Cognitive function in HSPers

Mild impairment is widespread

Cognitive functions, including social cognition should be systematically assessed in HSPers to improve clinical management.

“Brain fog” is how one HSPer describes his mental state as he can no longer concentrate as well as he used to, or for as long.

The nine SPAST (SPG4) HSPers in this French study averaged 52 years old and had HSP symptoms for an average of 16 years. The study found:

  • no intellectual disability or dementia
  • all have mild cognitive impairment including attention deficit
  • 90% have executive function disorders, affecting goal formation, planning, goal-directed action, changing goals, switching focus, self-monitoring and attention or focus, amongst others
  • 80% have impaired social cognition, which can be thought of as the brain’s capability applied to social situations, including expressing emotions and noticing the emotions of others, as well as the ability to understand the potential mental states and intentions of others
  • one HSPer, who shows no physical symptoms but carries a known SPAST mutation, shows mild cognitive impairment just like the others
  • no correlation was found between mental and physical impairment, age of onset of HSP, or disease duration
  • cognitive disorders might sometimes occur before motor disorders.


To describe cognitive assessment including social cognition in SPG4 patients.


We reported a series of nine patients with SPG4 mutation with an extensive neuropsychological examination including social cognition assessment.


None of our patients presented with intellectual disability or dementia. All presented with mild cognitive impairment with a high frequency of attention deficit (100%), executive disorders (89%), and social cognition impairment (78%). An asymptomatic patient for motor skills presented with the same cognitive profile. No correlation was found in this small sample between cognitive impairment and motor impairment, age at disease onset, or disease duration.


SPG4 phenotypes share some cognitive features of frontotemporal lobar degeneration and amyotrophic lateral sclerosis. Cognitive disorders including executive disorders and social cognition impairment are frequent in SPG4 patients and might sometimes occur before motor disorders. Therefore, cognitive functions including social cognition should be systematically assessed in order to improve the clinical management of this population.

SOURCE: Behav Neurol. 2016;2016:6423461. Epub 2016 Sep 4. PMID: 27688599 PMCID: PMC5027053 DOI: 10.1155/2016/6423461

Cognitive Impairment Involving Social Cognition in SPG4 Hereditary Spastic Paraplegia.

Chamard L1, Ferreira S1, Pijoff A2, Silvestre M1, Berger E1, Magnin E1.

1 University Hospital of Besançon, CH Jean Minjoz, Besançon, France.

2 Regional Hospital of Dole, CH Louis Pasteur, Dole, France.

Your email address will not be published. Required fields are marked *