The scoring of arousals in healthy term infants (between the ages of 1 and 6 months) THE INTERNATIONAL PAEDIATRIC WORK GROUP ON AROUSALS* Accepted in revised form 28 July 2004; received 24 June 2004 SUMMARY Various definitions of arousals have been used in infants. An international group of experts has worked on a consensus for the scoring of arousals in healthy infants, aged between 1 and 6 months. This opinion paper summarizes the consensus statement on the scoring of arousal. The paper reviews recommended techniques for the recording of arousal in infants. Scoring includes the differentiation between subcortical activation, with no visible change n the electroencephalograph (EEG) recording, and cortical arousals associated with EEG changes. The arousals are further scored as spontaneous or induced, according to environmental conditions. Potential limitations to the method are discussed, with the hope that this document could contribute to promote further progresses in the scoring of infants arousals from sleep. keywords arousal, awakening, cortical, electroencephalography, infant, sleep, subcortical ANDRE ´ KAHN This consensus report is the result of the efforts of Andre´ Kahn who pursued this task with tenacity and enthusiasm, coordi- nating the contributions of many colleagues. We dedicate this report to his memory. AROUSALS IN INFANTS Arousals in infants have direct implications on various clinical conditions. An excessive propensity to arouse is found in infants suffering from insomnia and sleep disruptions, poten- tially associated with impairment of development (McNamara et al., 1999). An insufficient propensity to arouse could lower the chance to survive in infants exposed to noxious conditions during sleep (Philipson and Sullivan 1978), possibly increasing the risk for sudden death of infants (Newman et al., 1989). There is no uniform definition of arousal in infants. Various definitions have been used in infants of different ages, studied in different clinical and environmental conditions (American Thoracic Society 1996; Coons and Guilleminault, 1985; Crowell et al., 2002; Davidson Ward et al., 1992; Ficca et al., 1999; Franco et al., 1998; Galland et al., 1998; Hoppen- brouwers et al., 1993; Horne et al., 2001; Lijowska et al., 1997; McNamara et al., 1998; Mograss et al., 1994; Thomas et al., 1996; Wulbrand et al., 1997). Most definitions were close to or derived from the standard criteria laid out by the American Sleep Disorders Association (1992). It was felt that a consensus for the scoring of arousals and awakenings could contribute to facilitate comparison of results from different studies. To account for a description of arousal process (American Sleep Disorders Association, 1992; Hala`sz et al., 2004; McNamara et al., 1998; Moruzzi and Magoun, 1949; Steriade et al., 1996; Wulbrand et al., 1997), definitions should include a scoring of the level of arousal activation, such as subcortical or cortical involvement. THE INTERNATIONAL PEDIATRIC WORK GROUP An international pediatric work group was set up by sleep experts with the aim to define a method for the scoring of arousals in infants. The members of the group are listed in the Appendix. Between 1998 and 2002, polygraphic recordings of healthy infants were analysed. A scoring method was elaborated and preliminary technical reports were published (Groswasser, 2002; Kato et al., 2003). These scoring rules are recommended for scoring arousals from sleep in healthy infants, born at term, and studied between the ages of 1 and 6 months of life. Correspondence: Patricia Franco, University Hospital for Children, Av. J.J. Crocq 15, B-1020, Brussels, Belgium. Tel.: + 32 2 477 32 37; fax: + 32 2 477 27 55; e-mail: Patricia.Franco@ulb.ac.be *See Appendix J. Sleep Res. (2005) 14, 37–41 Ó 2005 European Sleep Research Society 37