amytal test

Twelve of the patients had right hemisphere speech representation as determined by the Wada sodium amytal test.

There remains the sodium amytal test which is accurate but suitable only for use with candidates for brain surgery.

Levy's computations ignore the data from the sodium amytal test which suggest that at least some proportion of left handers have speech represented bilaterally.

Volpe, Sidtis and Gazzaniga (1981) observed four left handed patients who had been given the Wada Sodium Amytal test.

As these figures are identical to those given for the Amytal test by Rasmussen and B. Milner (1975) it is presumably these data to which he refers).

This proportion is very much higher than estimates based on the effect of unilateral cerebral lesions or the Amytal test (but see Wexler, Halwes and Heninger, 1981).

With the proviso that such patients may have atypical cerebral organisation for speech the amytal test provides the best estimate we have of speech lateralisation in left and mixed-handers.

While a mean right ear advantage has been correlated with left hemisphere dominance for speech as determined by the Wada sodium amytal test (Kimura, 1961a; Tsunoda, 1975) the validity of dichotic ear asymmetry as an index of cerebral speech representation in individual subjects is questionable.

No one has suggested that all left handers have bilateral representation of speech but the distribution of speech representation in sinistrals can be estimated on the grounds of the Amytal test as 70 per cent left sided, 15 per cent right sided and 15 per cent bilateral.