Last updated 2026-07-09
Communication symbols are pictures, line drawings, or photographs that stand in for words. For an autistic child with little or no spoken language, they can be the difference between being understood and total frustration. The child points to, hands over, or touches a symbol on a board, book, or device, and whoever's with them responds as if the word had been spoken. PCS, PECS, and ARASAAC are the names you'll hear most often, and research shows symbol-based systems don't delay speech and often help it along. Most families start with somewhere between 3 and 10 core symbols.
What these symbols actually are
Symbols take different forms. Some are realistic photos of objects and people the child already knows; others are stylized drawings meant to be recognized instantly no matter what language or culture a child comes from. Some systems use color coding, verbs in one color, nouns in another, so kids start picking up grammar patterns just from using the board.
All of this sits under the wider umbrella of augmentative and alternative communication, or AAC, which the American Speech-Language-Hearing Association defines as "all forms of communication (other than oral speech) that are used to express thoughts, needs, wants, and ideas" [1]. Symbols are one of the easiest ways into AAC because they don't require reading or much fine motor skill.
Symbol use isn't something to reach for only after other things fail. Speech-language pathologists generally recommend starting early, before a lack of communication turns into behavioral frustration, and the evidence is solid enough that the American Academy of Pediatrics names AAC as a recommended communication support in its autism guidance [2].
PCS, ARASAAC, and PECS: how they differ
Three symbol sets come up constantly, and they're genuinely different in design, cost, and evidence base.
Picture Communication Symbols (PCS) are the line drawings that ship with Boardmaker software from Tobii Dynavox, and they're probably the most widely used symbol library in North American schools and therapy rooms. The current Boardmaker catalog holds over 45,000 symbols [3]. Color coding stays consistent throughout: green for verbs, yellow for descriptors, orange for nouns. The catch is price. Boardmaker licenses start around $349 a year for home use as of 2024, though many school districts cover access.
ARASAAC (Aragonese Portal of AAC) symbols are free. The Spanish government funds the library and releases everything under a Creative Commons license: over 12,000 color symbols plus thousands more in black and white [4]. The quality holds up well, and plenty of free apps and low-tech boards run on ARASAAC graphics. If cost is the obstacle, start here.
PECS (Picture Exchange Communication System) isn't really a symbol set at all, it's a structured teaching protocol, developed by Andy Bondy and Lori Frost in the late 1980s at the Delaware Autistic Program. It uses photographs or simple drawings, but the method matters as much as the images: children learn to physically hand a symbol to another person in exchange for something they want. A 2002 randomized study in the Journal of Applied Behavior Analysis found children using PECS made gains in spontaneous communication, and some showed increased spoken words alongside symbol use [5].
Here's how they stack up:
| Symbol System | Cost | Symbol Count | Evidence Base | Best For |
|---|---|---|---|---|
| PCS (Boardmaker) | ~$349/yr | 45,000+ | Extensive, widely cited | School/therapy settings |
| ARASAAC | Free | 12,000+ color | Growing, peer-reviewed | Families on a budget |
| PECS protocol | Training required (~$200+ workshop) | Variable | RCT-supported | Early communicators, exchange-based learning |
| SymbolStix | Subscription | 50,000+ | Used in research | Apps, digital boards |
Photograph-based systems exist too, mainly for children who struggle to connect a drawing with the real object it represents. That gap trips up more kids than most parents expect.
Does symbol use actually help kids communicate better?
Yes, and the evidence behind it is stronger than for a lot of interventions families spend real time and money chasing. A 2014 systematic review in the American Journal of Speech-Language Pathology looked at 23 studies on AAC and autism and found consistent evidence that symbol-based systems increased communicative acts in children on the spectrum, with no sign that AAC suppressed speech development [6]. That matters, because the fear that symbols will "replace" speech and kill a child's motivation to talk is one of the biggest reasons families hold back.
The full picture has some nuance. AAC doesn't automatically produce spoken words. What the research actually shows is that it doesn't hurt speech, and often it gives a child enough of a communication outlet that frustration drops and spoken attempts become more frequent rather than less. The National Institute on Deafness and Other Communication Disorders notes that for nonspeaking or minimally verbal individuals, AAC "may help them communicate more effectively" [7].
