This post may be helpful to those of you who know children or adults who struggle with finding the "right" word. In the old days, a simplistic view of the brain held that the left hemisphere was the location for language. Now we have a more complex understanding of language - and the right hemisphere has its own distinctive role in understanding words - and its strengths are more contextual and associational rather than direct and semantic.
In the figure below, look at a schematic diagram of a patient who underwent a partial corpus callosectomy for seizures ("split-brain" surgery that separates the right from the left hemisphere). Before surgery, when the right hemisphere saw the word "knight", it quickly made it's dictionary match because the image of the word was efficiently transferred to the word meaning dictionary in the left hemisphere.
After surgery, though, after the patient saw the word "knight" with his right hemisphere his answer was very different: "I have a picture in my mind, but I can't say it - two fighters in a ring. Ancient wearing uniforms and helmets...on horses trying to knock each other off....Knights?"
There are children and adults with a rich descriptive narrative style, but with word finding difficulties due to weaker connections in their posterior callosum. Some researchers have suggested that as a group, boys have smaller posterior callosal connections than girls, but it is more definitely true for children who had a preterm birth, dyslexic individuals, and at least some individuals diagnosed with ADHD. For those interested, callosal connections increase a great deal from the age of 6 into the teen years.
A number of implications come to mind - individuals with this right brain preference will find it easier to arrive at their words by contextual and cloze or closure-type prompts. The gifted right-hemispheric writer should be looked for and taught based on his or her strengths. Some of the early frustrations re: rapid word retrieval may get easier with time and development, and they should not become the source of academic stress and guilt.
Cerebral specialization and interhemispheric communication html or pdf
Eide Neurolearning Blog: The Right Brain Difference: The Complex Story in Our Brains
Growth in the Developing Brain