“Conversation may feel effortless, but it’s one of the most complex tasks the brain performs. It relies on multiple brain systems working together in real time,” says Dr. Seibert. These functions include:
Auditory Processing “Being able to hear clearly is a crucial first step,” says Victoria Williams, PhD, a neuropsychologist at UW Health in Madison, Wisconsin. Every conversation begins with the brain taking in sound; it must accurately decode speech while filtering out competing noise. This process is more demanding in environments with clattering dishes, music, or overlapping conversations.
Once speech enters the brain, attention networks must focus on that signal and flag it as important, says Dr. Williams.
While distractions are frequently thought of as external or environmental factors, internal “noise” can compete for attention, she says. For example, if you feel anxious in a social situation, that can take away from your ability to pay attention to the conversation, says Williams.
Working Memory Working memory allows you to hold onto the beginning of a sentence long enough to understand how it ends, says Seibert. It also helps with keeping track of earlier parts of a conversation and relevant past experiences to respond meaningfully.
The efficiency of this process depends in part on how much information can be held in the mind at one time, she says. “When working memory capacity is reduced, following longer explanations or multistep ideas can feel more taxing,” says Seibert.
Over the course of a conversation, that effort accumulates, leading to fatigue, particularly in group settings where multiple speakers increase processing demands.
“In MCI due to Alzheimer’s disease, rapid forgetting and repetition of questions or statements are common and require patience and gentle reorientation to maintain engagement in conversation,” says Seibert.
Executive Function Executive function refers to higher-level brain systems that help track topics, shift between ideas, and regulate turn-taking, says Seibert.
These systems also support interpreting tone and social cues, making reciprocal connection possible, she adds.
Williams explains that executive functioning also allows a person to integrate social information — such as humor or sarcasm — and respond at the appropriate time, rather than interrupting.
When executive systems are less efficient, listening, following conversational cues, and responding can require more deliberate effort. The brain may compensate to maintain engagement, but “compensation requires energy,” says Seibert.