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Published on: December 3, 2020
Antihistamine effects on prefrontal cortex activity during working memory process in preschool children: a
Takeo Tsujii1, Eriko Yamamoto, Takayuki Ohira
1Center for Advanced Research on Logic and Sensibility (CARLS), Mita 3-1-7, Minato-ku, Tokyo 108-0073, Japan. tuji@flet.keio.ac.jp
Insights
First-generation antihistamines like ketotifen impair cognitive function in preschoolers, unlike second-generation antihistamines. Near-infrared spectroscopy (NIRS) revealed differential brain hemodynamic responses to antihistamines in children.
Area of Science:
- Neuroscience
- Developmental Psychology
- Pharmacology
Background:
- Histamine H1 receptor antagonists (antihistamines) are common treatments for allergic conditions in young children.
- Understanding the neurocognitive effects of these medications in pediatric populations is crucial.
- Near-infrared spectroscopy (NIRS) offers a non-invasive method for assessing brain activity in children.
Purpose of the Study:
- To investigate the differential effects of first- and second-generation antihistamines on prefrontal cortex activity during a cognitive task in preschool children.
- To evaluate behavioral performance and hemodynamic responses following administration of ketotifen, epinastine, or placebo.
Main Methods:
- A double-blind, placebo-controlled study involving 15 healthy preschool children (mean age 5.5 years).
- Participants performed a spatial working memory task.
- Prefrontal cortex activity was measured using near-infrared spectroscopy (NIRS) by monitoring oxygenated hemoglobin concentration changes 3 hours post-ingestion of ketotifen, epinastine, or placebo.
Main Results:
- Ketotifen significantly impaired behavioral performance and reduced cortical activation in the lateral prefrontal cortex during the working memory task compared to epinastine and placebo.
- Epinastine did not produce significant sedative effects on neural response or behavioral performance.
- NIRS data indicated differential effects of antihistamine generations on brain hemodynamic responses.
Conclusions:
- First-generation antihistamines (ketotifen) can negatively impact cognitive function and prefrontal cortex activity in young children.
- Second-generation antihistamines (epinastine) appear to have minimal sedative or cognitive side effects in this age group.
- NIRS is a valuable tool for neuropsychopharmacological research in pediatric populations, demonstrating differential drug effects on brain function.
Abstract:
Histamine H1 receptor antagonists (antihistamines) are widely used for the treatment of allergic disorders in young children. This study examined the effects of antihistamine on prefrontal cortex activity in preschool children using near-infrared spectroscopy (NIRS), an emerging brain-imaging method suitable for psychological experiments, especially in young children. We examined the changes of oxygenated hemoglobin concentration in the prefrontal cortex while children performed a spatial working memory task, 3h after taking a first-generation antihistamine (ketotifen), second-generation antihistamine (epinastine), or placebo. Fifteen healthy preschool children (mean age, 5.5 years) participated. Ketotifen significantly impaired behavioral performance and cortical activation at the lateral prefrontal cortex in the working memory task, compared with epinastine and placebo. There were no sedative effects on neural response or behavioral performance after epinastine administration. This paper demonstrates for the first time differential sedation effects of first- and second-generation antihistamines on brain hemodynamic response in young children. Also discussed is the utility of the NIRS technique in neuropsychopharmacological studies of children.
