The lines should be interrupted. I open a random page in a best selling sci fi novel to find a dialogue, the author has whole paragraphs between utterances. Open Harry Potter to find a dialogue with Harry, Ron and Hermione, every utterance is accompanied by a description, and sometimes a few lines of describing physical actions.
Blocks of nothing but dialogue are generally not fully imagined scenes, people do not generally stand and talk to each other without moving, they move, have expressions, they think.
In real life, unless people are shouting over each other, every single time somebody says something, a listener has to process and understand whatever was said, this changes their mental state, they have a reaction of some sort from mild to severe, they formulate a response. The opposite happens in the other direction. If you provide NOTHING in-between lines of dialogue and leave all of that to the imagination of the reader, the reader will perceive these line as occurring too fast, and therefore being unrealistic. It is rushed, no matter what you do. This is WHY authors add "stage business" in-between speaking parts, so the reader has time to process whatever was said.
For unspoken communications, describe what people think and understand. Even from a single POV. Here is an "awkward silence":
For a moment she thought she must have heard him wrong, when Milly realized what Nick had said, she did not answer. She had no answer. She averted her eyes to the floor for a moment and felt embarrassed for him. When she thought of a response and looked up to give it, she realized Nick seemed embarrassed for himself. She held her tongue. Should she let him speak, or just walk away?
It may not fit your story, that isn't the point: An "awkward silence" is awkward for some reason, it means it isn't easy to formulate a response and both parties know it. It usually involves something embarrassing or shocking that focuses the attention of the listener on something else, or makes them want to answer with anger or scolding or insult that isn't appropriate for the setting. What makes it awkward, or difficult to navigate? What are the feelings involved?
As for "comprehension":
Karen grew excited. "No, dummy, it's the opposite!" Nick's brow knitted in confusion. She said, "He cut his own brake line! Get it?"
Before her eyes, Nick's knitted brow relaxed, his confusion evaporated and transformed into astonishment. "Oh my GOD!" he whispered. "Of course! Why didn't I think of that?"
And so on. What are they thinking? Why? What are they remembering that prompts their realizations?
Patricia reached out for Devin.
Why? Did she feel pity and an urge to comfort him? Was it love and a need for physical closeness? Lust and an urge to feel his body against hers? Grief that he felt so distant and a plea for him to return to her?
Some internal state in Patricia causes her at that moment to reach out and try to connect, and you are leaving it to the reader's imagination precisely what kind of connection is sought. It does not have to be said in dialogue, our speech seldom contains much of our internal feelings and urges.
If it is not perfectly clear in the context of the story, then it should be described. If it is perfectly clear in the context, there is nothing wrong with it, the reader understands the physical reaction and sees nothing wrong with it. Either it was described earlier in the context, or it needs to be described now: What emotion is strong enough to provoke this physical action and make it an emotionally plausible action?