… wenn man’s positiv sehen will. Diese Meldung macht heute die Runde:
Memory, speed of thinking and other cognitive abilities get worse over time with marijuana use, according to a new study published in the March 14, 2006, issue of Neurology, the scientific journal of the American Academy of Neurology.
The study found that frequent marijuana users performed worse than non-users on tests of cognitive abilities, including divided attention (ability to pay attention to more than one stimulus at a time) and verbal fluency (number of words generated within a time limit). Those who had used marijuana for 10 years or more had more problems with their thinking abilities than those who had used marijuana for five to 10 years. All of the marijuana users were heavy users, which was defined as smoking four or more joints per week.
„We found that the longer people used marijuana, the more deterioration they had in these cognitive abilities, especially in the ability to learn and remember new information,“ said study author Lambros Messinis, PhD, of the Department of Neurology of the University Hospital of Patras in Patras, Greece. „In several areas, their abilities were significant enough to be considered impaired, with more impairment in the longer-term users than the shorter-term users.“ (…) In a test where participants needed to remember a list of words that had been read to them earlier, the non-users remembered an average of 12 out of 15 words, the shorter-term users remembered an average of nine words and the long-term users remembered an average of seven words.
(Max Planck Gesellschaft) Warum verstehen wir Menschen komplizierte Sätze und unsere nächsten Verwandten – die Affen – hingegen nur einzelne Worte? Nun haben Wissenschaftler des Leipziger Max-Planck-Instituts für Kognitions- und Neurowissenschaften herausgefunden, dass im menschlichen Gehirn zwei Hirnareale für verschiedene Verarbeitungsleistungen der Sprache zuständig sind. Sie stellten fest, dass einfache Sprachstrukturen in einem evolutionär älteren Hirnareal verarbeitet werden, über das auch Affen verfügen. Komplizierte Strukturen jedoch aktivieren Prozesse in einem entwicklungsgeschichtlich jüngeren Hirnareal, das nur höherentwickelte Spezies (Mensch) besitzen. Diese Befunde liefern einen wichtigen Baustein zum Verstehen des menschlichen Sprachvermögens (PNAS, 6. Februar 2006).
Aus der Abteilung „Das kenn ich doch von irgendwo…“
(The Reporter – University of Leeds Newsletter) Many of us have experienced déjà vu – the unsettling sensation of knowing that a situation could not have been experienced, combined with the feeling that it has. It is usually so fleeting that psychologists have until recently thought it impossible to study. But for some people, the feeling of having been there before is a persistent sensation, making every day a ‘Groundhog Day’. Psychologists from Leeds’ memory group are working with sufferers of chronic déjà vu on the world’s first study of the condition.
Dr Chris Moulin first encountered chronic déjà vu sufferers at a memory clinic. “We had a peculiar referral from a man who said there was no point visiting the clinic because he’d already been there, although this would have been impossible.” The patient not only genuinely believed he had met Dr Moulin before, he gave specific details about the times and places of these ‘remembered’ meetings.
Déjà vu has developed to such an extent that he had stopped watching TV – even the news – because it seemed to be a repeat, and even believed he could hear the same bird singing the same song in the same tree every time he went out. Chronic déjà vu sufferers are not only overwhelmed by a sense of familiarity for new experiences, they can provide plausible and complex justifications to support this. “When this particular patient’s wife asked what was going to happen next on a TV programme he’d claimed to have already seen, he said ‘how should I know? I have a memory problem!’” Dr Moulin said.
Moulin führt übrigens auch einen Blog.