Developmental Effects on Odor Learning and Memory in Children^a

Abstract

The child version of the California Odor Learning Test (COLT) was designed to assess cognitive functioning in impaired and healthy children. The COLT's rationale was based on two assumptions. First, measures of cognitive functioning are a good index of severity or extent of brain damage if compared between normal and clinical populations. Second, the cognitive-mediated tasks of verbal odor recall, recognition and identification were suitable to evaluate cognitive functioning. The focus of this study was to determine the COLT's ability to detect developmental differences in odor learning and memory. The participants were 51 healthy children who were twice administered the COLT with a weekly delay between tests. They were ascribed to two age-groups (7-10 and 11-15 years old) according to levels of cognitive development. The COLT employed 22 common odors and included two sessions. In the first session, children learned two sets of six odors. The first set was presented three times, the second one once, during a single learning episode. Following learning, children recalled the odors of the first set by name at free recall and category-cued recall. The second session included the following tasks: long-term free odor recall and category-cued odor recall, odor recognition-memory and verbal odor identification. A series of analyses of variance (ANOVAs, p < 0.05) with age as between-subject variable and repeated measurements on recall revealed significant differences between the two groups on the number of odors correctly recalled by name both at free recall, category-cued recall, recognition and identification. There were differences in false alarms at odor recognition between the two groups. Children from both groups benefited from a learning effect over odor trials. A gender effect was found for odor free recall at retest. These results suggest that the COLT has the potential to serve as a useful tool in the assessment of cognitive functioning in children.

Developmental differences in memory for cross‐modal associations

“…The results of the present investigation are consistent with studies demonstrating that associative memory for other types of stimuli is worse in children than in adolescents and young adults (Beurhing & Kee, 1987b; Hund et al , 2002; Hund & Plumert, 2003; Plumert & Hund, 2001). The present findings also are in accordance with research showing inferior performance in children compared with young adults on other odour memory tasks, such as odour identification, recognition and recall (Jehl & Murphy, 1998; Lehrner et al ., 1999a; Murphy et al ., 1994; Pirogovsky et al ., 2006).…”

“…In addition to associative memory, there may be developmental differences in memory for olfactory stimuli. Although children match adults in their ability to detect odours, they do not reach adult‐level performance on tasks involving olfactory discrimination, identification or memory (Cain et al ., 1995, Jehl & Murphy, 1998; Lehrner, Glück & Laska, 1999a; Lehrner, Walla, Laska & Deecke, 1999b; Murphy, Anderson & Markison, 1994; Pirogovsky, Gilbert & Murphy, 2006; Stevenson, Mahmut & Sundqvist, 2007). This finding suggests that inferior performance among children on more cognitively demanding olfactory tasks, such as odour identification or recognition, is not due only to immature olfactory sensitivity.…”

Source and Item Memory for Odors and Objects in Children and Young Adults

“…2001; Rybash & Colilla, 1994). Our findings are also in accordance with studies demonstrating that children perform poorly compared to young adults on other odor memory tasks, such as odor recall and identification (Cain et al, 1995;Jehl & Murphy, 1998;Murphy et al, 1994). Cycowiz et al (2001) reported source memory for visual stimuli to be worse in children compared to adults, whereas this study found no differences between 7-to 10-year-old children and 18-to 24-year-old adults on source memory for visual stimuli.…”

“…Murphy et al (1994) found that using olfactory stimuli that were more familiar to children significantly increased performance on an odor identification task, suggesting that poor performance in children on odor identification tasks may be due to a lack of odor-specific semantic knowledge, which slowly develops through adolescence. Jehl and Murphy (1998) compared 7-to 10-year olds and 11-to 15-year-olds on olfactory recall and recognition tasks and found that younger children performed worse on both recall and recognition memory tasks compared to the adolescents. Poor odor memory in children may be related to immaturity in various brain regions including the frontal lobes.…”

Children’s Awareness and Uses of Odor Cues in Everyday Life: A Finland–France Comparison

“…Using standard methods of detection threshold or odor discrimination, memory, and identification, they enhanced our knowledge on developing human olfactory abilities (Jehl and Murphy 1998;Koelega 1994;Richman et al 1992Richman et al , 1995bStevenson et al 2007). However, approaches situated in more ecologically valid settings are needed to better understand how olfaction is effectively used in human everyday life.…”