For children who are minimally verbal, meaning fewer than 20 functional words, symbols often become the main route to communication of any kind. The real question isn't symbols versus speech, it's using symbols while also working on speech alongside a speech therapist.
Nobody has clean data on the single best age to start. Clinical consensus from ASHA and most SLPs leans toward starting as early as possible, often around 18 to 24 months once delays become visible, and the early intervention window before age 3 genuinely matters here.
Core words versus fringe words
This is one of the most useful things a parent can learn, and most AAC training explains it poorly.
Core vocabulary is the small set of words that makes up most of what anyone says, regardless of topic: "more," "go," "stop," "want," "help," "no," "yes," "I," "you," "that." Research consistently shows roughly 200 to 400 words account for 80% of what typically developing speakers say [8]. These words are flexible. "Go" works at the park, in the car, during play, at bedtime.
Fringe vocabulary is topic-specific: "dinosaur," "swing," "cheese," "iPad." These matter to one particular child but don't carry over to other situations.
Early AAC boards used to be built almost entirely from fringe words, since it felt more useful to hand a child symbols for favorite foods and toys. The problem is that a board full of fringe words lets a child request specific things but leaves them with no way to say "stop" when something hurts or "more" when they want a favorite activity to continue.
Most SLPs now build around core vocabulary first, adding a small amount of personalized fringe on top. A starting board of 12 to 20 symbols, mostly core words with a few high-motivation extras (a favorite food, the family pet's name), is a reasonable place to begin, though exactly which symbols to start with is a decision best made with a speech-language pathologist who knows your child.
Low-tech symbol boards: what they are and when to use them
A low-tech symbol board is exactly what it sounds like: paper or laminated cards with printed symbols, arranged on cardboard, in a binder, or as a small flip book. No battery, no screen, no app.
They have real advantages. A laminated card survives the bathtub, the car seat, and being thrown across a room; they're cheap or even free if you print ARASAAC symbols at home; and they're always on, with no loading time and no dead battery at the worst possible moment.
For very young children, or kids just starting with symbols, a simple first/then board, a two-panel strip showing what's happening now and what comes next, is often the first low-tech tool an SLP introduces. It's not a full communication system, but it gives a child a visual anchor for daily transitions, which cuts down on the kind of communication breakdowns that come from anxiety.
Activity boards are another low-tech staple: a snack-time board with drink and food choices, a bath-time board, a playground board, each one built for a specific moment so the child has an actual reason to use the symbols in front of them.
Low-tech doesn't mean limited. Plenty of children communicate complex ideas through well-designed paper systems. The PODD (Pragmatic Organisation Dynamic Display) communication book, developed by Gayle Porter in Australia, is a sophisticated low-tech system used with children who have complex communication needs, including many autistic children [9]. It's organized by communicative function rather than category, a genuinely different approach that some children find far more intuitive.
How do high-tech AAC devices use symbols, and are they worth the cost?
High-tech AAC devices are tablets or dedicated devices running software that displays symbol grids. The child selects symbols to build a message, and the device speaks it aloud using text-to-speech. PRC-Saltillo, Tobii Dynavox, and Lingraphica make most of the dedicated devices on the market.
They're expensive. A purpose-built AAC device usually runs between $6,000 and $10,000 before insurance [10]. Medicaid covers AAC devices in most states for children who qualify, and private insurance has gotten somewhat better since the 21st Century Communications and Video Accessibility Act and various state parity laws. Getting there still means a formal AAC evaluation from a speech-language pathologist, a recommendation letter, and often a long wait for prior authorization.
Apps on regular iPads cost a fraction of that. Proloquo2Go from AssistiveWare runs around $250 as a one-time purchase and uses a PCS symbol library. TouchChat, LAMP Words for Life, and Snap Core First are other established options, each built around its own approach to symbol layout.
Whether the high-tech route is worth it depends on the child. Dedicated devices produce speech output, which matters when talking with people who don't know the child's symbol system, and they can hold hundreds or thousands of symbols across pages that grow as the child does. For a child who's showing clear potential for complex communication, that expense tends to pay off. For a child just starting to explore symbols, a low-tech board while you wait on insurance approval isn't a step backward at all.
