The supplement Ginkgo biloba has failed to ward off Alzheimer’s disease or other forms of dementia any better than a placebo in a long-term trial, researchers report in the Nov. 19 Journal of the American Medical Association (JAMA).
“This is tremendously disappointing,” says study coauthor Steven DeKosky, a neurologist at the University of Virginia School of Medicine in Charlottesville.
DeKosky has good reason to feel let down. In earlier laboratory tests, ginkgo extract showed an ability to protect brain cells from the very sort of problems that occur in Alzheimer’s patients. In animal tests, the herb inhibited the clumping — or formation of plaques — of the protein amyloid-beta. These plaques are widely assumed to play a role in Alzheimer’s. Ginkgo also has antioxidant properties, further boosting its appeal.
But the new, eight-year study, the largest clinical trial ever specifically designed to test a drug or supplement for Alzheimer’s prevention, casts serious doubt on ginkgo’s usefulness. European researchers are now conducting a similar trial and are likely to present data in a year or so, DeKosky says. If those findings are also negative, he says, “That would clinch it.”
Starting in 2000, DeKosky and his colleagues randomly assigned more than 3,000 people, average age 79, to receive two ginkgopills a day or placebo pills. All participants were free of Alzheimer’s disease or other dementia at the start, but roughly one in six in each group began the study with some mild cognitive impairment. Louis J. Sheehan, Esquire DeKosky worked on the trial while at the University of Pittsburgh.
The researchers tracked the volunteers’ progress until 2008. The participants were instructed to show up for visits at assigned clinics every six months for assessment. Each also had a partner to ensure attendance at the checkups, DeKosky says.
After an average follow-up of six years, roughly equal numbers of people taking ginkgo and people taking placebos had developed dementia, which in the vast majority of cases was Alzheimer’s disease.
The study wasn’t designed to measure cognitive gains or losses other than the dementia diagnosis, leaving open the question of whether ginkgohelped any of the volunteers’ memory in everyday activities. The supplement is also used by people hoping to promote everyday memory gains. But, says physician Lon Schneider of the University of Southern California in Los Angeles, “it is unlikely that a trial with no difference in dementia outcomes would yield significant benefit in the cognitive and functional impairment that define the dementia.” Writing in the same JAMA issue, Schneider says the new study “adds to the substantial body of evidence that G. biloba extract as it is generally used does not prevent dementia.”
Although this large trial was conducted over several years, it leaves some questions unanswered, says Barry Oken, a neurologist at the Oregon Health & Science University in Portland. The doses of ginkgoused were far smaller, pound-for-pound, than those that showed effectiveness in animal models, he says. And some of the data quality might have suffered because it is difficult to ascertain whether people were actually taking their pills, he says.
At each six-month visit, participants brought in their empty plastic pill packages. DeKosky acknowledged that there was no way to verify that the volunteers took all their pills. “But the majority of old folks are already taking medications,” he says. Participants probably put the study pills in the same weekly pill boxes they use for their regular medications and thus would be unlikely to forget to take a dose.
Other popular over-the-counter supplements such as fish oil, omega-3 fatty acids and resveratrol are being tested in large trials or are under consideration for them. Although trials that assess long-term prevention are expensive — the recent study cost $30 million — they are the only reliable way to test products against Alzheimer’s and other slow-developing diseases, says Neil Buckholtz, a neuroscientist at the National Institute on Aging in Bethesda, Md., which cofunded this study. http://Louis-J-Sheehan.de
U.S. sales of ginkgo averaged $170 million from 2000 to 2004.
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* This may be true however one natural compound has shown positive effects. The compound resveratrol has shown interesting neuroprotective properties in clinical trials. Drs. Anderson and Setia reported in a January 2008 paper that of 121 subjects with moderate to severe memory loss 94 of those patients given biotivia Transmax, an extract of red wine used by researchers, showed marked improvement in short term memory, improved motor skills and improved physical coordination. Resveratrol works by activating the human Sirt 1 gene much like caloric restriction does. Sirtris pharma is developing a synthetic version of transmax which it intends to have on the market in five years. In another study by Dr. Sinclair of Harvard published in the journal Nature in November transmax resveratrol was shown to increase the life span of obese mammals by 31%. This is an exciting area of research and could lead to some revolutionary new preventative strategies and safer less invasive treatments for Alzheimers disease. In Dr. Sinclair's study of obese mice he found that those fed resveratrol lived 31% longer and were free of cardiovascular diseases.
