Severe Memory Loss is an Early Indicator of Alzheimer’s Disease (March 14, 1997)
Sudden Attacks of Racing Heartbeats: Panic Disorder or Heart Disease ? (March 10, 1997)
How the Brain Makes the Right Decision ? (March 14, 1997)
Embryonic Nerve Cells Implant for Back Injuries (February 10, 1997)

Severe Memory Loss is an Early Indicator of Alzheimer’s Disease (March 14, 1997)

A new medical study has shown that elder persons who have early symptoms of memory loss of unknown cause have a higher probability of developing Alzheimer’s disease (48 %) when compared with patients of the same age and sex without memory loss (only 18 % develop the disease). Alzheimer’s disease is a devastating condition, also called senile dementia, which can affect a large proportion of elderly individuals, and which is characterized by impairments in abstract thinking, judgment, orientation, etc. It’s most characteristic condition is a great memory deficit. The causes of Alzheimer’s disease are unknown, but it is associated with extensive death of neural cells in several parts of the brain. The diagnosis of early memory loss may be used to pay more attention to patients at a higher risk.

Source: The Lancet (1997;349:763-765)

Panic Disorder or Hearth Disease ? (March 10, 1997)

Many women who think that they have the panic disorder, characterized by sudden and terrifying attacks of racing heartbeats, acute anxiety and fear, may in fact have a common, treatable, non-life threatening heart disease, called PSVT (paroxysmal supraventricular tachycardia). Clinical researchers in Detroit and Spokane have determined that 45 % of the women with this condition where misdiagnosed, often being told by the physician that their tachycardia (racing heartbeat) was emotional or stress related (twice more than men). Twelve percent of those underwent psychiatric treatment, and it took an average of more than three years to correctly diagnose the heart condition. More than 90 % of the patients with PSVT can be treated simply with medication.

Source: Archives of Internal Medicine

How the Brain Makes the Right Decision ? (March 14, 1997)

Making the right decision under difficult or emergency situation is a very important and complex process in the brain, still little understood by neuroscientists. The question is how the brain is able to signal the best course of action, given a number of possible behaviors, by using sensory information. Experimental research with monkeys which has recently been published in the journal Science now seems to imply that a neurotransmitter (substances that are secreted by nerve cell endings and which are used for communication between cells) called dopamine has a key role in the brain decision making processes. Researchers from Texas, USA and Fribourg, Switzerland, have determined this by implanting small electrodes (metallic wires used to record the electrical activity of neurons) in the brains of monkeys. The animals were trained to press a level in response to a visual pattern presented to them, in order to receive a reward of fruit juice. In this way, the scientists could measure the rate of electrical firing (reflecting the working of the dopamine-bearing neurons) when the amount of reward which was expected by the monkey was increased or decreased. The results of these experiments have shown that the dopamine neurons will increase their firing when the reward is higher than expected, and decreases it when the reward is less than expected. "The way the neurons change their predictions correlates with the behavioral changes of the monkey almost exactly", said one of the researchers, Dr. Montague.

SOURCE: Science (1997;275:1593-1598)

Embryonic Nerve Cells Implant for Back Injuries (February 10, 1997)

Dr. Scott Falci, of the Craig Center for Spinal Cord Injury Research, Denver, Colorado, USA, has performed in Uppsala, Sweden, for the first time a neurosurgical transplantation of human embryonic nerve cells to a patient with chronic spinal cord injury. The patient had develop scar tissue and a cyst in the spinal cord, causing loss of movement and sensation. The embryonic cells were placed in the spot, after removal of the scar tissue and cyst, in the hope that they would grow and fill the cavity, stopping further degeneration of the spinal chord. If the surgery works, this could be a revolutionary new procedure for treating many kinds of degenerative and injury-caused diseases in the brain. Currently, many countries (including the USA) do not allow the use of human embryonic cells for this purpose, however.