Cardiac arrest: Mild to moderate hypothermia has been shown to preserve neurologic function following a cardiac arrest, during which the heart stops pumping and the brain is deprived of oxygen. In addition, recent studies have shown that hypothermia may also help improve short-term survival and minimize damage to the heart following such an injury. There are multiple theories as to why this is the case, including alteration of inflammation, slowing of metabolism, and reduction in cell death. It is apparent, however, that hypothermia can be a major benefit to victims of cardiac arrest.

Traumatic brain injury in children: Although hypothermia has been studied in adults with traumatic brain injury, its benefit may be especially prominent in children. As children’s brains are developing rapidly, any significant injury has the potential to cause serious long-term effects. Therapeutic hypothermia has been shown to reduce neurologic dysfunction as well as improve mortality.

Neonatal ischemic encephalopathy: Newborn infants who experience decreased oxygen flow to their brains are at great risk of developing brain damage. Hypothermia has been shown to improve not only their brain function but also their survival.

Stroke: There are some promising studies indicating that hypothermia may help improve recovery in stroke victims. At present, these studies are simply promising, but if validated by larger studies, the use of hypothermia for stroke victims may become more widespread.

Typically hypothermia is induced by using cool intravenous fluids and cooling blankets, but if only local hypothermia is needed the body part of interest can be packed in ice. Patients treated with therapeutic hypothermia may experience electrolyte disorders and may be at higher risk for pneumonia. Overall, however, in specific situations hypothermia can be useful adjunct medical treatment.

References

Hsu CY, Huang CH, Chang WT, Chen HW, Cheng HJ, Tsai MS, Wang TD, Yen ZS, Lee CC, Chen SC, Chen WJ. Cardioprotective effect of therapeutic hypothermia for post-resuscitation myocardial dysfunction. Shock. 2008 Dec 4.

David B. Seder, Salam Jarrah (2008). Therapeutic hypothermia for cardiac arrest: A practical approach Current Neurology and Neuroscience Reports, 8 (6), 508-517 DOI: 10.1007/s11910-008-0081-3

Patrick D. Lyden, Derk Krieger, Midori Yenari, W. Dalton Dietrich (2006). Therapeutic hypothermia for acute stroke International Journal of Stroke, 1 (1), 9-19 DOI: 10.1111/j.1747-4949.2005.00011.x

T HOEHN, G HANSMANN, C BUHRER, G SIMBRUNER, A GUNN, J YAGER, M LEVENE, S HAMRICK, S SHANKARAN, M THORESEN (2008). Therapeutic hypothermia in neonates. Review of current clinical data, ILCOR recommendations and suggestions for implementation in neonatal intensive care units? Resuscitation, 78 (1), 7-12 DOI: 10.1016/j.resuscitation.2008.04.027

Sven M Schulzke, Shripada Rao, Sanjay K Patole (2007). A systematic review of cooling for neuroprotection in neonates with hypoxic ischemic encephalopathy – are we there yet? BMC Pediatrics, 7 (1) DOI: 10.1186/1471-2431-7-30

Nadeem I. Shafi, M Michele Mariscalco (2006). Considering the use of induced hypothermia in a pediatric patient with traumatic brain injury: A critical appraisal of two meta-analyses Pediatric Critical Care Medicine, 7 (5), 468-472 DOI: 10.1097/01.PCC.0000235258.79253.8C

A new study presented at the annual meeting of the Radiological Society of North America reported that adults who exercise regularly exhibit increased blood flow to the brain, as well as more small vessels in the brain, compared with those who do not exercise regularly. This study posits that the differences in blood flow between exercisers and non-exercisers could explain why physical activity prevents cognitive decline as people age.

The researchers at the University of North Carolina at Chapel Hill evaluated 12 adults, aged 60 to 76 years old. Six of the subjects reported participating in aerobic exercise for 3 or more hours each week for the past 10 years. The remaining 6 subjects reported exercising less than 1 hour each week. The researchers conducted MRI scans and magnetic resonance angiography (MRA) of the patients’ brains and created 3-D models of the blood vessels. According to these models, the inactive group experienced more unpredictable blood flow through the brain, as well as possessing fewer small blood vessels than the active group.

As we age, our body — and brain — undergoes changes that can lead to physical and cognitive decline. Among these is the narrowing and loss of small blood vessels. Exercise reverses this blood vessel destruction in other parts of the body, so it is not surprising that it may have the same effect in the brain.