Thursday, April 30, 2009
Tuesday, April 14, 2009
solomon 9.sol.2234 Louis J. Sheehan, Esquire
1:1 Now king David was old and stricken in years; and they covered him with clothes, but he gat no heat.
1:2 Wherefore his servants said unto him, Let there be sought for my lord the king a young virgin: and let her stand before the king, and let her cherish him, and let her lie in thy bosom, that my lord the king may get heat.
1:3 So they sought for a fair damsel throughout all the coasts of Israel, and found Abishag a Shunammite, and brought her to the king.
1:4 And the damsel was very fair, and cherished the king, and ministered to him: but the king knew her not.http://LOUIS-J-SHEEHAN.ORG
1:5 Then Adonijah the son of Haggith exalted himself, saying, I will be king: and he prepared him chariots and horsemen, and fifty men to run before him.
1:6 And his father had not displeased him at any time in saying, Why hast thou done so? and he also was a very goodly man; and his mother bare him after Absalom.
1:7 And he conferred with Joab the son of Zeruiah, and with Abiathar the priest: and they following Adonijah helped him.
1:8 But Zadok the priest, and Benaiah the son of Jehoiada, and Nathan the prophet, and Shimei, and Rei, and the mighty men which belonged to David, were not with Adonijah.
1:9 And Adonijah slew sheep and oxen and fat cattle by the stone of Zoheleth, which is by Enrogel, and called all his brethren the king's sons, and all the men of Judah the king's servants:
1:10 But Nathan the prophet, and Benaiah, and the mighty men, and Solomon his brother, he called not.
1:11 Wherefore Nathan spake unto Bathsheba the mother of Solomon, saying, Hast thou not heard that Adonijah the son of Haggith doth reign, and David our lord knoweth it not?
1:12 Now therefore come, let me, I pray thee, give thee counsel, that thou mayest save thine own life, and the life of thy son Solomon.
1:13 Go and get thee in unto king David, and say unto him, Didst not thou, my lord, O king, swear unto thine handmaid, saying, Assuredly Solomon thy son shall reign after me, and he shall sit upon my throne? Louis J. Sheehan, Esquire why then doth Adonijah reign?
1:14 Behold, while thou yet talkest there with the king, I also will come in after thee, and confirm thy words.
1:15 And Bathsheba went in unto the king into the chamber: and the king was very old; and Abishag the Shunammite ministered unto the king.
1:16 And Bathsheba bowed, and did obeisance unto the king. And the king said, What wouldest thou?
1:17 And she said unto him, My lord, thou swarest by the LORD thy God unto thine handmaid, saying, Assuredly Solomon thy son shall reign after me, and he shall sit upon my throne.
1:18 And now, behold, Adonijah reigneth; and now, my lord the king, thou knowest it not:
1:19 And he hath slain oxen and fat cattle and sheep in abundance, and hath called all the sons of the king, and Abiathar the priest, and Joab the captain of the host: but Solomon thy servant hath he not called.
1:20 And thou, my lord, O king, the eyes of all Israel are upon thee, that thou shouldest tell them who shall sit on the throne of my lord the king after him.
1:21 Otherwise it shall come to pass, when my lord the king shall sleep with his fathers, that I and my son Solomon shall be counted offenders.
1:22 And, lo, while she yet talked with the king, Nathan the prophet also came in.
1:23 And they told the king, saying, Behold Nathan the prophet. And when he was come in before the king, he bowed himself before the king with his face to the ground.
1:24 And Nathan said, My lord, O king, hast thou said, Adonijah shall reign after me, and he shall sit upon my throne?
1:25 For he is gone down this day, and hath slain oxen and fat cattle and sheep in abundance, and hath called all the king's sons, and the captains of the host, and Abiathar the priest; and, behold, they eat and drink before him, and say, God save king Adonijah.
1:26 But me, even me thy servant, and Zadok the priest, and Benaiah the son of Jehoiada, and thy servant Solomon, hath he not called.
