Ming from Agents of Speech breaks down why younger kids often respond faster to speech therapy: their habits aren't set yet. Older kids understand instructions better and can stay motivated, but they've had years to practice bad patterns, making change harder.
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If we're dealing with younger child it's easier to teach something because the habits hasn't been formed yet. Say they're so used to rejecting, pushing you away, pulling your hand, not using words that habit is so strong they only care about the things they want to care about and not the things we want to push on them. For instance, younger children are easier to teach when they're younger because the habits aren't as well established as before Right? Right. Older children are easier to teach there's always pros and cons Children are easier to teach because they're able to understand the task a lot better because they're more mature, have better cognitive skills their language skills although lower than typical developing children they understand better in terms of receptive language when you tell them what you want them to do it's easier for them to comprehend it's just that the trade off between their habits and the reward that they're getting out of and whether they understand this is going to help with their lives or not It's a battle.