Table 3.
Studies of cognition in dystonia.
| Author, Year | Study Type | Sample Size | Findings | Neuro-psychologic al tests | Comments |
|---|---|---|---|---|---|
| Eldridge, 1970 | Case control | 14 autosomal recessive dystonia 10 siblings 24 controls |
Stastitically significant increase in IQ scores for patients affected with autosomal recessive dystonia | IQ test | |
| Taylor, 1991 | Case control | 20 idiopathic focal dystonia 20 healthy controls |
Only explicit memory, speed of information processing affected by high dose anticholinergics | NART, WAIS-R, LP, VR, DRT, TT, BSRT, CALT, BC, Item 99 from LNNB, SCWT, VFT, WCST | Vulnerability to meds highly age dependent |
| Hinse, 1996 | Case control | 15 spasmodic torticollis 15 normal controls |
ST pts performed significantly worse on spatial tasks requiring mental manipulation of personal space | MW, HRDT, CBTT, VST | No significant difference in spatial perception |
| Ghilardi, 1999 | Case control | 4 non-manifesting carriers of DYT 1 5 healthy controls |
NMC pts had significantly decreased scores for motor and visual sequence learning than HC group | ME, MSL, VSL | |
| Ghilardi, 2003 | Case control | 12 non-manifesting carriers of DYT 1(no hx of psychiatric disease) 12 healthy controls |
Sequence learning impaired in carriers with preserved motor performance | CCW, RAN, SEQ | Overactivation of left PMC, right SMA in NMC patients during sequence learning (PET scan). May be compensating for striatal dysfunction |
| Jahanshahi, 2003 | Case control | 10 idiopathic focal dystonia + idiopathic generalized dystonia 12 healthy controls |
Significant difference in category fluency and performing dual tasks. Otherwise, preserved executive fxn compared to controls | NART, WFT, WCST, SCWT, MDT, SORNS, RNG, VVCAL, PVSAT, DTP | Only 1/10 pts on meds (4 mg Artane/day), dystonia group had nonsignificant increase in self reported depression |
| Scott, 2003 | Case series | 14 primary dystonia (7 men, 7 women) prior to undergoing GPi deep brain stimulation surgery | Baseline impairment with extradimensional set-shifting (prior to DBS surgery), part of CANTAB battery | CANTAB, NART, Raven, SDMT, Stroop, TM, BNT, JLO, SCOLP, RMT, AMIPB, DS, CF | Not clear if this impairment is functionally significant, or if it improves with GPi surgery. Study not controlled for mood, pain, meds |
| Balas, 2006 | Case control | 20 manifesting carriers of DYT1 8 non-manifesting carriers of DYT1 28 matched controls |
Symptomatic pts performed better on semantic verbal fluency test, worse on verbal learning test | Raven, RAVLT, RCF, PVF, SVF, TMA/B, Stroop, CANTAB, WAIS-III, JLO, PP | No difference between nonsymptomatic carriers and controls. Statistically accounted for meds, anxiety levels |
| Pillon, 2006 | Longitudinal cohort | 22 primary generalized dystonia undergoing DBS surgery | No pre-surgical cognitive decline in executive function. GPi DBS mildly but significantly improved executive fxn. | Raven, WAIS-R, GBT, WCST, VFT, TMA/B | Improvement either related to DBS or reduction in anticholinergic drugs. 20/22 pts on meds prior to surgery |
| Allam, 2007 | Case control | 9 primary cranial dystonia (blepharospasm) 9 healthy controls |
Sustained attention deficits prior to botox injections; following injections, no significant difference in sustained attention compared to controls | RAVLT, TPT, DSub, DSY, SCWT | Executive dysfxn may be related to disrupting effects of symptoms |
| Bugalho, 2008 | Case control | 45 idiopathic focal/segmental dystonia 27 healthy controls |
More set-shifting deficits in dystonia group, also had significantly more obsessive compulsive symptoms | WCST, SCWT, BAT, BVRT | No pts on anticholinergic medication |
| Carbon, 2008 | Case control | 6 non-manifesting carriers of DYT1 6 healthy controls |
NMC pts performed at control levels during sequence learning | TSEQ, CCW | NMC pts overactivated lateral cerebellum, R inferotemporal cortex, underactivated prefrontal regions |
| Aleman, 2009 | Case control | 20 blepharospasm 17 healthy controls |
BL pts showed impairment of complex movement planning, motor dexterity, visuospatial working memory, and tactile object recognition | WAIS-III, FDT, Raven, LT, LOW I/II, SL, WCST, PP, OMT, DR, TD, Tap | Groups matched for severity of depression and education level |
AC- anticholinergic; BC-Block Counting Item from Stanford-Binet Intelligence Test; AMIPB- Adult Memory and Information Processing Battery; BAT- Block Assembly Test of WAIS; BL-blepharospasm; BNT- Boston Naming Test; BSRT- Buschke Selective Reminding Test; BVRT- Benton Visual Retention Test; CALT- Conditional Associative Learning Test; CANTAB- Cambridge Neuropsychological Test Automated Battery; CBTT- Corsi’s Block Tapping Test; CCW- matched motor baseline task; CF- Medical College of Georgia Complex Figures; CLTR- Consistent Long-Term Memory; DR- Digital Recognition; DRT-Delayed Recognition Span Test; DS- Digit span; DSub- Digit Subtest of Wechsler Memory Scale-R; DSY- Digit Symbol subtest of the Wechsler Intelligence Scale-R; DTP- dual task performance; FDT- Five Digits Test; GBT- Grober and Buschke test; HC- healthy controls; HRDT- Hebb’s Recurring Digits Test; IFD-idiopathic focal dystonia; IGD-idiopathic generalized dystonia; HC-healthy controls; JLO-judgment of line orientation; LNNB-Luria-Nebraska neuropsychological battery; LOW I/II- List of Words I and II; LP- Logical Passages; LT- Luria task; MC-manifesting carriers; MDT- missing digit test; ME- motor execution; MSW- motor sequence learning; MW- Mehrfachwahl-Worschatztest; NART- National Adult Reading Test; NMC-non-manifesting carriers; OMT- Oral Making Trails; PET-positron emission tomography; PMC- premotor cortex; PP- Purdue pegboard; PVF- phonemic verbal fluency; PVSAT- Paced Visual Serial Addition Test; RAN – reaction time/motor performance; Raven- Raven’s Matrices; RAVLT- Rey auditory verbal learning test; RCF- Rey complex figure; RMT- Recognition Memory Test; RNG- random number generation; SCOLP- Speed and Capacity of Language Processing test; SCWT-Stroop Colour-Word Test; SDMT- Simple Digit Modalities Test; SEQ – motor learning task; SL- Spatial Location; SMA- supplementary motor area; SORNS-Self-Ordered Random Number Sequences; SVF- semantic verbal fluency; Tap- Tapping Test; TD- Tactile Denomination; TMA/B- Trail-making A and B; TPT- Toulouse-Pieron Test; TSEQ – trial-and-error-guided motor sequence learning task; TT-Tower of Toronto Test; VFT-Verbal Fluency Test; VR-Visual Reproduction; VVCAL- Visual-Visual Conditional Associative Learning; VSL- visual sequence learning; VST- Visuospatial testing; WAIS-R – Wechsler Adult Intelligence Scale-revised; WAIS-III- Wechsler Adult Intelligence Scale-III; WCST-Wisconsin Card Sorting Test; WFT-word fluency test;