To date, most studies examining exercise and cognitive function focused on aerobic activity, and used prospective or retrospective study designs. Randomized clinical trials are needed to fully assess the impact of exercise on cognitive decline. Likewise, resistance exercise and other types of physical activity need to be considered, in addition to aerobic exercise, as beneficial in cognition. We already know that resistance exercise reduces morbidity and mortality in senior citizens, including decreased fall and fracture risk, and overall physical disability associated with aging.

Physical activity is valuable in the healthy aging process. Regular activity not only improves cardiovascular, respiratory, and muscular fitness, but also has positive effects on motor function, cognitive speed, memory function, and auditory and visual attention. Exercise also significantly improves mood in seniors and improves overall quality of life. The newest research demonstrates, once again, that the benefits of regular exercise are limitless. Routine physical activity should be encouraged for most patients, as part of a healthy aging process.

References

Angevaren M, Aufdemkampe G, Verhaar HJ, Aleman A, Vanhees L. Physical activity and enhanced fitness to improve cognitive function in older people without known cognitive impairment. Cochrane Database Syst Rev. 2008(3):CD005381.

Angevaren M, Aufdemkampe G, Verhaar HJ, Aleman A, Vanhees L. Physical activity and enhanced fitness to improve cognitive function in older people without known cognitive impairment. Cochrane Database Syst Rev. 2008(2):CD005381.

A. K Brown, T. Liu-Ambrose, R. Tate, S. Lord (2008). The Effect of Group-Based Exercise on Cognitive Performance and Mood in Seniors Residing in Intermediate Care and Self-Care Retirement Facilities: A Randomized Controlled Trial British Journal of Sports Medicine DOI: 10.1136/bjsm.2008.049882

T. Liu-Ambrose, M. Donaldson (2008). Exercise and Cognition in Older Adults: Is there a Role for Resistance Training Programs? British Journal of Sports Medicine DOI: 10.1136/bjsm.2008.055616

Rahman F, Smith J, Bullitt E, Katz L, Marks B. Relationship of exercise to cerebral vasculature and blood flow in older adults. Paper presented at: Radiological Society of North America; December 1, 2008; Chicago, IL.

Fast forward to the 21st century, electricity is now being explored for its potential to improve neurological function. A recent study at Beth Israel Deaconess Hospital and Harvard Medical School suggests that electrical stimulation of the brain may improve dexterity. In this study, 16 right-handed volunteers were fitted with scalp electrodes and weak noninvasive direct currents were transmitted through their skulls to neurons in the motor cortex. Prior to, and after each stimulation, the participants were asked to perform finger-sequencing tasks on a standard keyboard with the non-dominant hand.

The results were amazing. With electrical stimulation of the motor cortex, significant improvements in motor function in the non-dominant hand were seen. Dual stimulation of the right and left motor cortex regions, resulted in improvement of scores by almost 25%. Stimulating only one motor region showed a smaller increase (16%).

The mechanism of action, like ECT, is not is not clear. However, it is believed that transcranial direct current stimulation (tDCS) increases neuron excitability and may provide an environment supportive for motor skills recovery. Although the physiology is unknown, the implications and possible applications of this procedure is profound. Stroke victims, and people suffering from other conditions where motor function is lost or reduced may be able to acquire new skills or recover some lost motor function.

Reference

Bradley W Vines, Carlo Cerruti, Gottfried Schlaug (2008). Dual-hemisphere tDCS facilitates greater improvements for healthy subjects’ non-dominant hand compared to uni-hemisphere stimulation. BMC Neuroscience, 9 (1) DOI: 10.1186/1471-2202-9-103

For a large part of the previous century, it was believed that people with stroke would have to lead a largely dependent life, confined to the wheelchair. They were even discouraged from moving their limbs or exercising. Over the years, rehabilitation for patients with stroke has come a long way. Focus has shifted from basic interventions utilizing strengthening exercises to more advance techniques based on the theories of motor learning and neuroplasticity. This included manual techniques by skilled clinicians as well as the use of equipment such as electrical stimulation modalities, and specialized bikes and treadmill systems — all aimed at optimizing function in patients with impairments. In the past few years, a major step for the field of rehabilitation has been the integration of fields such as assistive technology, robotics and computer sciences with the science of rehabilitation. The amalgam of the above has led to potentially powerful systems that will enhance the functional outcome in patients greatly. The latest entrant into the filed of rehabilitation is virtual reality (VR) systems for rehabilitation. Many of the systems have been tested, released and are now available to hospitals and clinics for use. Clinical trials are ongoing, for upgrading existing technology and for invention of new systems for recovery and rehabilitation.

