Listen to the sounds in the room. And notice how each one articulates the space of consciousness.
Sam Harris often uses this expression, or similar ones: sense impressions "articulate" the space of consciousness (awareness). They "modify" it. They "pertubate" it.
In other meditations, this statement includes not only hearing but also all other sense impressions defined by Buddhist psychology:
All of these, as they arise, "articulate" or give form to consciousness.
Please note that in Buddhist psychology, the mind itself is also considered to be a sense system. Thus, thoughts have the same status as sights, sounds, etc. The only difference is that the mind also acts as an integrator (this is well explained by Culadasa, in his analogy of the mind being a share working workspace for all senses). Thus, thoughts too "articulate the space of consciousness", just as sound etc does.
Daniel P Brown (extended quote)
Daniel P Brown uses a different term for what Sam Harris calls "articulation": he uses the expression "the mind takes the shape" of the sense impressions, and he uses an analogy to the mirror metaphor. In analogy, a mirror surface "takes the shape" of the reflected objects in the moment of reflection.
The following quote is taken from the chapter on concentration meditation. It shows how complex the underlying Buddhist tradition is. it is meant as teaser to dive more deeply.
The intended object can come from any of the six senses—a sight, sound, smell, taste, touch sensation, or thought. Since a common approach to concentration training is to use a visual object, the term could also be translated as “visualization.” For each of the six sense systems described in Buddhist psychology the mind is said to take the shape of or reflect the qualities of its intended object as if it were a reflected image in a mirror (snang brnyan; Skt., pratibimbakam (D. P. Brown & Thurman, 2006, p 224)
"The mind arising in that form"
Tashi Namgyal (2011) uses slightly different terminology:
Based upon any one of the five sense consciousnesses, the sixth consciousness can, does, and will generate generalized abstractions that we normally take to be the external object that is perceived by that particular sense consciousness. Whether it is a generalization of form or a generalization of sound, it is the sixth consciousness’ generalized abstraction of the sense experience, and it is, therefore, in and of itself, not an external object. These generalized abstractions that are experienced by the sixth consciousness are not true external objects; they are projections of the sixth consciousness, and therefore, in a very true sense, they are the mind arising in that shape. They are the mind arising as that apparent form or as that apparent sound, and forth. (Namgyal 2011).
Brown, D. P., & Thurman, R. (2006). Pointing Out the Great Way: The Stages of Meditation in the Mahamudra Tradition (Annotated). Wisdom Publications.
Namgyal, L. T., & Rinpoche, K. T. (2011). The Ninth Karmapa’s Ocean of Definitive Meaning (New ed). Snow Lion. https://www.amazon.com/Ninth-Karmapas-Ocean-Definitive-Meaning/dp/155939370X
Yates (Culadasa), J., & Immergut, M. (2017). The Mind Illuminated: A Complete Meditation Guide Integrating Buddhist Wisdom and Brain Science for Greater Mindfulness. Hay House Uk.