly affected by intake of the carbohydrate. Consequently, the present study was designed to investigate the effects of a confectionery snack, containing predominately simple carbohydrates, on the performance of a wide variety of cognitive tasks critical to learning, including attention, visual perception, spatial memory, verbal memory and short-term memory. Finally, to determine, in the most sensitive way, which processes are affected, performance on the tasks was measured in the morning, after a period of fasting when the effects of a confectionery snack might be most pronounced.
Section snippets
Participants
Participants consisted of 21 fourth and fifth grade boys, between the ages of 9 and 12, attending a local, parochial elementary school. A screening questionnaire was administered to the parents/guardians of all interested volunteers. The questionnaire addressed current dietary and sleeping patterns as well as medical history. Children where allowed to participate in the study if they were of normal weight, and free of medication, learning disabilities and dietary restrictions. Parents/guardians
Attention
Dependent measures included response rates for hits, misses and false alarms. Participants had a hit when they correctly responded to the target (X followed by a B). A miss occurred when the participants failed to respond to the target. False alarms included all responses made to nontarget combinations. Response rates were examined overall and over time. For this latter analysis, the 10-min time period was broken down into three equal intervals (Time 1, Time 2 and Time 3) to represent the
Discussion
Results suggest that of the battery of cognitive tasks, only the task assessing attention showed significant differences between the confectionery snack and the placebo snack. When participants received the confectionery snack, performance on a vigilance attention task was significantly improved. With this snack, participants had significantly higher hit rates, and significantly lower miss rates than they did when they had the placebo snack. In addition, false alarm rates grew as a function of
Acknowledgements
We would like to thank Mars Inc. for providing the support for this project. We also thank Sr. Margaret M. Murphy and everyone at the St. Anthony School for their support and participation.
References (34)
- et al.
Blood glucose and human memory
PSYCHO
(1993) - et al.
Memory enhancement in elderly humans: effects of glucose ingestion
Physiol. Behav.
(1987) - et al.
Glucose enhancement on performance on memory tests of young and aged humans
Neuropsychology
(1989) - et al.
Blood glucose influences memory and attention in young adults
Neuropsychology
(1994) - et al.
Glucose improves attention and reaction to frustration in children
Biol. Psychol.
(1987) The role of glucose in regulating the brain and cognition
Am. J. Clin. Nutr.
(1995)- et al.
Functional food science and behavior and psychological function
Br. J. Nutr.
(1998) Effects of sucrose ingestion on the behavior of hyperactive boys
J. Pediatr.
(1985)- et al.
Sugar consumption, locomotion, task orientation, and learning in preschool children
J. Abnorm. Child Pyschol.
(1989) - et al.
The effects of sugar ingestion on the classroom and playgroup behavior of attention deficit disordered boys
J. Consult. Clin. Psychol.
(1986)
The effect of sugar on behavior or cognition in children
J. Am. Med. Assoc.
Effects of sugar ingestion expectancies on mother-child interactions
J. Abnorm. Child Psychol.
The influence of a glucose drink on a demanding working memory task
Physiol. Behav.
Psychological effects of snacks and altered meal frequency
Br. J. Nutr.
Comprehension and memory of narrative texts: inferences and coherence
Learning and memory
Effects of food snacks on cognitive performance in male college students
Appetite
Cited by (28)
Breakfast consumption and cognitive function in adolescent schoolchildren
2011, Physiology and BehaviorCitation Excerpt :Interestingly, in accordance with the present study, the effects of breakfast were only evident when looking at the accuracy of visual perception, with no effects on response times on the test of visual perception. A study conducted in 9 to 12 year old males also reported that there was no effect of breakfast consumption on response times (in accordance with the present study) or accuracy (in contrast to the present study) during the same Rey complex figure copy and recall test [21]. A potential explanation for this variation in findings could be that whilst the present study and the study of Mahoney et al. [2] compared breakfast consumption and breakfast omission, the study of Busch et al. [21] compared consumption of a confectionary snack and a non-calorie snack (control condition).
Meals, behavior and brain function
2009, Meals in Science and Practice: Interdisciplinary Research and Business ApplicationsEffect of an afternoon confectionery snack on cognitive processes critical to learning
2007, Physiology and BehaviorThe role of breakfast and a mid-morning snack on the ability of children to concentrate at school
2007, Physiology and Behavior