In 2002, the engineers at Rutgers University have created a VR system that included therapeutic activities aimed at recovery of function in patients with stroke. There are now many versions of this system available, and clinical trials are ongoing to evaluate the extent of efficacy of these systems in recovery of function. Like any VR gaming system, patients will see themselves in a simulated environment. Only, games will be replaced by targeted exercises that will work target various functional muscle groups in the arms and hands. Patients can complete fine motor tasks such as picking up objects, stacking objects, and gross motor tasks such as tapping balloons, catching objects and even reach for objects out of their base of support, thus encouraging balance retraining.

Of late, VR rehabilitation systems are also being evaluated for their use in decreasing neglect in patients with hemiplegia. This is achieved by the system providing visual cues from the affected side, to increase awareness and enhance adaptive relearning. A recent published case study (four participants) suggested that VR systems had the potential for decreasing neglect in patients with stroke. In addition to improvements on the objective tests that were administered, participants also subjectively reported that VR training sessions were helpful and enjoyable. VR systems can even simulate day-to-day situations like crossing a street, cooking, opening doors, etc. This will provide very specific learning of the tasks that are essential activities of daily living. The VR systems are effective as they emphasize active participation by the patient and provide varied environments for task practice while providing immediate feedback of quality. All of these fulfill the requirements of ideal motor practice and motor learning.

Stroke survivors, in my experience, are people who have the most enthusiasm to recover; their zest to go back to doing things they used to love serves as a wonderful motivator at rehabilitation sessions. Preserved cognition, high motivations levels, and a firm conviction to go back to their old routine makes patients with stroke ideal candidates for unique rehabilitation tools. I look forward to the day when these systems are available to most hospitals at an affordable price, with simpler user interfaces so that more and more patients will benefit from the systems.

Reference

Smith, J., Hebert, D., Reid, D. (2007). Exploring the effects of virtual reality on unilateral neglect caused by stroke: Four case studies. Technology and Disability, 19(1), 29-40.

Our job is to help restore function to patients with disabilities. We typically work hand-in-hand with a multidisciplinary team that may include physical therapists, occupational therapists, speech and language pathologists, recreational therapists, orthotists, prosthetists, clinical psychologists, social workers, vocational counselors, massage therapists, chiropractors, acupuncturists, or other doctors such as orthopedic surgeons, anesthesiologists, neurologists, rheumatologists, psychiatrists, or internists. Needless to say, a major prerequisite for being a physiatrist is being an excellent team player.

The physiatrist is like the conductor of an orchestra. We are the gatekeeper to a group of professionals who are good at what they do, but don’t necessarily know what the other people in the team do or how that affects the patient. The brass section doesn’t particularly care about what the strings are doing, or even know the first thing about how to play a violin. However, if the brass section is playing too loudly it can undermine what the strings are doing, and compromise the score as a whole. Only the conductor, who understands the bigger picture of the symphony, can put that whole puzzle together. In addition, the physiatrist brings their individual expertise into the picture. In particular, patients with heavily disabling injuries like traumatic brain injury (TBI) and spinal cord injury (SCI) are more or less managed exclusively by physiatrists (and the team that comes with them).

Because disability has so many faces, the field of PM&R has many facets to it. A general physiatrist is expected to know and master over a dozen disciplines including TBI, SCI, stroke, amputations, burns, musculoskeletal medicine, sports medicine, pain management, neuromuscular disorders, electrodiagnostics, cardiopulmonary rehabilitation, and pediatric rehabilitation. Since it is almost impossible to master all of these disciplines, most physiatrists end up subspecializing in 1 or 2 of them.

So what does all this mean to you? If you have any type of limitation in your activities, a physiatrist would be able to help. Not hitting that golf ball as far as you used to? Having trouble walking two city blocks when you used to be able to walk for miles? Is that pain in your knees really making it tough to climb a flight of stairs? Are you finding yourself having difficulty with swallowing foods? Any of these problems can be addressed by a physiatrist. We are here to help you function as well as your body will allow, and provide equipment and strategies to work around the things your body won’t allow.

