as always our introduction stimulus and stimulus class what is a stimulus stimulus is the S and our SRS contingency the SRS contingency also known as ABC antecedent Behavior consequence SRS is stimulus response stimulus and that is the basis for operant behavior which is what we work on and study and change in Aba stimulus is any change in the environment that evokes a functional relation stimulus classes can include physical formal features so characteristics of stimuli and be functional they can affect behavior and plural and parole could be our antecedents and consequences in relation to where they appear in terms of our behaviors and then arbitrary stimulus classes they might not share any features or formal characteristics but they'll affect Behavior the same way that's our brief rundown let's get right into stimulus Cooper says as an energy change that affects an organism in other words a change in the environment all these things around us all these different changes noises smells lights people that enter the room people that leave the room people talking all these different things are just stimuli affecting our behavior in one way or another the environment happens behavior is US reacting to that environment and then the environment reacting back on us these are all stimulus changes so the entire class is talking loudly teacher walks in the class here is stimulus you have a date planned tonight until you receive a text canceling the date the text is a stimulus energy changes that affect an organism humans in our case changes in the environment just think about stimulus control you want to bring Behavior under stimulus control or does that mean that means in the presence of certain stimuli we're going to see certain behavior in the presence of certain stimuli we won't see certain Behavior this is what we want to see right libraries what kind of behavior the library evoke but quietly respectful of other people's spaces we might wear headphones we're just generally very polite and buttoned up right that library and all the things inside the Library the smells and the books and the sounds have stimulus control over certain behaviors so as you can see stimulus and stimuli are incredibly important in an ABA think about where else we use them classes SDS and S deltas I mean less discrimination equivalence spading digitalization stimulus prompts the list goes on and on and on right stimuli control Behavior stimulus is just an energy change it affects an organism that evokes behavior that punishes that reinforces have to have to understand how important stimuli and stimulus are in Aba with that said let's talk about stimulus classes there's different classes of stimuli do different things and have different characteristics before we're going to kind of look at are formal and plural functional and arbitrary we're going to look at functional and temporal and kind of the same light but form one arbitrary we're going to look at separately along with functional how do we create these new stimulus classes well through anything else right parent and as you study I always try to point out the patterns and the things that kind of run together and go together and the similarities and the concepts that we use okay the more you can relate all our Concepts together the better you're going to get as a practitioner and at the exam if you want to create a new stimulus class well we just need to do some stimulus stimulus pairing right and typically this is going to be for functional stimulus classes right so the formal stimulus class they still need to share characteristics but if we want to have a stimulus evoke a behavior what you currently doesn't we need to do some pairing right so we're going to present two stimuli at the same time repeatedly multiple trials which will hopefully result in one stimulus acquiring the function of the other stimulus so first let's look at physical formal or feature stimulus classes obviously they share common physical forms they're described by physical features sizes big small colors red blue orange green white weights heavy light and special relation where they occur in our environment include infinite number of stimuli so let's look at some examples feature stimulus crashes create Concepts and why is that so well if we take a bunch of stimuli like tails and noses and paws and four legs put them all together we might get a stimulus class for a a feature class of dogs right because dogs all share these same stimuli cats also share tails and noses and paws and four legs right so we're creating different concepts using these feature stimulus classes and then we teach Learners to discriminate between the different classes you get an idea of how concepts are formed if we take wings and cockpits and landing gear and propellers right combine them all make airplanes all these airplanes formula stimulus class and then cheese bread toppings crust put them all together right all these feature stimulus classes share these common physical features and forms now if we look at functional stimulus class which is what we're typically more concerned with right we're all about function here they all affect the behavior the same way so does the stimulus temporarily affect the behavior stimulus permanently affect the behavior but the questions you're going to be asking yourself as you identify the different stimuli and the functions of those stimuli and when we think functional we want to think temporal because what in ABA do we say evokes Behavior antecedents what reinforces and punishes behavior consequences so if we look at our SRS contingency are antecedents and our consequences are going to make up these functional stimulus classes right because if you think of ABC or antecedent stimuli is going to evoke that behavior our consequence stimuli is either going to reinforce or punish that behavior so functional stimulus classes also create functional stimulus classes functional stimulus classes affect Behavior the same way we're looking at different stimuli and how they're affecting behavior let's ask ourselves does the stimulus temporarily affect the behavior or does the stimulus permanently affect the behavior in the future in other words think temporally think about the stimulus in relation to the behavior that's occurring what do we mean by that when we have SRS stimulus response stimulus or ABC we have antecedents and we have consequences and ideally we want those antecedents to happen as close to the response as possible same with the consequences when you're thinking antecedents you're thinking consequences you're thinking what is evoking that behavior what is reinforcing or punishing that behavior all those things are just stimuli and all those different types of antecedent stimuli make up a functional stimulus class all those different consequences stimuli can make up a functional stimulus class whatever is affecting the behavior the same way can make up functional stimulus classes so for example different types of music Make You Dance Rock rap pop whatever type of music you're listening to can all evoke the behavior of dancing stop signs red lights and hand signals make you stop different chairs make you sit down different tokens might enforce you all these different stimuli make up a class that affect Behavior the same way and then arbitrary stimulus classes they evoke the same response do not share features not physically similar they're not formally similar okay they're very arbitrary in relation to one another but when we look at our behavior and responses they're all evoking the same exact response for example we say 50 we say one divided by 2. say divided evenly and when we say 0.5 what we're really saying is f and we say apple banana avocado and grapes what we're saying are fruits apples bananas avocados and grapes don't necessarily share physical or formal similarity but they all make up a a class and they evoke the same responsive fruit and then monkeys giraffe tigers and lions all make up animals so you can see all of our stimulus classes start to form these Concepts right start to form these heuristics where we combine different stimuli together making classes and making Concepts arbitrary stimulus class is similar to functional stimulus classes right they evoke the same response however they just don't share the same features wrapping it up stimulus the S and our SRS contingency changes in the environment that evoke a functional relation okay so anything that affects the organism any change noises sounds people things objects everything in our environment that's constantly changing right can lead to we can take those stimuli and we can create classes we can create stimulus classes by physical form or features we can group stimuli together by their function and how they temporarily appear in relation to our responses or we can create arbitrary stimulus classes stimulus stimuli that affects evoke the same behavior don't share any formal characteristics thank you for watching I hope you enjoyed for our bcba materials be sure to check out bcbastudy.com for three practices exams our fifth edition task list study guide and our comp