the same objects as in the past: angles, illumination, and surrounding contexts are different. Therefore, our mental representations have to be modified; adaptation-learning is required (Grossberg, 1988; Kosslyn, Ganis, & Thompson, 2001).

All learning and adaptive algorithms maximize correspondence between the algorithm internal structure (knowledge in a wide sense) and objects of recognition; the psychological interpretation of this mechanism is KI. The mind-brain mechanisms of KI are discussed in (Levine & Perlovsky, 2008). As discussed below, it is a foundation of higher cognitive abilities, and it defines the evolution of consciousness and cultures.

## 2.4 Grammar, Language Emotionality, And Meanings

Language and voice started separating from ancient emotional centers possibly millions of years ago. Nevertheless, emotions are present in language. Most of these emotions originate in cortex and are controllable aesthetic emotions. Their role in satisfying KI is considered in the next section. Emotional centers in cortex are neurally connected to old emotional limbic centers, so both influences are present. Emotionality of languages is carried in language sounds, what linguists call prosody or melody of speech. This ability of human voice to affect us emotionally is most pronounced in songs. Songs and music, however, is a separate topic (Perlovsky, 2006d; 2008; 2010a) not addressed in this paper.

Emotionality of everyday speech is low, unless affectivity is specifically intended. We may not notice emotionality of everyday "non-affective" speech. Nevertheless, "the right level" of emotionality is crucial for developing cognitive parts of models. If language parts of models were highly emotional, any discourse would immediately resort to fights and there would be no room for language development (as among primates). If language parts of models were nonemotional at all, there would be no motivational force to engage into conversations, to develop high cognitive models driven by language. Higher cognition would not be developed. Lower cognitive models, say for object perception would be developed because they are imperative for survival and because they can be developed independently from language, based on direct sensory perceptions, like in animals. But models of situations and higher cognition are developed based on language models (Perlovsky, 2004; 2006a,c; 2007b; 2009a; 2010f,g,m). As discussed later, this requires emotional connections between cognitive and language models. 

Primordial fused language-cognition-emotional models, as discussed, have differentiated long ago. The involuntary connections between voice-emotion-cognition have dissolved with emergence of language. They have been replaced with habitual connections. Sounds of all languages have changed and, it seems, sound-emotion-meaning connections in languages should have severed. If the sounds of a language change slowly the connections between sounds and meanings persists and consequently the emotion-meaning connections persist. This persistence is a foundation of meanings because meanings imply motivations. If the sounds of a language change too fast, the cognitive models are severed from motivations, and meanings disappear. If the sounds change too slowly the meanings are nailed emotionally to the old ways, and culture stagnates.

This statement is a controversial issue, and indeed, it may sound puzzling. Doesn"t culture direct language changes or is the language the driving force of cultural evolution? Direct experimental evidence is limited; it will have to be addressed by future research. Theoretical considerations suggest no neural or mathematical mechanism for culture directing evolution of language through generations; just the opposite, most of cultural contents are transmitted through 