The brain’s primary source of fuel is glucose, unlike other organs that have multiple fuel sources. Research has long shown that ingesting drinks or foods with high glucose content before high-demand short-term memory tasks improves cognitive performance. However, people with better blood-sugar regulation performed better on the tests than those with poor glucose regulation. In other words, the faster people metabolized blood sugar, the better their memory functioned.

Moderate increases in blood glucose are effective in enhancing short-term memory performance and cognitive functioning across an array of domains, but while a little glucose is good, too much can be bad. Sustained elevations in blood sugar levels, as seen in conditions including impaired glucose tolerance and diabetes, lead to a decline in cognitive functioning. Simply, the longer that the glucose remains in the blood, the less fuel the brain has to function and retain memories.

These findings are owed, at least in part, to the fact that glucose affects the hippocampus — the part of the brain responsible for short-term memory. In one small study, people with high blood sugar levels actually had a smaller hippocampus than those with normal glucose regulation. Any type of insult or injury to the brain, including high blood sugar, easily damages the hippocampus. Fortunately, it is also a resilient part of the brain and its function can be recovered when blood sugar levels are controlled.

Recently, elevated blood sugar levels were found to be significant predictors of poor cognitive performance or mild cognitive impairment among middle-aged and elderly subjects. Adults with higher fasting blood sugar levels performed worse on memory function tests, whether they received glucose or a placebo prior to the test. These findings are also linked to lifestyle factors. Study participants that had poor glucose regulation, leading to high blood sugar levels, had more risk factors for poor overall health, diet, and lifestyle. People with known risk factors for diabetes or impaired glucose tolerance are at risk for elevated blood sugar levels, in addition to any person who is overweight or has a sedentary lifestyle.

The research requires more investigation before glucose-regulation becomes a mainstay of memory loss treatments, but it provides more incentive for adults to maintain healthy blood sugar levels. Not only does a healthy, active lifestyle prevent heart disease, diabetes, joint ailments, and a plethora of other conditions, but it also improves memory and cognitive functioning.

References

Roozendaal, B. (2003). The hippocampus mediates glucocorticoid-induced impairment of spatial memory retrieval: Dependence on the basolateral amygdala. Proceedings of the National Academy of Sciences, 100(3), 1328-1333. DOI: 10.1073/pnas.0337480100

Meikle, A., Riby, L.M., Stollery, B. (2004). The impact of glucose ingestion and gluco-regulatory control on cognitive performance: a comparison of younger and middle aged adults. Human Psychopharmacology: Clinical and Experimental, 19(8), 523-535. DOI: 10.1002/hup.643

Riby, L.M., McLaughlin, J., Riby, D.M. (2008). Lifestyle, glucose regulation and the cognitive effects of glucose load in middle-aged adults. British Journal of Nutrition DOI: 10.1017/S0007114508971324

Riby, L.M., Marriott, A., Bullock, R., Hancock, J., Smallwood, J., McLaughlin, J. (2008). The effects of glucose ingestion and glucose regulation on memory performance in older adults with mild cognitive impairment. European Journal of Clinical Nutrition DOI: 10.1038/sj.ejcn.1602981

ADHD or attention deficit hyperactivity disorder is similar to AADD but research has shown that one third of the adults affected with AADD do not show any hyperactive behavior. Thus, the medical community has taken to using the AADD term instead.

In the brain of patients with AADD, executive function is impaired. This is the function that governs a person’s ability to monitor their own behavior by organizing and planning. This disorder affects approximately 2 to 4% of adults.

AADD patients are often the types seen by others as not thinking before they speak or act. They are sometimes referred to as a Type A personality or an always on the go individual. While they may seem to be driven, it is noted that they are rarely focused on one task long enough to see it to completion. In a recent study, three different groups of AADD patients all scored much lower than non-AADD adults on a dual memory and simultaneous capacity test, demonstrating their inability to concentrate in such situations. While this may seems like a small step, this recognition helps prove AADD to be a real concern.

