European Stars And Stripes (Newspaper) - June 21, 1986, Darmstadt, Hesse Fng quest to link brain to mind the exercise of will. The research seems to Bland common sense on is head the Ordinary understanding of the sequence involved in a simple decision is. Firs one decides Ihen the mental decision leads the brain to trigger the action. Wrong according to findings by Benjamin libel a Neur physiologist Al the University of California at san Francisco. His research reported in Tho current Issue of the behavioural and brain sciences shows that appreciable brain actively precedes All voluntary acts. The activity nol Only seems to trigger the ads bul mos surprising it also precedes 1ho instant Al which a person decides to act in other words the sequence is brain a Lively followed by Tho conscious decision to act. Followed by the act in libel s study he volunteers brain activity was measured As they spontaneously moved a Finger. The timing of the decision to act was made by to volunteers noting the position of a revolving spot at the moment they became aware of Tho intent to move the Finger. Tho brain activity began on average 350 milliseconds or about a third of a second before the volunteers noted the decision to move the Finger. The Finger actually moved about 150 milliseconds after thai. This in libel s widely debated interpretation moans Hal the brain actually decides for the mind rather than Iho brain executing some conscious decision the person makes. Whal most people think of As free will in his View is actually an illusion occurring after the brain has made a decision to act. However libel has also found there is time to cancel the decision during the one tenth to two tenths of a second Between the person s awareness of intent and the action i sell. It is in the mind s ability to veto the brain s decision that tree will resides in his View a conclusion that has been greeted with scepticism from some philosophers who View his Dala As a trivial base Foi drawing grand conclusions Evan among psychologists. Libel s research is seen As a Bare beginning in tracing the brain s role in intention a mental act that pervades All human activity. For some researchers the Libet studies Are not As inner casting for whal they suggest about free will As what they imply about impulse and self control in related work researchers Are socking to find Oul whether the brain sends a signal on whether an action about to be Laken will be Correct or incorrect. They have Lound a signal that seems to precede a mistake such As pushing Iho wrong Button or reaching for the wrong utensil. Emmanuel Donchin Al Tho University of Illinois has been usog a computerized brain measure called i tie evoked potential to search just such a brain Signa Luro Hal errors Are Alibi. To be made if a reliable brain indicator can to found it might to possible for example to Monitor the brain of a Jel Pilot and signal him just before he is Aboul to make a mistake. When a person makes a simple error such As moving the wrong hand there is train a Lively present for both the Correct and Tho incorrect response according to research Donchin and his colleagues reported in a recent Issue of the journal of experimental psychology in Donchin s research the brain activity of volunteers was monitored while icy squeezed one of two bulbs held in each hand in response to letters flashed before them when they made an error the Correct and incorrect responses seemed to compete in the brain for a fraction of a second before the error was actually made the simplicity of Donchin s and Libot s research is typical of the new approach to studying the brain and mind. The connections Between the brain and mind Are so complicated that for now the research has been Able to examine Only the most elementary mental tasks in contrast much of the earlier work connecting mind and brain locus cd on finding specific areas in the brain that seem Lobo the site for particular manual functions such As speech. The search for localization is now seen As Foo narrow. It is too simple to see a Given place in the brain As where a mental acl occurs said Stephen Kosslyn. A cognitive psychologist at Harvard the new understanding is that specific networks of cells distributed throughout the brain Are highly involved in each component of a mental act thus he and other cognitive psychologists Are re examining the very categories they use to describe the mind such terms As they say arc simply too vague and Sloppy to be useful. For that reason. Iheson scientists prefer to look at Ever smaller connections Between the brain and us Houghl perception and behaviour the everyday common sense categories Are the wrong Way to describe whal happens at the level of brain activity said David Rumelhart a cognitive psychologist at the University of California Al san Diego we be had to ask an entirely now question How can mental events grow out of a system like the brain ii forces us to come up with biologically plausible models of the in the brain the Basic unit Are assemblies of cells in Tho mind they Are the smallest elements of menial activity according to his theory. In parallel Dis Tab used processing Mit Pressa new Book about the theory Rumelhart and John Mcclelland propose thai what is stored in memory is not specific facts or events tout rather the relationships Between the various aspects of those facts or events As they Are encoded in groupings of neuronal cells or pal terns of Celt activity memory then is not so much a copy of experience As the storage of the connections Between aspects of experience. A this View learning entails mastering the proper strengths of the Connexions Between them knowledge accumulates by the progressive association of these Cone Lions not by isolated impressions lists find surprises .,.human biological clock is sending Wake up signals. Some of these Are Houghl make the heart muscle More excitable. At University of Minnesota doctors have found thai optimal response to cancer drugs and minimum Side a flecks can be achieved in patients with breast cancer by careful attention to the individual s biological clock. Human growth hormone is produced mainly in one Spurl during that night. Production of the important hormone cortisol is far higher at night than in Iho daytime although the difference is not As Sharp As with growth hormone Normal excretion of potassium is live limes As great at night As in the morning. The bronchial air passages in some asthma patients have been found to constrict dangerously in the Early morning. In Many animal experiments it has been found that a Poison can be tar deadlier at one time of Day. Ii Short Are biological clocks they must actually exist somewhere end scientist have devoted much Effort to finding them. One that appears to be of great importance has been identified in recant years. This is a Small Region of the Forward part of the brain called the nuclei. This Region appears Olhava great influence in the body particularly Over the sleep Wake Cycle. Or. Martin c. Moore Ede of Harvard medical school says Allol the necessary criteria to prove the role of the nuclei have been satisfied. Ii the nuclei Are destroyed the rhythm disappears. Drugs of telling the nuclei distort the timing. The clock can still unction Whan transplanted of even when sliced up and observed on a Laboratory dish. June 21, 1986 cases have been authenticated in which a patient s sleep behaviour was grossly disc oiled by a tumor in Hal part of the brain. A much More specialized pacemaker has been known for Many years the pacemaker of the heart s sino atrial Node that governs the pulsing of the heart muscle. But Moore Ede says there appear to be other pacemakers As Well. Even when their Supra Miasmatic nuclei have been destroyed animals that Are fed regularly at a Standard time can predict with remarkable precision just when the keeper will bring their daily meal. Indeed his kind of predictive behaviour is believed to be one of the major functions of biological clocks in nature to warn the individual in Advance when to get up when to sleep when nun i for food. There is is even a logical Benefit in having multiple pacemakers. They coordinate and separate different functions that need to be kept in proper sequence. It is a very Active Field. There is a lot going on said Moore Ede of Chron biology research in general. His own studies Are focussed on the diurnal sleep Wake Cycle. These studies have widespread practical relevance ranging from duty watches on nuclear submarines and air traffic control towers to the Industrial workers who Man changing shifts in 24-hour factories. Many modern Industrial processes need to continue Day and night. An estimated 21 million americans Are already employed in shift work to serve the 24-hour appetites of the machines and computers. The stars and stripes Page 15
