What are the different theories about how the brain processes speech? When we heard speech the brain needs to go through a series of steps to go from the received sounds to a mainly conceptual meaning that follows from the words involved. This involves solving a series of problems along the way like moving from sounds into phonemes, then to words and to sentences, to a possibly holistic meaning of the whole speech. How does the brain solves this problem?

I was told there are many theories, but I don't have any names, except what some people call "the oscillatory theory of speech perception" of which I could not find much literature. Do anyone know books and papers that cover this topic, presenting different theories of speech perception, including this "oscillatory" theory?

I will greatly appreciate any linked books and papers.
This question is quite broad and since it seems to be basically a reference request, I will suffice by giving some prominent theories of speech perception with sources and references.

Speech perception theories are grouped into two:


Passive (or non-mediated) theories. These theories mostly focus on finding the identity of certain constant perceptual cues and on the ways the auditory system might extract them from the acoustic signal. These theories are basically filtering theories, and do not involve the mediation of higher cognitive processes in the extraction of these cues. It is assumed that acoustic cues are extracted in the periphery of the auditory system (source: Mannell).
Active (or mediated) theories. These theories suggest that there is no direct relationship between the acoustic signal and the perceived phoneme, but that higher level processes are involved instead that compare input patterns with internal patterns (source: Mannell).


Passive theories


The distinctive feature theory defines a set of acoustic and articulatory features that is used to generate a binary code system of yes/no decisions to allow the identification of speech sounds at a phonemic level (source: Mannell).
The acoustic theory is also based on a set of distinctive features that are largely production based. The distinctive features are assumed to be encoded directly, and passively in the periphery of the auditory system (source: Mannell).


Active theories


The motor theory (or analysis-by-synthesis) assumes that perception and production are closely linked and that motor commands in the brain that control movements of the muscles used to speak, also help us to perceive speech. It claims that humans are equipped with an innately present speech processing 'module' (sources: UC Calgary, Mannell, Libermann &amp; Mattingly (1985)).
The trace theory assumes that there are 3 connected speech perception levels - features, phonemes and words. Facilitation of these levels is assumed to occur through connections between the levels (source: UC Calgary).


Reference
- Libermann &amp; Mattingly Cognition (1985); 21: l-36