Agneta Herlitz

Gender differences in episodic memory

The relationship between gender and memory has been largely neglected by research, despite occasional studies reporting gender differences in episodic memory performance. The present study examined potential gender differences in episodic memory, semantic memory, primary memory, and priming. Five hundred thirty women and 470 men, randomly sampled from the city of Umeå, Sweden, 35–80 years of age, participated in the study. There were no differences between men and women with regard to age or education, or on a measure of global intellectual functioning. As has been demonstrated previously, men outperformed women on a visuospatial task and women outperformed men on tests of verbal fluency. In addition, the results demonstrated that women consistently performed at a higher level than did men on the episodic memory tasks, although there were no differences between men and women on the tasks assessing semantic memory, primary memory, or priming. The women’s higher level of performance on the episodic memory tasks could not be fully explained by their higher verbal ability.

Nerve growth factor affects11C-nicotine binding, blood flow, EEG, and verbal episodic memory in an Alzheimer patient (Case Report)

SummaryBased on animal research suggesting that nerve growth factor (NGF) can stimulate central cholinergic neurons, the known losses of cholinergic innervation of the cortices in Alzheimers disease (AD), and our experience of infusing NGF to support adrenal grafts in parkinsonian patients, we have initiated clinical trials of NGF infusions into the brain of patients with AD. Here we report a follow-up of our first case, a 69-year-old woman, with symptoms of dementia since 8 years. Intraventricular infusion of 6.6 mg NGF during three months resulted in a marked transient increase in uptake and binding of11C-nicotine in frontal and temporal cortex and a persistent increase in cortical blood flow as measured by PET as well as progressive decreases of slow wave EEG activity. After one month of NGF, tests of verbal episodic memory were improved whereas other cognitive tests were not. No adverse effects could be ascribed to the NGF infusion. Taken together, the results of this case study indicate that NGF may counteract cholinergic deficits in AD, and suggest that further clinical trials of NGF infusion in AD are warranted.

Sex differences in face recognition—Women’s faces make the difference

Sex differences favoring women have been found in face recognition tasks as well as in verbal episodic memory tasks. Womens higher face recognition performance was hypothesized to be related to either their higher verbal ability or to their superiority in recognizing female faces, rather than faces in general. Results showed that whereas there were no differences between men and women in the recognition of male faces, or in verbal ability, women performed at a higher level than men in the recognition of female faces. Verbal ability did not influence womens face recognition performance. Potential explanations for this pattern of data, such as sex differences in interest and prior knowledge, are discussed.

Sex differences favoring women in verbal but not in visuospatial episodic memory

Sex differences favoring women have been found in a number of studies of episodic memory. This study examined sex differences in verbal, nonverbal, and visuospatial episodic memory tasks. Results showed that although women performed at a higher level on a composite verbal and nonverbal episodic memory score, men performed at a higher level on a composite score of episodic memory tasks requiring visuospatial processing. Thus, men can use their superior visuospatial abilities to excel in highly visuospatial episodic memory tasks, whereas women seem to excel in episodic memory tasks in which a verbalization of the material is possible.

Sex Differences in Episodic Memory

Research shows sex differences in episodic memory. These differences vary in magnitude as a function of the type of material to be remembered. Throughout the life span, verbal episodic-memory tasks yield differences favoring women. In contrast, episodic-memory tasks requiring visuospatial processing result in differences favoring men. There are also sex differences favoring women on episodic-memory tasks requiring both verbal and visuospatial processing and on face-recognition tasks. Thus, there may be a small, general episodic-memory advantage for women—an advantage that can increase by the advantage women have over men in verbal production and can be reversed by the male advantage in visuospatial tasks. In addition, environmental factors affect the magnitude of the sex differences in episodic memory.

Cognitive predictors of incident Alzheimer's disease: a prospective longitudinal study.