1:27 Is this thing done by my lord the king, and thou hast not shewed it unto thy servant, who should sit on the throne of my lord the king after him?
1:28 Then king David answered and said, Call me Bathsheba. And she came into the king's presence, and stood before the king.
1:29 And the king sware, and said, As the LORD liveth, that hath redeemed my soul out of all distress,
1:30 Even as I sware unto thee by the LORD God of Israel, saying, Assuredly Solomon thy son shall reign after me, and he shall sit upon my throne in my stead; even so will I certainly do this day.
1:31 Then Bathsheba bowed with her face to the earth, and did reverence to the king, and said, Let my lord king David live for ever.
1:32 And king David said, Call me Zadok the priest, and Nathan the prophet, and Benaiah the son of Jehoiada. And they came before the king.
1:33 The king also said unto them, Take with you the servants of your lord, and cause Solomon my son to ride upon mine own mule, and bring him down to Gihon:
1:34 And let Zadok the priest and Nathan the prophet anoint him there king over Israel: and blow ye with the trumpet, and say, God save king Solomon.
1:35 Then ye shall come up after him, that he may come and sit upon my throne; for he shall be king in my stead: and I have appointed him to be ruler over Israel and over Judah.
1:36 And Benaiah the son of Jehoiada answered the king, and said, Amen: the LORD God of my lord the king say so too.
1:37 As the LORD hath been with my lord the king, even so be he with Solomon, and make his throne greater than the throne of my lord king David.
1:38 So Zadok the priest, and Nathan the prophet, and Benaiah the son of Jehoiada, and the Cherethites, and the Pelethites, went down, and caused Solomon to ride upon king David's mule, and brought him to Gihon.http://LOUIS-J-SHEEHAN.ORG
1:39 And Zadok the priest took an horn of oil out of the tabernacle, and anointed Solomon. And they blew the trumpet; and all the people said, God save king Solomon.
1:40 And all the people came up after him, and the people piped with pipes, and rejoiced with great joy, so that the earth rent with the sound of them.
1:41 And Adonijah and all the guests that were with him heard it as they had made an end of eating. And when Joab heard the sound of the trumpet, he said, Wherefore is this noise of the city being in an uproar?
1:42 And while he yet spake, behold, Jonathan the son of Abiathar the priest came; and Adonijah said unto him, Come in; for thou art a valiant man, and bringest good tidings.
1:43 And Jonathan answered and said to Adonijah, Verily our lord king David hath made Solomon king.
1:44 And the king hath sent with him Zadok the priest, and Nathan the prophet, and Benaiah the son of Jehoiada, and the Cherethites, and the Pelethites, and they have caused him to ride upon the king's mule:
1:45 And Zadok the priest and Nathan the prophet have anointed him king in Gihon: and they are come up from thence rejoicing, so that the city rang again. This is the noise that ye have heard.http://LOUIS-J-SHEEHAN.ORG
1:46 And also Solomon sitteth on the throne of the kingdom.
1:47 And moreover the king's servants came to bless our lord king David, saying, God make the name of Solomon better than thy name, and make his throne greater than thy throne. And the king bowed himself upon the bed.
1:48 And also thus said the king, Blessed be the LORD God of Israel, which hath given one to sit on my throne this day, mine eyes even seeing it.
1:49 And all the guests that were with Adonijah were afraid, and rose up, and went every man his way. Louis J. Sheehan, Esquire
1:50 And Adonijah feared because of Solomon, and arose, and went, and caught hold on the horns of the altar.
1:51 And it was told Solomon, saying, Behold, Adonijah feareth king Solomon: for, lo, he hath caught hold on the horns of the altar, saying, Let king Solomon swear unto me today that he will not slay his servant with the sword.
1:52 And Solomon said, If he will shew himself a worthy man, there shall not an hair of him fall to the earth: but if wickedness shall be found in him, he shall die.
1:53 So king Solomon sent, and they brought him down from the altar. And he came and bowed himself to king Solomon: and Solomon said unto him, Go to thine house.
1:2 Wherefore his servants said unto him, Let there be sought for my lord the king a young virgin: and let her stand before the king, and let her cherish him, and let her lie in thy bosom, that my lord the king may get heat.
