RESUMO
Two experiments tested the effect of temporal interference on order memory for fixed and random sequences in young adults and nondemented older adults. The results demonstrate that temporal order memory for fixed and random sequences is impaired in nondemented older adults, particularly when temporal interference is high. However, temporal order memory for fixed sequences is comparable between older adults and young adults when temporal interference is minimized. The results suggest that temporal order memory is less efficient and more susceptible to interference in older adults, possibly due to impaired temporal pattern separation.
Assuntos
Envelhecimento/fisiologia , Atenção/fisiologia , Memória de Curto Prazo/fisiologia , Aprendizagem Seriada/fisiologia , Adolescente , Idoso , Comportamento de Escolha , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Tempo de Reação/fisiologia , Estatísticas não Paramétricas , Fatores de Tempo , Adulto JovemRESUMO
We examined performance of healthy older and younger adults and individuals with Alzheimer's disease (AD) and Parkinson's disease (PD) on digit cancellation, a task putatively sensitive to cognitive impairment, but possibly affected by visual impairment, particularly in contrast sensitivity. Critical contrast thresholds were established to create custom stimulus arrays that were proximally matched across individuals. Age- and PD-related differences in search were fully accounted for by the sensory deficit. Increased contrast benefited AD patients, but could not override cognitive impairment. We conclude that visually fair neuropsychological testing can effectively compensate for normal age- and PD-related visual changes that affect cognitive performance.
Assuntos
Envelhecimento/fisiologia , Doença de Alzheimer/fisiopatologia , Sensibilidades de Contraste/fisiologia , Doença de Parkinson/fisiopatologia , Transtornos da Visão/fisiopatologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos/normas , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico , Sensibilidade e Especificidade , Transtornos da Visão/complicações , Transtornos da Visão/diagnóstico , Adulto JovemRESUMO
Young and nondemented older adults were tested on a continuous recognition memory task requiring visual pattern separation. During the task, some objects were repeated across trials and some objects, referred to as lures, were presented that were similar to previously presented objects. The lures resulted in increased interference and an increased need for pattern separation. For each object, the participant was asked to indicate whether (1) this was the first time the object was seen (new), (2) the object was seen previously (old), or (3) the object was similar to a previous object (similar). Older adults were able to correctly identify objects as old or new as well as young adults; however, older adults were impaired when identifying lures as similar. Therefore, pattern separation may be less efficient in older adults resulting in poorer recognition memory performance when interference is increased.
