The Medulla Oblongata

Protruding behind the pons (Fig. 14), the medulla oblongata tapers smoothly into the spinal cord. Like many regions of the CNS (see locus ceruleus), it is important out of proportion to its size. No bigger around than the last part of a little finger, it is vital. Even slight injury to it can swiftly lead to devastating or fatal consequences: hemianesthesia, hemi- or diple-gia, and respiratory arrest. Through the medulla oblongata run all of the long ascending and descending tracts that connect the brain with the spinal cord and permit their interactions. In it are neuronal clusters of the lowermost five cranial nerves (Table II) and other nuclei that regulate breathing, heart rate, swallowing, caliber of small blood vessels, and indirectly blood pressure, waking, sleeping, and other vital functions. Some medullary neurons, like those of the brain stem serotonergic system, elicit profound effects by their neurotransmitters and through pervasive connections on general levels of activity elsewhere in the neuraxis. Consciousness and alertness depend on their upward influences, and spinal reflexes of posture, locomotion, and visceration rely on their downward effects.

Conquering Fear In The 21th Century

Conquering Fear In The 21th Century

The Ultimate Guide To Overcoming Fear And Getting Breakthroughs. Fear is without doubt among the strongest and most influential emotional responses we have, and it may act as both a protective and destructive force depending upon the situation.

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