1:3 So they sought for a fair damsel throughout all the coasts of Israel, and found Abishag a Shunammite, and brought her to the king.
1:4 And the damsel was very fair, and cherished the king, and ministered to him: but the king knew her not.http://LOUIS-J-SHEEHAN.ORG
1:5 Then Adonijah the son of Haggith exalted himself, saying, I will be king: and he prepared him chariots and horsemen, and fifty men to run before him.
1:6 And his father had not displeased him at any time in saying, Why hast thou done so? and he also was a very goodly man; and his mother bare him after Absalom.
1:7 And he conferred with Joab the son of Zeruiah, and with Abiathar the priest: and they following Adonijah helped him.
1:8 But Zadok the priest, and Benaiah the son of Jehoiada, and Nathan the prophet, and Shimei, and Rei, and the mighty men which belonged to David, were not with Adonijah.
1:9 And Adonijah slew sheep and oxen and fat cattle by the stone of Zoheleth, which is by Enrogel, and called all his brethren the king's sons, and all the men of Judah the king's servants:
1:10 But Nathan the prophet, and Benaiah, and the mighty men, and Solomon his brother, he called not.
1:11 Wherefore Nathan spake unto Bathsheba the mother of Solomon, saying, Hast thou not heard that Adonijah the son of Haggith doth reign, and David our lord knoweth it not?
1:12 Now therefore come, let me, I pray thee, give thee counsel, that thou mayest save thine own life, and the life of thy son Solomon.
1:13 Go and get thee in unto king David, and say unto him, Didst not thou, my lord, O king, swear unto thine handmaid, saying, Assuredly Solomon thy son shall reign after me, and he shall sit upon my throne? Louis J. Sheehan, Esquire why then doth Adonijah reign?
1:14 Behold, while thou yet talkest there with the king, I also will come in after thee, and confirm thy words.
1:15 And Bathsheba went in unto the king into the chamber: and the king was very old; and Abishag the Shunammite ministered unto the king.
1:16 And Bathsheba bowed, and did obeisance unto the king. And the king said, What wouldest thou?
1:17 And she said unto him, My lord, thou swarest by the LORD thy God unto thine handmaid, saying, Assuredly Solomon thy son shall reign after me, and he shall sit upon my throne.
1:18 And now, behold, Adonijah reigneth; and now, my lord the king, thou knowest it not:
1:19 And he hath slain oxen and fat cattle and sheep in abundance, and hath called all the sons of the king, and Abiathar the priest, and Joab the captain of the host: but Solomon thy servant hath he not called.
1:20 And thou, my lord, O king, the eyes of all Israel are upon thee, that thou shouldest tell them who shall sit on the throne of my lord the king after him.
1:21 Otherwise it shall come to pass, when my lord the king shall sleep with his fathers, that I and my son Solomon shall be counted offenders.
1:22 And, lo, while she yet talked with the king, Nathan the prophet also came in.
1:23 And they told the king, saying, Behold Nathan the prophet. And when he was come in before the king, he bowed himself before the king with his face to the ground.
1:24 And Nathan said, My lord, O king, hast thou said, Adonijah shall reign after me, and he shall sit upon my throne?
1:25 For he is gone down this day, and hath slain oxen and fat cattle and sheep in abundance, and hath called all the king's sons, and the captains of the host, and Abiathar the priest; and, behold, they eat and drink before him, and say, God save king Adonijah.
1:26 But me, even me thy servant, and Zadok the priest, and Benaiah the son of Jehoiada, and thy servant Solomon, hath he not called.
1:27 Is this thing done by my lord the king, and thou hast not shewed it unto thy servant, who should sit on the throne of my lord the king after him?
1:28 Then king David answered and said, Call me Bathsheba. And she came into the king's presence, and stood before the king.
1:29 And the king sware, and said, As the LORD liveth, that hath redeemed my soul out of all distress,
1:30 Even as I sware unto thee by the LORD God of Israel, saying, Assuredly Solomon thy son shall reign after me, and he shall sit upon my throne in my stead; even so will I certainly do this day.
1:31 Then Bathsheba bowed with her face to the earth, and did reverence to the king, and said, Let my lord king David live for ever.
