basaldendritit

Basaldendritit are the dendritic branches that extend from the base of a neuron’s soma. In many excitatory neurons of the cerebral cortex and hippocampus, basal dendrites form a dense, relatively compact arbor close to the cell body, contrasting with a single apical dendrite that rises toward the cortical surface. The term basaldendritit is the Finnish name for these structures.

Structure and connections. Basal dendrites typically consist of several primary branches that further subdivide into smaller segments. They are rich in dendritic spines and preferentially receive excitatory synapses from local circuits, thalamic inputs, and neighboring neurons. Their placement near the soma supports the integration of inputs that influence the neuron's output, while apical dendrites often collect inputs from more distant or higher-order areas.

Function and properties. Basal dendrites are sites of synaptic integration and can support active electrical properties, including local dendritic spikes and calcium transients that contribute to synaptic plasticity such as long-term potentiation and long-term depression. The proximal location of basal dendrites to the soma means their synaptic input has a strong influence on whether the neuron fires.

Variations and significance. The size, branching pattern, and spine density of basal dendrites vary across neuron types and brain regions. Changes in basal dendrite morphology and spine density have been observed in various neurological and psychiatric conditions, highlighting their role in information processing, learning, and memory.