Table 1.
Summary of differences between SD and SA patients
| Symptom | SD | SA |
|---|---|---|
| Lesion | Bilateral anterior temporal | Left prefrontal/ temporoparietal |
| Verbal comprehension | Poor | Poor |
| Non-verbal comprehension | Poor | Poor |
| Consistency/task correlations | ||
| Within task | ✓ | ✓ |
| Between task | ✓ | ✗ |
| Effect of phonemic cueing | ✗ | ✓ |
| Familiarity/frequency effects across tasks | ✓ | ✗ |
| Strong effect for requirement of semantic control | ✗ | ✓ |
| Associative semantic errors in picture naming | ✗ | ✓ |
See Jefferies and Lambon Ralph (2006) for further detail.