The frontal lobes are areas at the front of each cerebral hemisphere in front of the primary motor cortex and the parietal lobes and in front of and above the temporal lobes on the sides of the head. If you look at the brain from the side, it looks like a boxing glove with the thumbs pointing in the direction of the gaze and the palm of the hand facing downwards. The bent fingers are where the frontal lobe would be. The frontal lobe plays a crucial role in rational decision-making, emotional regulation, moral judgment and in shaping our personality.
Decision-Making
Different parts of the frontal lobe are involved in making different kinds of decisions, reports cognitive scientist David Badre of Brown University. Badre and his team examined stroke victims who performed decision-making tasks ranging from particular to general. The scientists found that the most general decisions, such as deciding to have a sandwich, take place in front part of the frontal lobe, whereas particular decisions, such as choosing a series of movements that make a sandwich, take place in the back of the frontal lobe, the area closer to the primary motor complex.
Working Memory
Working memory is the ability to keep information in your head for a short amount of time, for example, information that's available when you carry over in subtraction, look up and dial a phone number or recall an image of your friend. Working memory is associated with a transient synchronization of neurons in a complex cortical network of frontal, parietal, visual and temporal brain areas, reports a research team in the April 2010 issue of "PNAS." While information is dispersed in this complex network, manipulation of the information is more localized. For example, paying attention to a piece of information requires frontoparietal regions, the researchers say.
Narcissism
The frontal lobe is also the center for personality and self-knowledge. The more we rely on our frontal lobes, the more critical we will be of ourselves, report Jennifer Beer, a University of Texas at Austin researcher. Conversely, the less we rely on our frontal lobes, the more we will like ourselves and inflate our good qualities. Beer scanned the brains of 20 subjects while they answered questions about how they compared to their peers in terms of traits such as modesty, likability and narrow-mindedness. The subjects who didn't rely much on their orbitofrontal cortex, the region associated with decision-making and reasoning, viewed themselves in a very positive light, Beer reports.
Moral Judgments
Emotional regulation is another important function of the frontal lobe. Antonio Damasio, a leading expert in emotional regulation, carried out a number of studies on people with lesions to the ventromedial prefrontal cortex, or VMPC. In one of his studies, he found that patients with VMPC lesions don't care about long-term planning as long as they get an immediate reward. In a more recent study, published in the March 2010 issue of "Neuron," Damasio and his team found that patients with VMPC lesions do not make normal moral judgments. They will treat acts without negative outcomes as morally permissible regardless of whether they were accidents or attempted murders.
Psychopathic Behavior
Given the importance of the frontal lobe in rational decision-making, emotional regulation and moral judgment, it is not surprising to find that psychopaths have dysfunctional frontal lobes. The finding came from a study published in the May 2010 issue of "Cortex." Haifa neuroscientist Simone Shamay-Tsoory and colleagues compared psychopaths to individuals with frontal lobe damage and found a striking resemblance in the brain patterns of the two groups. The findings confirm the existing hypothesis that psychopaths cannot empathize despite having other good reasoning skills. These two components constituting the so-called "theory of mind" are independent systems, and one can be damaged while the other is intact.
References
- Science Daily: Evidence Appears To Show How And Where Brain's Frontal Lobe Works
- Science Daily: Human Working Memory Is Based on Dynamic Interaction Networks in the Brain
- Science Daily: Brain Activity Levels Affect Self-Perception
- Science Daily: Emotions Key to Judging Others
- Science Daily: An Underlying Cause for Psychopathic Behavior?
