 Conversation, a special type of multi-party communication, constitutes the focus of psycho-linguistic research. In the following we will look at the levels involved in this activity ranging from thought to output and vice versa. We will proceed as follows. After an illustration about the levels of conversation, we will first look at low-level processes, that is, all those processes that are non-cognitive. Then we will move on to the linguistic levels ranging from phonology to syntax. Before, finally, we will look at the higher levels, semantic interpretation and even higher levels that are applied to build models about, for example, the interlocutor. Let's first of all look at the levels in general and let's illustrate that with an example. Here we have two virtual characters, let's call them John and Bill. Let us assume that John is thirsty and that this feeling dominates his thoughts. So he is thirsty and he might think or he might want to have a beer. Linguistically or converted into a linguistic structure, this might come out as I am thirsty. Now this structure, which looks like a real sentence, stands for a syntactic string rather than an actual audible output string of phonemes, which is going to be interpreted at a later stage. So once this sentence has been uttered, once John has said I am thirsty, we have this output. Now it must be analysed by the interlocutor. So it is perceived by Bill. Now there are several mechanisms before Bill understands what John says but eventually he will understand that John is thirsty. And so this is again the linguistic stage, which is first of all analysed phonetically and then later syntactically. Eventually this string will be converted into a conceptual structure where Bill understands that John is thirsty but there might be misunderstanding so he might understand that John doesn't really want to have a beer or a pint of beer but that John eventually wants to drink some mineral water. This model incorporates several levels of speech production from the speaker's point of view and several levels of speech perception. So this is then the dividing line, speech perception and comprehension and production on the other hand. So here are the two big components of language in this particular case, speech processing. Let's now look at the levels of processing and let's start with the low level processes. Not all processes involved in language production or in language processing in general are cognitive. In speech production the articulators have to be set into motion and the production of written language, in the production of written language the motion of the hand has to be controlled. Both processes are physiological rather than linguistic. They involve subconscious movements of bodily organs controlled by the central nervous system. The comprehension of language or the perception, we have to add comprehension here because first of all we have to perceive something, later we have to understand it, comprehend it. This level also involves low level processes. For example, prior to cognition we have to analyze the sensory signal, the input signal and we have to make the results available to later linguistic levels of processing that is to the understanding system. Let's now turn to the more linguistic levels of analysis. Well one level concerns lexical processes. The goal of lexical processing is to retrieve stored knowledge, stored knowledge about the words, about the lexemes of a language in order to generate a meaningful interpretation. There are various aspects that make this task especially difficult. For example one concerns the segmentation phenomenon. Let's write down an example here in present day English. You might have the word peace talks, peace talks where in careless and not too distinct speech you might understand two things. On the one hand this could mean a plant or several types of them. On the other hand it could mean peace talks. So depending on the juncture, the phonological juncture within the word we have two possibilities of interpreting or segmenting this input string. So you see here is a problem. And another question concerns the lexical access units. How do we access the mental lexicon? This little fly indicates that it might be just a picture that retrieves information about words or lexemes or it could be a description like two legs, two wings for legs etc. Or it could be the acoustic input that retrieves lexical information. The next level is the level that is called parsing. Now parsing is an activity where on the basis of lexical and morphological information associated with each element in a sentence, a functional structure is generated. A functional structure like a structure containing information about the subject, the verb, the object etc. of the sentence. This involves two central activities. One activity concerns morphological analysis. Here we have to analyze the central building blocks. That is the morphs, words into the morphs. And it concerns syntactic analysis where the parsing process extracts the structural properties of a sentence and eventually produces a representation which contains general syntactic aspects such as subject, verb, object or information about the tense aspect and many more. Semantic interpretation is the next level. Some people call it semantic interpretation. Well, over and above the structural properties of a sentence we need to determine its meaning. This process is referred to as interpretation or semantic interpretation. It can be subdivided into two stages. Stage one is the generation of a logical form here illustrated in terms of a tree structure. That is it is an intermediate representation between the syntactic functional structure of a sentence on the one hand and the logical or conceptual representation of a sentence on the other. And this conceptual representation here illustrated by means of a network. There are some network formalisms by means of which you can represent conceptual structures. The conceptual representation is a structure which has access to the outside world and incorporates general knowledge. Thus the process of semantic interpretation has to fulfill the following tasks. It has to specify the meaning of what has been said, the meaning of the words in a sentence. It has to define the meaning relations between the words in a sentence and the phrases in a sentence. It has to couple linguistic interpretation techniques with general knowledge in order to generate a conceptual structure. But this is not the end of the story. We still have higher levels, higher levels which are well beyond the scope of the central linguistic levels. One such level is called model construction where you construct a model about the person you're talking to, a model of the interlocutor. And you construct a model of the situation in which you perform your activities. Another one is concerned with pragmatics. Now the use of language in a pragmatic interpretation you determine the communicative intention of a nut runs. Well all these insights can be converted into a working model. Now this working model will serve as the basis for the discussion of language processing in the VLC cycle linguistics class. First of all it can be subdivided into two big areas namely the area of all big components. Language production on the one hand or speech production and on the other hand we have the area of perception or comprehension. Well here you see our characters again this is our John and this is Bill, our listener. Well all these levels there can be interactive and this is one goal of cycle linguistics research. Are these levels interactive? Are they encapsulated modules? Are they applied incrementally? Well first of all let's insert some arrows which suggest they are used sequentially. This is then what happens. This is the thought and this is the output and this is the interpretation or the levels of interpretation as far as the generation of an understanding is concerned. Now the levels here are three levels. We have the level of conceptualizing, conceptualizing we have the second level here the linguistic level and finally we have our low levels in this working model which goes back to the Dutch cycle linguist Willem Leveld and as I said already it'll serve as the basis for the discussion of language processing in the VLC cycle linguistics class.