Table 2.
Areas of neurodegeneration and their correlations with functional domains/measures.
| Study | Participants (Relative to clinical diagnosis) | Area of neurodegeneration | Correlated functional domain/measure |
|---|---|---|---|
| Douaud et al. (32) | Clinically diagnosed HD | Caudate (indicated by both manual segmentations and VBM) | Motor (Purdue pegboard®, UHDRS-TMS, Hand-arm test), cognitive (Symbol Digit Modalities Test), everyday functioning (TFC) |
| Douaud et al. (32) | Clinically diagnosed HD | Putamen, globus pallidus (indicated by both manual segmentations and VBM) | Motor (Purdue pegboard®, UHDRS-TMS) |
| Jech et al. (40) | Clinically diagnosed HD | Caudate, internal capsule, occipital lobes, cerebellum, brainstem (VBM) | Motor (UHDRS-TMS) |
| Bechtel et al. (41) | Before HD clinical motor diagnosis, Clinically diagnosed HD | Caudate, putamen, superior temporal, precentral, internal/external capsule, subgyral frontal white matter (VBM); Occipital, parietal, and primary motor cortical thickness | Finger tapping (variability of tap durations and inter-onset intervals) |
| Scahill et al. (42) | Before HD clinical motor diagnosis, Clinically diagnosed HD | Striatal, occipital (VBM) | Quantitative motor (tongue force), oculomotor (anti-saccade error rate) |
| Starkstein et al. (44) | Clinically diagnosed HD | Caudate, frontal, and left sylvian cistern atrophy | Memory/speed-of-processing (based on factor analysis of neuropsychological test scores) |
| Peinemann et al. (45) | Clinically diagnosed HD | Caudate (VBM) | Executive function (Tower of Hanoi, STROOP, modified Wisconsin Card Sorting Test) |
| Bäckman et al. (49) | Clinically diagnosed HD | Frontal region volume | Memory, executive function (Trail Making Test—part B, Rey-Osterrieth Complex Figure—memory, Word Recall, Perseverative Errors) |
| Aylward et al. (50) | Clinically diagnosed HD | Frontal lobe volume, frontal lobe gray and white matter volume | General cognitive functioning (Mini Mental State Examination, general verbal and spatial ability)–the correlations did not survive correction for overall brain volume loss |