As mentioned, treatment options vary depending on the severity of symptoms. For some AADD patients the symptoms are bad enough that medications along with social therapy are prescribed. Some of the more popular prescription medications are Ritalin, Adderall or Vyvanse. Ritalin is the most commonly known medication and is used in the treatment of ADD in children with some success. Adderall is a psychostimulant and Vyvanse (also used for children) is a stimulant as well.

It may seem strange that stimulants are prescribed for a disorder that sometimes causes hyperactivity but they are effective in many cases. This is thought to be accomplished by coaxing the brain to manufacture more serotonin. Increased serotonin has been shown to have a calming effect. This not only treats the hyperactive symptoms but may allow an adult to focus on their tasks at hand and see them to completion.

As recognition of AADD grows, more studies may lead to new treatments and an increased awareness of the disorder.

Reference

Dige, N., Maahr, E., Backenroth-Ohsako, G. (2008). Memory Tests in Subgroups of Adult Attention Deficit Hyperactivity Disorder Reveals Simultaneous Capacity Deficit. International Journal of Neuroscience, 118(4), 569-591. DOI: 10.1080/00207450701239384

The chemical link between the mind and body is best exemplified by the brain derived neurotrophic growth factor (BDNF), a protein found in our brain which helps brain cells to stay healthy, sprout new connections, and develop plasticity (the ability to form new connections between cells). Previous experiments have shown that short-term and long-term exercise both lead to a release of BDNF from various parts of our brain, more so from the cortex, basal forebrain and hippocampus, which are areas considered vital for learning, higher thinking, and memory.

A new study, published in Medicine & Science in Sports & Exercise, the official journal of the American College of Sports Medicine, actually confirms that the more intense the exercise, the more amount of BDNF released. The study, carried out at the Texas Tech University, recruited two groups of 15 cyclists who were assigned “heavy” and “light” graded intensity exercises. Their serum BDNF and mental cognition were measured before and after the test. While heavy exercises were associated with both increased BDNF levels and improved cognition test scores, the study has not conclusively demonstrated that the improvement in mental function due to heavy exercise is linked exclusively to increased BDNF release. According to Lee Ferris and James Williams, authors of the paper, the study could be underpowered (low numbers of cyclists), and future studies with larger numbers of participants could prove the definitive link.

However, this study, like other animal studies in the past on exercise-induced BDNF release, raises the issue whether regular aerobic exercise should be incorporated in fitness regimes aimed at the elderly and those with cognitive decline. Sweaty workouts could be more effective, as it turns out, than crossword puzzles in the regeneration of the aging brain.

Reference

Ferris L T, Williams J S, Shen C. The Effect of Acute Exercise on Serum Brain-Derived Neurotrophic Factor Levels and Cognitive Function. Medicine & Science in Sports & Exercise. 39(4):728-734, April 2007

Although an increased level of exercise can help improve mental activity, varying speculation on the benefits still exists. Nonetheless, authors Arthur F. Kramer, PhD, Kirk I. Erickson, PhD, and Stanley J. Colcombe of the University of Illinois at Urbana-Champaign said, “Our review of the last forty years of research does offer evidence that physical exercise can have a positive influence on cognitive and brain functions in older animal and human subjects.”

They used three different methods in their literature review. They first examined the literature pertaining to health and illness for indications that exercise or physical activity can improve cognitive ability and decrease age-related neurological diseases at certain periods of a person’s life. They then reviewed longitudinal, randomized trial studies to verify the effects exercise had on cognition in older adults. Lastly, they examined animal studies to understand the molecular and cellular mechanisms responsible for the effects of exercise on the brain, with particular regard to learning and memory.

One four-year study showed a direct relationship between exercise and improved cognition, function, and brain mass in older people. Kramer said that, in this study of people aged 62 to 70, “those who continued to work and retirees who exercised showed sustained levels of cerebral blood flow and superior performance on general measures of cognition as compared to the group of inactive retirees.”

In some of the studies they looked at, researchers had placed animals on wheel-running experiments, and other studies had used aged rodents in water-maze activities. Results showed that the aged rodents that exercised in a water maze learned and retained information about a hidden platform better than their age-matched controls.

Although more research is necessary to determine the quantity and type of exercise needed to produce rapid and significant effects on thinking, substantial support exists for the theory that exercise helps maintain mental activity as we age.

Reference

Kramer AF, Erickson KI, Colcombe SJ. Exercise, cognition, and the aging brain. Journal of Applied Physiology. 2006. 101(4);1237-42.