There are many faces of anxiety, ranging from totally fearful to merely nervous. New research now identifies areas in the brain, specific areas that are involved in different aspects of anxiety. Fear responses can be hard wired in the brain meaning that the brain is already afraid and it is our experiences that determines what the brain is afraid of. Thus, the reason that people have a more prolonged or exaggerated fear response is the interaction between their brain processes and the traumatic event. There are memory cells that allow fear to be re-activated. A painful event can cause freezing behavior leading to avoidance. This leads to new thoughts regarding therapy for Post Traumatic Stress Disorder. People can retrieve traumatic memories in the presence of something that interferes with their memory re-storage process and in that manner dampen the emotional impact of the remembered events, Neurology Today 12-3-2009.
Sleep deprivation affects the brain: judgment, impulse control, attention, emotions. Deprivation leads to slowing of motor skills, loss of cognitive thinking abilities. Prolonged deprivation can lead to hallucinations and psychosis. There is a link between sleep deprivation and high blood pressure, sleep allows the heart to reduce output for a significant amount of time, with no sleep the heart cannot rest. Decreased sleep affects insulin production and can lead to gained weight and insulin resistant syndrome as well as cellular changes contributing to fat accumulation.
Remember RLS, Restless Legs Syndrome? That is when there is an irresistible urge to move the legs, it starts or worsens during rest, it can be temporarily relieved by movement and is worse in the evening. Growing pains can be the pre-cursor to RLS. Growing pains can create poor sleep at night and hyperactivity during the day. RLS can create hyperactivity with the urge to move. RLS and ADHD overlap, proven by many studies. There is a higher propensity of ADHD in RLS and RLS in ADHD. ADHD established by testing was found to be more common in RLS than insomnia patients or controls (Wagner, Walters, Fisher, 2004). RLS found in population diagnosed with ADHD using neuropsychological evaluation (20 percent) (Zak, Fisher, Couvadelli, Walters, Moss, 2009).
Preschoolers: 4 and 5 year olds need about 10 to 12 hours
School age children and preteens: 6 to 12 years need about 10 hours
Teenagers need about 8 to 10 hours of sleep per night, requiring more sleep as their activity during the day increases.
Sleep is important to fight illness, deep sleep is important for learning as your dream sleep is for memory consolidation of what you have learned during the day. Not enough sleep can lead to sleep deprivation and sleep debt that accumulates. Napping prevents or creates problems getting to sleep that night which contributes to sleep deprivation and debt. Sleep debt needs to be made up on the weekend to avoid accumulation. Daytime sleepiness can create hyperactivity, problems learning, short term memory deficits and poor sustained attention.
Research supports the long held theory that ADHD is the result of abnormal chemical activity of the neurotransmitter, Dopamine. Lower availability of the dopamine receptor was noted in ADHD but not in controls using PET scans. Regions revealed signficantly lower dopamine transporter availability in specific brain areas providing confirmation of the important role of dopamine deficiencies in a specific brain circuit. The question is how this transmits clinically. The study alluded to the motivation system in the brain targeting the ADHD Impulsive, Hyperactivity but not the Inattention symptoms. This can become very convoluted in terms of understanding the symptoms of ADHD. If the subjects diagnosed with ADHD actually had symptoms of ADD plus meaning the impact to frontal processes then these findings would make sense however this then contributes to the continually held theory that ADHD involves the frontal processes which research studies have yet to clearly identify. Article from Neurology Today, 11-5-2009
Recent research shows that mild TBI can now be detected using Diffusion Tensor Imaging. Axonal injury can be seen in people who have suffered from mild brain injury using this type of imaging. This becomes particularly important when normal CT scans and normal MRI's result in people ruling out any impact to the brain when there actually may be damage occuring from an injury caused by a motor accident or fall. Too often people suffering from a brain injury are not heard regarding their complaints, they are assigned a diagnosis of malingering or conversion disorder, thought to be hysterical and overly dramatic. No one understands that their life has changed in a matter of minutes and they cannot function as they used to. Neuropsychological evaluation can document injury to the brain but then neuropsychologists argue if the damage actually exists. That is what makes radiological testing so important, it definitively documents injury that no one can argue about. DTI or Diffusion Tensor Imaging is a process, an application of the MRI that is sensitive to the direction of the movement of water molecules through tissue and can identify damaged axons by changes in the direction of the diffusion of water. Even more importantly, this process can identify frontal lobe white matter changes, a brain area commonly affected by TBI but typically unable to be measured. Neurology Today, Oct 2, 2009