Worth saying plainly: device abandonment in AAC is common. Studies estimate that 25 to 33% of AAC devices end up unused [11]. The device itself doesn't solve anything; consistent, supported use does. That takes training for the family, more than for the child.
What is aided language stimulation, and why do speech therapists use it?
Aided language stimulation, also called modeling or AAC modeling, means the adult points to or activates symbols while talking normally to the child. If you're saying "let's go eat lunch," you also touch the "go" and "eat" symbols on the board or device as the words come out of your mouth.
The logic comes from how spoken language develops: children hear thousands of hours of speech before they ever produce a word themselves. Symbol users need that same volume of input. Handing a child a board and expecting them to use it without ever watching an adult use it first is a bit like expecting a child to read without ever seeing anyone else do it.
The research backs this up. A 2014 study in Augmentative and Alternative Communication found that aided language stimulation was linked to increases in symbol use by children with autism when communication partners did it consistently [12].
In practice, this means everyone around the child needs to model, not just the SLP for an hour a week. Parents, siblings, teachers, and grandparents touching the symbols during ordinary conversation is what actually moves outcomes. It feels strange at first and then becomes second nature.
A common mistake is only pointing to symbols when prompting the child to say something. That teaches the child that symbols are for being tested, not for talking. Modeling should happen all day long, with no expectation that the child mirrors it back right away.
Which symbol system works best for nonverbal or minimally verbal autistic children?
There's no single system that's universally best for minimally verbal autistic children. That's not a dodge, it reflects real differences in how children process visual information, what motivates them, and what their motor skills allow.
Still, some patterns show up in the research. Very young children, or those with significant cognitive delays, often do better starting with a small set of high-contrast, highly motivating symbols rather than a large grid. Starting big overwhelms. Three symbols that matter enormously to the child, like "more," "help," and a favorite food, tend to produce faster early wins than a 64-symbol board.
For children with apraxia of speech alongside autism, the case for a full AAC system is especially strong. Apraxia makes spoken word production unreliable even when the child knows the word, so a symbol system gives a dependable way to communicate while speech therapy works on the motor planning underneath.
For children who don't respond to two-dimensional drawings, object-based systems are an option. Actual physical objects, a spoon for mealtime, a small car for a car trip, can serve as early symbols, with the goal of moving toward more portable, flexible systems over time.
The best approach starts with an SLP completing a formal AAC assessment, weighing the child's visual skills, motor skills, cognitive level, motivations, and the communication environment at home and school. No app or article replaces that evaluation.
How do you introduce communication symbols at home?
Start with something the child genuinely wants. That sounds obvious, but it decides everything about motivation. If your child would move mountains for crackers, make a cracker symbol the first one. The exchange has to matter to them.
For a first board, three to five symbols is plenty. Put them somewhere highly visible in the right context: on the refrigerator for food requests, on the edge of the bathtub for bath choices. Don't move the board around constantly at first; predictability helps.
Model constantly, without pressure. Touch the symbol as you say the word, through normal daily talk. If your child grabs your hand to drag you to the kitchen, touch the "eat" or "want" symbol and say "eat? You want to eat?" Then follow through right away. The symbol has to reliably get results, or the child stops bothering with it.
Expect a long stretch before the child starts using symbols on their own. Some take weeks, others take months. Resist the urge to prompt constantly or turn it into a test. Prompting too much can create prompt dependence, where the child only uses the symbol when asked, which isn't really functional communication.
Keep a few symbols portable. A small keyring with four or five laminated cards can go to the grocery store, the car, the playground. Limiting symbols to one room at home accidentally teaches the child that symbols only work in that room.
A tool like Little Words can support daily practice by giving parents a structured, symbol-rich setup that adapts to what the child already knows, useful for the stretches between therapy appointments. Pairing that with a speech therapist who has AAC experience helps too, since home practice works best when it mirrors what's happening in sessions.
Do communication symbols work for autistic adults too?
Yes, and this has grown as more autistic adults have spoken publicly about their own communication needs.
