Core vocabulary

Core words work across situations

Words such as go, stop, more, different, help, you, that, and where can contribute to requests, refusals, questions, comments, descriptions, jokes, and repair. Their usefulness comes from combining them in many contexts.

ASHA’s AAC practice portal describes core vocabulary as high-frequency words that make up about 80% of words used by many people in everyday samples. ASHA notes that core vocabulary often contains pronouns, verbs, descriptors, and question words. The figure comes from language samples and should not become an 80% design quota for every person.

Core and fringe belong together

Core vocabulary supports flexible sentence building. Fringe vocabulary supplies lower-frequency or context-specific words, often including names, foods, places, hobbies, diagnoses, slang, and technical terms.

“Want,” “different,” and “look” cannot replace the name of a best friend, a painful body part, a favorite train model, or a medication. ASHA states that combining core and fringe vocabulary can increase AAC use. A useful system gives the person both reusable language and personally meaningful specificity.

Frequency is only one selection factor

A word can be infrequent and essential. Emergency messages, consent language, identity terms, private body words, and a trusted person’s name may need immediate access even if they rarely appear in a general corpus.

Selection should consider the person’s language, dialect, culture, age, literacy, relationships, settings, humor, interests, health, safety, and changing life. Translate concepts with a qualified language partner rather than copying an English layout word for word.

Model without requiring imitation

Communication partners can model words on the person’s system while speaking naturally, often called aided language input. Modeling shows possibilities and where language lives. It should not turn every interaction into a quiz.

Allow the person to watch, respond in another mode, change the topic, or say nothing. Avoid hand-over-hand selection that authors a message for the person. A partner can support access, position a device, or clarify a choice while preserving authorship.

Stable access supports motor learning

Frequently moving words can make a system harder to navigate. Qualified AAC teams consider stable locations, visual access, motor access, organization, and language growth together. Hiding words because the person has not demonstrated them can create a circular barrier.

Keep the device charged, mounted, and available across home, school, community, healthcare, and leisure. ASHA states that AAC users should always have access to their tools or devices. Prepare a tested backup for charging failures, water, outdoor use, repair, or transport.

A fictional cooking-club example

Amara joins an AAC-supported cooking club. Her system already includes core words such as open, more, stop, hot, help, different, and where. The team adds fringe words for tortilla, cilantro, the club members’ names, and Amara’s preferred hot sauce.

Across 20 sampled messages, Amara uses core vocabulary in 14 and fringe vocabulary in nine; three messages contain both. The overlapping counts are expected, so they should never be added into one percentage.

Amara makes requests, comments, rejects an ingredient, asks a question, and tells a joke. The team records five communicative functions represented, plus two missing words Amara requested. This small sample describes system use rather than language capacity or treatment effect.

Measure access and communication opportunity

Track whether the system and backup were available, whether partners recognized the message, which functions the person expressed, and which vocabulary gaps appeared. Keep spontaneous, prompted, copied, and partner-authored selections separate.

A low word count may reflect few opportunities, inaccessible positioning, slow navigation, unfamiliar partners, fatigue, or a missing vocabulary item. Use raw counts and opportunity definitions alongside percentages.

Review vocabulary with the communicator

Ask which words feel useful, outdated, embarrassing, missing, too public, or hard to find. Add language for new people, health needs, school, work, relationships, sexuality, hobbies, travel, and emergencies as life changes.

Vocabulary never defines communication potential

A person can communicate through gesture, sign, speech, writing, movement, facial expression, objects, pictures, and a device within the same interaction. Core-word use should expand options rather than replace effective modes.

Avoid withholding interesting fringe words until someone “masters” core. Also avoid measuring vocabulary size as a proxy for intelligence. System access, partner responsiveness, opportunities, language experience, fatigue, and motor demands all affect observed use.

The BACB Ethics Code addresses competence, understandable communication, involvement, consent, assent when applicable, assessment, and intervention for covered professionals. Behavior analysts should collaborate with AAC-qualified professionals and stay within scope.