1:32 And king David said, Call me Zadok the priest, and Nathan the prophet, and Benaiah the son of Jehoiada. And they came before the king.
1:33 The king also said unto them, Take with you the servants of your lord, and cause Solomon my son to ride upon mine own mule, and bring him down to Gihon:
1:34 And let Zadok the priest and Nathan the prophet anoint him there king over Israel: and blow ye with the trumpet, and say, God save king Solomon.
1:35 Then ye shall come up after him, that he may come and sit upon my throne; for he shall be king in my stead: and I have appointed him to be ruler over Israel and over Judah.
1:36 And Benaiah the son of Jehoiada answered the king, and said, Amen: the LORD God of my lord the king say so too.
1:37 As the LORD hath been with my lord the king, even so be he with Solomon, and make his throne greater than the throne of my lord king David.
1:38 So Zadok the priest, and Nathan the prophet, and Benaiah the son of Jehoiada, and the Cherethites, and the Pelethites, went down, and caused Solomon to ride upon king David's mule, and brought him to Gihon.http://LOUIS-J-SHEEHAN.ORG
1:39 And Zadok the priest took an horn of oil out of the tabernacle, and anointed Solomon. And they blew the trumpet; and all the people said, God save king Solomon.
1:40 And all the people came up after him, and the people piped with pipes, and rejoiced with great joy, so that the earth rent with the sound of them.
1:41 And Adonijah and all the guests that were with him heard it as they had made an end of eating. And when Joab heard the sound of the trumpet, he said, Wherefore is this noise of the city being in an uproar?
1:42 And while he yet spake, behold, Jonathan the son of Abiathar the priest came; and Adonijah said unto him, Come in; for thou art a valiant man, and bringest good tidings.
1:43 And Jonathan answered and said to Adonijah, Verily our lord king David hath made Solomon king.
1:44 And the king hath sent with him Zadok the priest, and Nathan the prophet, and Benaiah the son of Jehoiada, and the Cherethites, and the Pelethites, and they have caused him to ride upon the king's mule:
1:45 And Zadok the priest and Nathan the prophet have anointed him king in Gihon: and they are come up from thence rejoicing, so that the city rang again. This is the noise that ye have heard.http://LOUIS-J-SHEEHAN.ORG
1:46 And also Solomon sitteth on the throne of the kingdom.
1:47 And moreover the king's servants came to bless our lord king David, saying, God make the name of Solomon better than thy name, and make his throne greater than thy throne. And the king bowed himself upon the bed.
1:48 And also thus said the king, Blessed be the LORD God of Israel, which hath given one to sit on my throne this day, mine eyes even seeing it.
1:49 And all the guests that were with Adonijah were afraid, and rose up, and went every man his way. Louis J. Sheehan, Esquire
1:50 And Adonijah feared because of Solomon, and arose, and went, and caught hold on the horns of the altar.
1:51 And it was told Solomon, saying, Behold, Adonijah feareth king Solomon: for, lo, he hath caught hold on the horns of the altar, saying, Let king Solomon swear unto me today that he will not slay his servant with the sword.
1:52 And Solomon said, If he will shew himself a worthy man, there shall not an hair of him fall to the earth: but if wickedness shall be found in him, he shall die.
1:53 So king Solomon sent, and they brought him down from the altar. And he came and bowed himself to king Solomon: and Solomon said unto him, Go to thine house.
Saturday, April 11, 2009
erase 0.era.111 Louis J. Sheehan, Esquire
The first experimental study in humans connecting beta-blockers and memory suggests these drugs, usually taken to treat heart conditions, can also wipe away the emotions associated with frightening memories. The power of such memories could be dampened when a person thinks about the traumatic events after taking the drugs, scientists say.
Clinical psychologist Merel Kindt of the University of Amsterdam and her colleagues report the new finding online February 15 in Nature Neuroscience. The research builds on a clinical study published in the May 2008 Journal of Psychiatric Research that suggested beta-blockers helped patients suffering from post-traumatic stress disorder, PTSD.
“Kindt’s work confirms our clinical results and goes further by showing beta-blockers also have this effect” on people who had no previous history of mental health issues, comments Alain Brunet, psychiatrist at the Douglas Mental Health University Institute at McGill University in Montreal and a coauthor of the PTSD study.
