The hemispheric lateralization of speech processing depends on what "speech" is: a hierarchical perspective

Brain lateralization refers to the division of mental processes and functions between the two hemispheres of the brain, a phenomenon that optimizes neural efficiency and underpins complex abilities in humans. This specialization allows each hemisphere to perform tasks where it has a comparative advantage, facilitating more refined cognitive capabilities across different domains.

Language is a system of communication that allows the expression of thoughts, ideas, and feelings. The brain processes language in both hemispheres.
Language formation and comprehension take place in the dominant hemisphere. The dominant hemisphere is responsible for understanding the meaning of spoken, written, or sign language, as well as the ability to communicate. For most people, the left hemisphere is the dominant one. The right hemisphere, then, gives tone and emotional context to the...

The human brain, a complex organ, is functionally divided into two cerebral hemispheres—left and right. These hemispheres are interconnected by a structure of paramount importance, the corpus callosum. This substantial bundle of neural fibers is not just a bridge between the hemispheres but a crucial element for the brain's comprehensive functioning. It enables efficient communication between the two hemispheres, allowing each side of the brain to control and receive sensory and motor...

The cerebral cortex, a critical structure of the brain, is intricately divided into two hemispheres, each consisting of four distinct lobes: occipital, temporal, frontal, and parietal. These lobes function cooperatively to regulate various cognitive and sensory functions, forming the basis of our complex neural capabilities.
Frontal lobe
The frontal lobes, located behind the forehead, are the command center of our brain, controlling personality, intelligence, and voluntary muscle movements.