Some autistic adults who grew up without AAC find symbol-based or text-based systems later in life. Others go through periods of reduced verbal fluency, sometimes called autistic burnout or situational mutism, where they need symbol or text support even though they usually speak. This is more common than most medical literature admitted even a decade ago.
For older teens and adults, the symbol sets and display styles often look different, since vocabulary needs shift. Social communication, medical settings, work, and getting around the community become more relevant categories. The core vocabulary approach still holds underneath it.
AAC for adults falls under the same speech therapy framework, though insurance pathways and access vary. Speech therapy for adults with autism is a legitimate and underused resource, and an adult AAC assessment from an SLP is the right place to start.
Autistic self-advocates have pushed back, usefully, against the assumption that AAC is only for children or only for people who "can't talk at all." Communication needs shift with time, context, and stress. A system that helps someone communicate more reliably on hard days is worth having, at any age.
How symbols fit into the bigger picture of autism speech therapy
Symbols are one tool inside a much larger approach to autism spectrum speech therapy. Most SLPs working with autistic children address several things at once: social communication, speech production, language comprehension, and AAC as needed.
Symbol systems handle the output side, giving the child a way to send a message. But communication also means understanding what's coming in, taking turns, holding a topic, and reading social cues, and symbol training alone doesn't cover any of that.
Some children using symbols also show echolalia, repeating phrases they've heard before. Echolalia and symbol use can coexist, and a good SLP will help sort out whether a child's echolalic phrases are actually serving a communicative function, which they often are. Understanding what echolalia means is part of reading the child's whole communication picture.
For children with motor-based speech difficulties alongside autism, childhood apraxia of speech and symbol-based AAC often go together. The AAC doesn't replace speech therapy for apraxia; it gives the child a way to communicate while that therapy does its slow work.
If you're not already working with an SLP, online speech therapy is a real, often insurance-covered option that has widened access considerably, especially for families in rural areas or without local specialty providers.
Frequently asked questions
At what age should an autistic child start using communication symbols?
There's no minimum age, and earlier is almost always better. ASHA's clinical consensus supports introducing AAC as soon as a communication delay shows up, sometimes as early as 18 months. Waiting to see if speech develops on its own before bringing in symbols isn't recommended by major professional bodies, and symbols don't get in the way of speech development.
Will using picture symbols stop my child from learning to talk?
No. A 2014 systematic review in the American Journal of Speech-Language Pathology found no evidence that AAC suppresses speech, and several studies actually found increases in spoken communication alongside symbol use. This worry has been studied repeatedly and hasn't held up. Most SLPs treat AAC as something that works alongside speech therapy, not a replacement for it.
What is the PECS method and how is it different from other symbol systems?
PECS, the Picture Exchange Communication System, is a teaching protocol where the child physically hands a picture symbol to another person to make a request. That exchange is the whole point. It runs through six phases, starting with single-picture requests and building up to full sentences, and what sets it apart from other systems is that the child initiates the exchange rather than waiting for a prompt.
Are there free autism communication symbol resources online?
Yes. ARASAAC (arasaac.org) offers over 12,000 free color symbols under a Creative Commons license, and you can download, print, and laminate them at home. Widgit and Mulberry Symbol sets have free components too, and plenty of SLPs build activity boards from these free resources. Boardmaker with PCS symbols does cost money, though your child's school may already have a license.
How many symbols should a beginner board have?
Most SLPs recommend starting with 3 to 10 symbols for a brand-new user. The exact number depends on the child, but starting small lets you model consistently and gives clear choices without overwhelming them. Focus on core words like "more," "help," "stop," and "want," plus one or two high-motivation words specific to your child.
What is aided language stimulation and how do I do it at home?
It means touching or pointing to symbols on your child's board as you talk naturally throughout the day, not prompting the child to use them but showing how they're used. Touch "go" when you say "let's go." Touch "eat" at mealtimes. Research points to this as the main driver of symbol learning, so the goal is modeling consistently, all day, across whatever you're already doing.
Can an autistic child use both symbols and speech at the same time?
Yes, and for many children that's actually the goal. Using symbols alongside spoken words, known as multimodal communication, is how most successful AAC users get by. Children who start with symbols and also get speech therapy often develop spoken words over time, with the symbol system staying available as a backup for moments when speech is harder.