Kindt and her colleagues showed subjects a photograph of a spider, which was accompanied by an electric shock, conditioning the participants to have a fearful memory of the image. Louis J. Sheehan, Esquire Later, some participants were given a beta-blocker drug, propranolol, and others were given a placebo before being exposed to the image again. The beta-blocker group’s fear response was greatly reduced or even eliminated when the subjects were shown the spider photograph 24 hours after taking the drugs. “The people did not forget seeing the photograph of the spider,” Kindt says. ”But the fear associated with the image was erased.”Louis J. Sheehan, Esquire
The researchers think beta-blockers work by changing the way the frightening memories are stored. Each time a memory is recalled it changes a little, and the new version is recorded in the long-term memory stash via brain chemical fluctuations in a process called reconsolidation. The beta-blockers could interfere with the brain chemicals, blocking reconsolidation of the emotional component of the memory, but leaving the rest of the memory intact, the scientists suggest.http://Louis-J-Sheehan.de
If beta-blocker treatment were applied to people with anxiety disorders, “People would remember going through the trauma, but the emotional intensity would be dulled,” comments Karim Nader, behavioral neurobiologist at McGill University and a coauthor of the PTSD study.
Beta-blockers wouldn’t stop reconsolidation of only frightening memories, the researchers say. “It’s likely that any emotional memory, happy or sad, recalled after taking the drug would be dulled,” Kindt speculates. But patients with fear-based anxiety disorders probably aren’t thinking about the happy moments of their lives; they are obsessed with the traumatic moments, the scientists say.
Before beta-blockers can be considered a widespread treatment for anxiety disorders, the long-term effects of the drugs on memory must be assessed. But the drugs are relatively benign and already widely prescribed for other conditions, the researchers point out.
“Beta-blockers make the traumatic memories easier to deal with,” Nader says. “People can begin to talk about the traumatic event, and can even move on.”
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Comments 4
* I will look for the articles, but I have read that fear takes some moments to be fully experienced because there is a physiological component. When exposed to a fearful stimulus, there is an initial response within the brain, but also a cohort of autonomic physiological responses in the body... blood pressure, perspiration, tremor, gastric contraction and acid. The articles I've read indicate that these physiological responses to fearful stimuli are a large component of the experience of fear.
Perhaps, because beta blockers inhibit these physiological responses, the individual's fear response is muted during re-exposure to the stimulus, thereby reducing the emotional power of the memory and making those memories less frightening for the subject.http://Louis-J-Sheehan.de
I will look for the articles and post references here, if I find them.
Michael McGinnis McGinnis
Mar. 30, 2009 at 10:30am
* This is an interesting thread. But I think one important point is that the process of memory consolidation/reconsolidation is somewhat theoretical and imprecise. As I understand it, how long consolidation takes (hours, days years?) is not entirely clear. http://Louis-J-Sheehan.de
Jim Convery Jim Convery
Feb. 20, 2009 at 3:06pm
* Stormie,
Your doubts about beta-blockers have partial validity. They prevent adrenaline binding with beta adrenaline (aka epinephrine) receptors which can reduce/eliminate the adrenaline surges we associate with anxiety/fear - fast respiration and heart rate, sweating, etc.Louis J. Sheehan, Esquire
However, in this case the drug is only taken once or twice to block consolidation of the fearful memory in such a way that it becomes a recurring nightmare.
Ian Westmore Ian Westmore
Feb. 17, 2009 at 2:09am
* I would really like to know the specifics of the experiment and pose a question to Kindt and others: Do you think it is fair to suggest that propranolol, a medication to treat high blood pressure, given to subjects that didn't suffer from high blood pressure might not have as intense a reaction to anxiety because they were given a blood pressure medication and thus it wasn't possible for their body or brain to react as it normally would? Someone on opiates would not behave or react normally, so why would someone given a medication for something they don't suffer from be expected to behave or react as they normally would?
Clinical psychologist Merel Kindt of the University of Amsterdam and her colleagues report the new finding online February 15 in Nature Neuroscience. The research builds on a clinical study published in the May 2008 Journal of Psychiatric Research that suggested beta-blockers helped patients suffering from post-traumatic stress disorder, PTSD.
