The Nikon MicroscopyU confocal microscopy image gallery was created with a PCM-2000 confocal scanning system interfaced to a Nikon Eclipse E600 upright microscope. Images were recorded in successive z-axis serial sections with C-Imaging Systems software with excitation illumination provided by an argon-ion and/or a helium-neon laser.

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The mystique of the brain intrigues modern biologists and psychologists even as it did the philosophers of ancient times. Brain function is so strongly associated with what it means to be alive and human that the cessation of brain activity is a clinical and legal criterion of death, even when other organs of the body are still functioning.

With its hundreds of neuronal pools, its 35 billion neurons, and trillions of synapses, the brain performs sophisticated tasks beyond our present understanding. Still, all of our mental functions, no matter how complex, are ultimately based on the cellular activities that can be explored through confocal microscopy.

The average brain weighs about 3.5 lbs in men and slightly less in women. Body size, not intelligence determines the human brain size. Consider that the Neanderthals had much larger brains than modern humans.

The brain can be divided into three major portions -- the cerebrum, cerebellum, and brain stem, with the cerebrum making up about 83 percent of the brain's volume divided into two cerebral hemispheres. Gyri, thick folds or "mountains," are separated in the brain's topography by "valleys" or shallow grooves called sulci. The cerebral cortex (outer layer of gray matter) functions to allow us to perceive, communicate, remember, understand, appreciate and initiate voluntary movements -- all of which compose conscious behavior. The parietal lobe of the cerebral cortex is largely concerned with the integration of sensory information with the exception of hearing, smell and vision (which occur elsewhere in the brain).

Along the post-central gyrus is the primary somatosensory cortex; that is, the area of the brain that receives information from the general sensory receptors and allows us to identify which part of our body is being stimulated. This accounts for spatial discrimination provided by the processing by the pyramidal neurons (multipolar cells similar to spinal cord cells) that compose the post-central gyrus.

Minamata disease, the debilitating syndrome described for Japanese fishermen with methyl mercury poisoning, attacks the nervous system with mercury deposits viewable in stained sections of the post-central gyrus. Unusual to Western cultures, sparaganosis, the human parasitic disease associated with the consumption or contact with reptiles and amphibians, leaves tapeworm larva in parts of the brain including the post-central gyrus, leading to serious, sometimes fatal illness.