Can the Right Hemisphere Mediate Language as Well as the Left? A Critical Review of Recent Research
The “anti-equipotentiality” hypothesis maintains that language cannot develop as well in the right as in the left hemisphere after lateralised brain damage, even if the brain damage is sustained very early in life before the child has started to speak. Out of eight papers published on this topic between 1980 and 1986, seven claim to support the anti-equipotentiality view However, only one of these papers provides data which fulfil normal scientific criteria, i.e., adequate numbers for statistical analysis and appropriate control data, and the results from this study are discrepant with those obtained by other researchers using the same measures. The remaining papers either present results which are uninterpretable, because of small sample sizes and lack of normative data, or, in some cases, provide data supporting the equipotentiality position. It is concluded that no satisfactory evidence against equipotentiality has yet been published. © 1988, Taylor & Francis Group, LLC. All rights reserved.