Health Scan: Hebrew University researchers have more than a clue how conscious information processing by the brain is different from unconscious processing.
By JUDY SIEGEL-ITZKOVICHBurnt trees after the Carmel Fire 311 (R)(photo credit: Reuters)
Although the burnt sections of the Carmel Forest, that was devastated by the country’s worst-ever wildfire a year ago, are beginning to show green signs of life, the health of firefighters and policemen continue to show effects from the tragic event that killed 44 people.Researchers at the University of Haifa’s School of Public Health are carrying out a health study of those who fought the fire and tried to rescue victims.A total of 204 firefighters and 83 police officers from throughout the country were located and interviewed about their symptoms during and after the conflagration, exposure to smoke and other hazards.So far, the researchers have found that 87 percent of participants had at least one symptom during rescue work; the most common complaint was eye irritation, with 77% reporting on it and 71% mentioning fatigue. Twenty-seven percent of participants reported that at least one symptom continued in the months after the fire. More than 80% of the firemen and 35% of police wore respiratory protection while responding to the fire; the most common reasons cited for not using a respirator were that one was not available (34%) or that the wind was blowing the smoke in the opposite direction. The firefighters worked for an average 18.4 hours with no sleep.More than half said their personal safety was moderately to severely at risk, and 49% felt at moderate to severe risk of losing their lives. A quarter of participants (17% of firefighters and 44% of police) reported at least one acute stress-related symptom such as persistent difficulty sleeping, intrusive thoughts and avoidance behaviors after the fire. Police were 3.5 times more likely to report symptoms of post-traumatic stress disorder than firefighters.The Haifa researchers will continue to follow those they interviewed to ensure there are no lasting health effects.Initial start-up funding of the “Carmel Cohort” study came from the Environment and Health Fund. Dr. Eric Amster from the Harvard School of Public Health, who was the lead investigator, is currently a a Fulbright postdoctoral researcher in Haifa.CONSCIOUS INFO PROCESSINGHow conscious information processing by the brain is different from unconscious processing has long puzzled psychologists, philosophers and neurobiologists. Now Hebrew University researchers have more than a clue and published their findings in a recent issue of the journal Psychological Science.
Another question is whether there is any role for conscious awareness in information processing or is it just a by-product, like the steam from the chimney of a train engine, which is significant but has no functional role. The study was headed by Prof. Leon Deouell from its Center for Brain Sciences and Prof. Dominique Lamy from the psychology department and conducted by TAU research student Liad Mudirk and HU research student Assaf Breska.
People are not consciously aware of most of the input of their sensory systems. Yet subjectively, conscious awareness dominates our mental activity.“One of the dominant theories in cognitive sciences and psychology posits that parts of the information perceived without awareness may be processed to a certain extent,” said Deouell. “Yet to bind the different parts of a complex input into something meaningful and coherent requires conscious awareness. To test this theory, the research team ran a study in which they presented participants with pictures of natural scenes including some human action, like a picture of basketball players jumping to reach a ball. In other tests, the same scenes were presented – except that the central object was replaced by an unlikely object such as a watermelon instead of a basketball. The participants viewed the pictures through a mirror stereoscope, a simple device that allowed the research team to present the pictures to only one eye.“At the same time, the other eye viewed rapidly flickering patterns of colors which drew the subjects’ attention so they were not aware for many seconds that anything was [being] presented to their other eye. This allowed the researchers to measure how long it takes normal and unusual scenes to ‘win the competition’ against the flickering pattern and break into awareness.“We found that participants became aware of the unusual scenes earlier than to the usual scenes,” said Deouell. “The conclusion was that even before the participants were aware of the existence of the picture, the semantic relationships between parts of the scene were interpreted.”The study shows that, counter to previous theories, integration is not the prerogative of conscious awareness but is achieved even without awareness.The study expands the realm of unaware processes, yet shows that conscious awareness is not a meaningless luxury – it allows us to deal with novel and unexpected situations.
