Language is affected by internal and external input.
The internal input refers to all the cognitive and physical processes that take place during human communication.
Making sense of what you hear, processing it, and then responding back by decoding.
When we decode, we need not only our brain processes, but our actual ability to produce sounds and voice letters.
- Cognitive/Physical condition-
People with aphasia, or any other physical or mental propensity that threatens language fluency, will also create problems processing language. Any problems processing language also means problems reproducing it. In not so many words, if you cannot hear properly the language that you are going to be speaking, you will be losing valuable key points in intonation, cadence, timbre, and prosody (not to mention fluency and semantic meaning).
To this list, it is important to add:
- chronological age versus developmental age -not all individuals develop language skills at the same rate
- trauma or any psychological impediment - these can affect language development directly
The external input refers to the language that we learn from others, as we imitate, replicate, or use it for different purposes. This would be how we use language at work, for cultural identity grouping, socially, or academically.
There are two types of language, according to Krashen (1987): Natural language, which is produced automatically, and monitor language, which is the one we use "for specific occasions". The outside input (external) has as much power as the internal when it comes to producing and developing specific language for different things.
Parents who do not engage in active conversations with their children lose them both cognitively and linguistically...and psychologically. Parents are the primary models of language development in children. They teach them how to talk, they are supposed to teach them new words, and even read to their children on a daily basis.
Since our current society may or may not operate this way in general, what we are seeing today in schools are kids with major language and comprehension gaps. Also, kids with terrible listening skills. This is because early exposure through proper communication patterns with family members and caregivers did not occur in the first place. This not the only cause for the gaps, but it is definitely one of many.
- Social setting-
Close-knit communities, cultural subgroups, even small coalitions, use their own language code to communicate. It is part of the sense of identity that they want to achieve as a group. Words acquire different semantics in those scenarios. The context is not the same. If the style of speech is used as an indicator of personality, or of belonging, it will affect all the members of the entire group the same way.
- Needs basis
This goes back to the theories of motivation and learning proposed by Garner (1989), and Krashen (1987). Motivation and goals play a key role in language usage. If the right motivation is in, and there is a goal at hand that entails language usage of any kind, the result will be that language will be undoubtedly affected by those two factors.
Example: If there is motivation to use language erroneously (like in gangs, street jargon, etc.) and there is a goal for that (belonging to a cool crowd, an initiation into a subgroup) then the results will affect language negatively.
The same thing can happen on the positive side, where students can be rewarded for using language properly. In that case, the result will be that the language usage and development will be influenced in a good way.