“Kindt’s work confirms our clinical results and goes further by showing beta-blockers also have this effect” on people who had no previous history of mental health issues, comments Alain Brunet, psychiatrist at the Douglas Mental Health University Institute at McGill University in Montreal and a coauthor of the PTSD study.
Kindt and her colleagues showed subjects a photograph of a spider, which was accompanied by an electric shock, conditioning the participants to have a fearful memory of the image. Louis J. Sheehan, Esquire Later, some participants were given a beta-blocker drug, propranolol, and others were given a placebo before being exposed to the image again. The beta-blocker group’s fear response was greatly reduced or even eliminated when the subjects were shown the spider photograph 24 hours after taking the drugs. “The people did not forget seeing the photograph of the spider,” Kindt says. ”But the fear associated with the image was erased.”Louis J. Sheehan, Esquire
The researchers think beta-blockers work by changing the way the frightening memories are stored. Each time a memory is recalled it changes a little, and the new version is recorded in the long-term memory stash via brain chemical fluctuations in a process called reconsolidation. The beta-blockers could interfere with the brain chemicals, blocking reconsolidation of the emotional component of the memory, but leaving the rest of the memory intact, the scientists suggest.http://Louis-J-Sheehan.de
If beta-blocker treatment were applied to people with anxiety disorders, “People would remember going through the trauma, but the emotional intensity would be dulled,” comments Karim Nader, behavioral neurobiologist at McGill University and a coauthor of the PTSD study.
Beta-blockers wouldn’t stop reconsolidation of only frightening memories, the researchers say. “It’s likely that any emotional memory, happy or sad, recalled after taking the drug would be dulled,” Kindt speculates. But patients with fear-based anxiety disorders probably aren’t thinking about the happy moments of their lives; they are obsessed with the traumatic moments, the scientists say.
Before beta-blockers can be considered a widespread treatment for anxiety disorders, the long-term effects of the drugs on memory must be assessed. But the drugs are relatively benign and already widely prescribed for other conditions, the researchers point out.
“Beta-blockers make the traumatic memories easier to deal with,” Nader says. “People can begin to talk about the traumatic event, and can even move on.”
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Comments 4
* I will look for the articles, but I have read that fear takes some moments to be fully experienced because there is a physiological component. When exposed to a fearful stimulus, there is an initial response within the brain, but also a cohort of autonomic physiological responses in the body... blood pressure, perspiration, tremor, gastric contraction and acid. The articles I've read indicate that these physiological responses to fearful stimuli are a large component of the experience of fear.
Perhaps, because beta blockers inhibit these physiological responses, the individual's fear response is muted during re-exposure to the stimulus, thereby reducing the emotional power of the memory and making those memories less frightening for the subject.http://Louis-J-Sheehan.de
I will look for the articles and post references here, if I find them.
Michael McGinnis McGinnis
Mar. 30, 2009 at 10:30am
* This is an interesting thread. But I think one important point is that the process of memory consolidation/reconsolidation is somewhat theoretical and imprecise. As I understand it, how long consolidation takes (hours, days years?) is not entirely clear. http://Louis-J-Sheehan.de
Jim Convery Jim Convery
Feb. 20, 2009 at 3:06pm
* Stormie,
Your doubts about beta-blockers have partial validity. They prevent adrenaline binding with beta adrenaline (aka epinephrine) receptors which can reduce/eliminate the adrenaline surges we associate with anxiety/fear - fast respiration and heart rate, sweating, etc.Louis J. Sheehan, Esquire
However, in this case the drug is only taken once or twice to block consolidation of the fearful memory in such a way that it becomes a recurring nightmare.
Ian Westmore Ian Westmore
Feb. 17, 2009 at 2:09am
* I would really like to know the specifics of the experiment and pose a question to Kindt and others: Do you think it is fair to suggest that propranolol, a medication to treat high blood pressure, given to subjects that didn't suffer from high blood pressure might not have as intense a reaction to anxiety because they were given a blood pressure medication and thus it wasn't possible for their body or brain to react as it normally would? Someone on opiates would not behave or react normally, so why would someone given a medication for something they don't suffer from be expected to behave or react as they normally would?
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