What's the difference between a communication board and a PECS book?
A communication board is a fixed display of symbols on a surface: a binder page, a laminated card, a board. A PECS book is a portable binder where individual symbol cards are stored with Velcro so the child can pull one off and hand it over, following the specific PECS teaching protocol. Communication boards are more of a general-purpose tool that families and therapists use without being tied to one method.
Does insurance cover AAC devices and speech therapy for autistic children?
Medicaid covers AAC devices in every state for eligible children, usually requiring an SLP evaluation and prior authorization. Private insurance varies by state and plan but has gotten better over time, and the 21st Century Communications and Video Accessibility Act put some federal frameworks in place. Many states also have autism insurance mandates covering speech therapy and AAC. Your SLP can walk you through the paperwork for device approval.
What do I do if my child refuses to use their communication board?
Refusal usually comes down to one of a few things: the symbols don't represent anything the child actually cares about, the prompting feels like a test instead of a conversation, or the board is too big and visually busy. Try revisiting which symbols are on there, shrinking the board, backing off the pressure while increasing your own modeling, and making sure using a symbol reliably gets the child what they want. An SLP can watch and help troubleshoot.
How is symbol-based communication different from sign language for autism?
Symbol systems are visual images on a surface or screen; sign language uses hand and body movements. Both count as AAC. Signs need consistent fine motor control and a partner who knows them, while symbols work with anyone who can see the board. Plenty of children use both, and there's no evidence one beats the other: it comes down to the child's motor skills, the communication environment, and what the support team recommends.
Can autistic adults use communication symbols, or is this just for kids?
Adults use them too, and the autistic adult community has been vocal about needing AAC options at any age. Some use symbols situationally, in high-stress moments or when verbal communication breaks down, while others rely on them as a primary system. The vocabulary and layout look different for adults, but the underlying approach is the same, and an adult AAC evaluation from an SLP is the right place to start.
What symbol app works best on an iPad for autistic children?
Proloquo2Go is the most researched app in peer-reviewed literature and uses PCS symbols. TouchChat and LAMP Words for Life are also widely used clinically, and LAMP's motor-learning approach clicks strongly for some children. Which one is "best" depends on the child's needs, the SLP's experience, and your budget. Most offer free trials, so it's worth involving an SLP before you commit to a paid system.
Sources
- ASHA, Augmentative and Alternative Communication Overview: ASHA defines AAC as 'all forms of communication (other than oral speech) that are used to express thoughts, needs, wants, and ideas'
- American Academy of Pediatrics, Management of Children with Autism Spectrum Disorder: AAP guidance on autism management includes AAC as a recommended communication support for children with ASD
- ARASAAC, Aragonese Portal of AAC: ARASAAC offers over 12,000 color symbols released free under a Creative Commons license, funded by the Spanish government
- Charlop-Christy et al., Journal of Applied Behavior Analysis, 2002: A 2002 study in JABA found that children using PECS showed gains in spontaneous communication and some showed increased spoken words alongside symbol use
- Ganz et al., American Journal of Speech-Language Pathology, 2014: A 2014 systematic review of 23 studies found consistent evidence that symbol-based AAC increased communicative acts in children with ASD, with no evidence that AAC suppressed speech development
- National Institute on Deafness and Other Communication Disorders, AAC: NIDCD notes that AAC 'may help them communicate more effectively' for nonspeaking or minimally verbal individuals
- Gayle Porter, PODD Communication Books, Cerebral Palsy Alliance Research Foundation: PODD (Pragmatic Organisation Dynamic Display) is a sophisticated low-tech communication system organized by communicative function, used with children who have complex communication needs including autism
- ASHA, AAC Funding Resources: Purpose-built AAC devices typically cost between $6,000 and $10,000 before insurance coverage
- Johnson et al., AAC device abandonment review, Disability and Rehabilitation: Assistive Technology: Studies have estimated that 25 to 33% of AAC devices end up unused, with device abandonment a recognized challenge in the field
- Cafiero, Augmentative and Alternative Communication, 2014 (aided language stimulation): Aided language stimulation was associated with increases in symbol use by children with autism when implemented consistently by communication partners