The present study examined whether cognitive variables measured at baseline could predict incident cases of Alzheimers disease (AD) after a 3-year follow-up period. Twenty-six incident AD adults and 179 very old (M = 83.5 years) adults without dementia participated in a population-based study. Cognitive performance was indexed by the Mini-Mental State Examination (MMSE) and multiple indices of memory and visuospatial and verbal performance. A logistic regression analysis that controlled for age, gender, and education indicated that MMSE scores were reliable indicators of who would develop AD. In addition, recall of organizable words, recognition of faces, and letter fluency were reliable predictors of subsequent dementia status after differences in MMSE performance were partialed out. Thus, although the MMSE is useful in predicting dementia, there is an additional advantage of assessing specific indices of cognitive functioning. Further, supportive episodic memory tasks may be more salient predictors of incident AD than tasks that offer less supportive encoding or retrieval conditions.

Intracranial infusion of purified nerve growth factor to an Alzheimer patient : the first attempt of a possible future treatment strategy

We report on the clinical outcome of a first case of intracranial infusion of nerve growth factor (NGF) to an Alzheimer patient. The therapeutic attempt is based on animal research showing that NGF stimulates central cholinergic neurons of the type known to be lost during the development of Alzheimers disease (AD). Furthermore, our own previous clinical experience of infusing NGF to support the survival of intracranially transplanted adrenal chromaffin cells to Parkinsonian patients indicate this approach to be technically possible and safe and clinically of significant potential. Our first case was a 69-year-old woman, with symptoms of dementia since 8 years. Intraventricular infusion of 6.6 mg NGF over three months resulted in a marked transient increase in uptake and binding of [11C]nicotine in frontal and temporal cortex and a persistent increase in cortical blood flow as measured by PET as well as progressive decreases of slow wave EEG activity. After one month of NGF infusion, tests of verbal episodic memory were improved whereas other cognitive tests were not. No adverse effects of the NGF infusion were found. The results of this single case indicate that NGF may counteract cholinergic deficits in AD, and suggest that further clinical trials of NGF infusion in AD are warranted.

The association between endogenous free testosterone and cognitive performance : A population-based study in 35 to 90 year-old men and women

The relationship between testosterone (T) and cognition has yielded conflicting evidence, showing both positive and negative influences of T on cognitive performance. The association between free testosterone (FT) and cognition was revisited in a large population-based sample of 1276 women and 1107 men (35-90 years of age), assessed individually on visuospatial, verbal fluency, semantic, and episodic memory tasks. For men, higher FT levels were associated with better visuospatial abilities, semantic memory, and episodic memory, with greater positive influence with increasing age. Statistical covariates included age, education, and select medications. For women, FT was negatively associated with verbal fluency, semantic memory, and episodic memory, although only verbal fluency was significant at conventional alpha levels. These results support the claim that FT exerts sex-specific influences on cognitive performance.

Sex Differences in Cognition are Stable Over a 10-Year Period in Adulthood and Old Age

ABSTRACT Sex differences in declarative memory and visuospatial ability are robust in cross-sectional studies. The present longitudinal study examined whether sex differences in cognition were present over a 10-year period, and whether age modified the magnitude of sex differences. Tests assessing episodic and semantic memory, and visuospatial ability were administered to 625 nondemented adults (initially aged 35–80 years), participating in the population-based Betula study at two follow-up occasions. There was stability of sex differences across five age groups and over a 10-year period. Women performed at a higher level than men on episodic recall, face and verbal recognition, and semantic fluency, whereas men performed better than women on a task-assessing, visuospatial ability. Sex differences in cognitive functions are stable over a 10-year period and from 35 to 90 years of age.

Higher face recognition ability in girls: Magnified by own-sex and own-ethnicity bias

Earlier studies on adults have shown sex differences in face recognition. Women tend to recognise more faces of other women than men do, whereas there are no sex differences with regard to male faces. In order to test the generality of earlier findings and to examine potential reasons for the observed pattern of sex differences, two groups of Swedish 9-year-old children (n = 101 and n = 96) viewed faces of either Swedish or Bangladeshi children and adults for later recognition. Results showed that girls outperformed boys in recognition of female faces, irrespective of ethnicity and age of the faces. Boys and girls recognised Swedish male faces to an equal extent, whereas girls recognised more Bangladeshi male faces than boys did. These results indicate that three factors explain the magnitude of sex differences in face recognition: an overall female superior face recognition ability, the correspondence between the sex of viewer and the gender of the face, and prior knowledge of the ethnicity of the face.