There is good behavioral evidence coming from a famous study done on barn owls (Knudson & Knudson, 1989). In case you're unfamiliar with the experiment, baby barn owls were reared from birth with binocular prisms that displaced the visual field by varying degrees to the right. When visual targets were shown, head orientation was shifted to the right of the targets by the same amount as the prismatic displacement. When auditory stimuli were given, the same result was shown. Furthermore, when the prisms were removed, although orientation to visual targets were comparable to that of normal owls, sound localization errors remained. Thus, "owls use vision to calibrate associations of auditory localization cues with locations in space".

A clear distinction needs to be made adults and infancy, since adult models, eg of aphasia after stroke, do not apply to infants whose cortical systems are undeveloped and need to be imprinted or reprogrammed from sensory input.   The best models for developmental sensory deprivation are congenital blindness and deafness.  There are many anatomic and imaging studies showing subsequent cortical reorganisation in humans. 

Thanks Anthony. I'm trying to find out this info in the context of profound hearing loss, such as the case of someone who uses both sign language and spoken language, equally competently. Im currently an auditory neurophysiology student, doing a Masters in EEG type investigations into cochlear implants in adults. I'm also a CI user myself. My question that sparked this, was the educational sector division over either doing intense auditory therapy for CI children or taking a bilingual approach. The thing is, the two languages are also bi-modal - they are using completely different inputs at the sensory level, and completely different areas of the brain. My question is how did that example i gave earlier of a very competent signer and very competent speaker, exist, and its at odds with my admittedly very small, understanding of neuroplasticity and cortical reorganisation  Its a very sensitive topic, as many people are either one side or the other. I'm beginning to believe its purely about the therapy and type of input, but i have nothing to back that up in terms of literature.

Eric - thank you for the reference and story - i was aware of the Weisell cat vision experiments with just visual plasticity, but your example seems to cover cross-modal as well.

please go to the research of Rick van Dijk in Plos one: Haptic spatial configuration in Deaf and Hearing individuals (april 2013)Full tekst on line\and from the same author: Superir touch : improved haptic orientation preocessing in deaf individuals. Experimetnal brain research October 2013

"my admittedly very small, understanding of neuroplasticity and cortical reorganisation Its a very sensitive topic"

And a very confusing one.  When there was first talk of introducing cochlear implants, I did not think these were likely to succeed, and did not get involved in this area of audiology.  This was based on my understanding of cortical plasticity at the time.   I thought that someone born with very little hearing had learned to compensate, to extract idiosyncratic clues from the residual degraded and distorted auditory input.  A CI would then supply a third form of input, different to both normal hearing and the defective version.  So the person would have to unlearn all the strategies and tricks learnt from dealing with the defective input from birth, and all the brain connections for auditory analysis would have to be overriden and reprogrammed.   As things have turned out, this line of reasoning must have been faulty.

You may want to see this article on misophonia and the interaction between visual and auditory stimulation on ERPs.  You might find the influences between the stimuli to be of interest.   Gerdes ABM, Wieser MJ, Bublatsky R, et. al. (2013).  Emotional sounds modulate early neural processing of emotional pictures.  Frontiers in Psychology, October, 4: 741, doi 10.3389/fpsyg.2013.00741.

 "I don't have an article in mind to corroborate that"

I have wondered for a long time if acquisition of language 2 helps or hinders language 1. There seem to be a remarkable lack of good data pertaining to this, such that I put up a question on RG as to whether bilinguality raised or lowered IQ.   I have still not seen much definitive research in deaf or hearing populations.  

Anu Sharma has done some research in this area with regard to age of initial implantation.

"I have wondered for a long time if acquisition of language 2 helps or hinders language 1. There seem to be a remarkable lack of good data pertaining to this, such that I put up a question on RG as to whether bilinguality raised or lowered IQ."

The thing with bilingualism in IQ tests, often are only one language is being "measured". Same for language tests etc. To get a proper picture, both languages need to be assessed. Problem is standardised tests are often based on a particular language eg English, and cant simply translate - would have to get standardized again for that language.

With two spoken languages, its shown that different patterns of language "competency" emerge depending on if simultaneous acquisition or sequential acquisition. Its the problem of "is this child delayed, disordered, or some other factor?". Assessing say language 1 only, for a simultaneous acquisition bilingual child would be a poor test. But it wouldnt be a poor choice of testing for a sequential acquisition bilingual child.

Tricky bit with my original question is the two languages are different modes, and are equally languages, but at sensory level things like prosody in speech are visually communicated in some aspect of  how a Sign is conveyed, which is solidly in the visual domain of the brain. Adding a whole separate layer of complexity on top of the bilingual considerations as well.

So i was trying to approach by neurophysiology instead of language

Laura Ann Pettito has done some fantastic research on the neurophysiology of hearing loss and acquisition of language

Anyone know of any emerging ideas in topic, given that I asked three years ago now ?

I looked into Pettito's work at the time, but could only find white papers from their lab website, and not peer reviewed articles? Is this still the case or has that work emerged into the scientific literature now? I wasn't convinced by the white papers entirely but it had some interesting concepts and rationales, and gave me for for thought for several weeks at that time. Might revisit :)

Might be following paper is helpful

Article Behavioural phenotypes in the cuprizone model of central ner...