Improve our understanding of the processes that lead to specific
sleep disorders in children and adults. The following disorders
are included in this summary due to both their prevalence and
their impact on afflicted patients:
(difficulty initiating or maintaining sleep):
This should include the development of animal models of insomnia,
the study of specific insomnia phenotypes and the application
of neurophysiologic, neurochemical, neuroanatomic and functional
neuroimaging approaches to the study of insomnia in humans.
Understanding why women are at higher risk for insomnia should
be a goal as well. Finally, genetic, genomic and proteomic studies
are also needed.
Legs Syndrome (RLS) and Periodic Limb Movement Disorder (PLMD):
Studies should address the role of altered central dopaminergic
mechanisms and abnormal iron metabolism in their pathogenesis.
Further development, refinement and validation of animal models
of RLS and PLMD are also needed. The use of neuropathologic
techniques in the evaluation of brains and spinal cords of affected
patients are likely to be useful as well.
breathing (sleep apnea) and disorders of ventilatory control:
These studies should address the processes that control both
upper airway patency and ventilation itself with a particular
focus on the influence of sleep on these biologic processes.
The neural connections, neuromodulators and molecular events
mediating these state-dependent processes affecting respiration
during sleep need to be studied.
disorders leading to hypersomnolence: The neural
mechanisms leading to hypersomnolence in conditions such as
narcolepsy or primary central nervous system hypersomnolence
need to be investigated, and the focus these studies should
be how the neurobiologic causes of hypersomnolence differ from
or resemble the effects of sleep loss.
An assessment of
normal human sleep phenotypes and the normal range of variation
in this phenotype in adults and children (including
racial and ethnic differences) is needed, not only
to establish normative standards but also to serve as a model
for recommended sleep behaviors. This assessment should include
sleep duration, sleep stage distribution, sleep timing, sleep
disruption, sleep quality, and other variables by which sleep
and sleepiness can be quantitatively evaluated.
Once normal sleep
phenotypes are defined, the associated genotypes should be fully
Abnormal sleep phenotypes
should subsequently be recognizable and genotyping of these
individuals should then be pursued to define the genetic underpinning
of abnormal sleep or altered circadian rhythm profiles. The
impact of single nucleotide polymorphisms (SNPs)
on normal sleep phenotypes should be testable as well.
The phenotype of
patients with specific sleep disorders should be carefully defined
in order to set the stage for subsequent genetic testing.
Methods to define
normal and abnormal phenotypes through questionnaires or simple
non-invasive testing should be a goal. Population surveillance
and assessment of associated morbidities will then be possible
on a large scale.