What Is the Subiculum?

The subiculum is a fundamental area of the brain. The precise role of this region was not entirely understood as of 2011 because of a lack of comprehensive and conclusive research. It is one part of what is known as the hippocampal formation, which is a compound structure in the brain that assists with memory, spatial navigation and attention control. This portion of the hippocampal formation possesses both functional and electrophysiological properties, but the subiculum and the nature of its functions and effects have remained a mystery in many ways. Some researchers have argued that this structure is one of the most inferior among the hippocampal formation, and others believe that it is under-researched and that its potential effects on brain and human functioning might be significant.

As part of the hippocampal formation, this structure has been determined to have an influence on various areas of brain activity. The cells in the subiculum each move through periods of activity and inactivity. The bursting and spiking of electrons in these cells is one of the major electrophysiological properties of this structure. Each active period of spiking in every cell begins with bursts and then moves toward single spikes.

Studies in both rats and humans have been performed to determine the precise role of bursting and spiking in the input and output processes of the subiculum, though no consensus has been reached on many of the functions and roles of this structure. There are numerous questions regarding the electrophysiological, pharmacological, anatomical and other aspects of this structure. This is especially true in cases in which variations in the structure of the subiculum exist and might affect certain areas of human health and functioning.

Researchers have observed a link between mood disorders, schizophrenia and abnormalities of the subiculum. In these studies, postmortem investigations revealed that a majority of the subjects who suffered from schizophrenia also possessed structural abnormalities within the subiculum. Although a connection between these conditions is understood to exist, the final evidence remains inconclusive, given the variety of other factors — such as family history, long-term institutionalization and exposure to specific drug groups — that might affect the results of studies.

This region of the hippocampal formation is believed to be a contributor to some instances of epilepsy in humans. As with most studies relating to the effects that abnormalities within this structure might have on human functioning, however, this connection requires further investigation before medical or corrective applications can be aggressively pursued. This structure is also believed to have an effect on the likelihood for the development of drug addiction in humans. The subiculum also might take part in the brain’s ability to retain information that is required for reasoning, learning and comprehension, as well as many other aspects of working memory.