Can new neurons replace memories lost?

It now appears that new neurons are produced not only in the healthy adult brain but also in the brains of patients with Alzheimer's disease (AD). Although the function of new neurons in the healthy brain is unknown, there is evidence that they are involved in certain types of memory formation and that their survival is enhanced dramatically and persistently by learning experiences. The evidence that neurogenesis, or at least the expression of proteins unique to immature neurons, occurs during the late stages of AD raises the possibility that their production could be enhanced earlier in the disease process before so many neurons and memories are lost.     

Creating new neurons in old brains

The brains of aged rodents exhibit decreased neurogenesis as compared to those of young adult rodents. Basal neurogenesis has previously been shown to increase in the young adult rodent brain upon the administration of growth factors. However, it is unknown whether similar treatment can affect this process in the aging brain. A recent paper published in the June 2003 issue of the journal Aging Cell reveals that two growth factors can stimulate neurogenesis in aged mice. This result raises the possibility that similar treatments may be used in humans to help maintain normal brain function in old age.     

Embodied cognitive neuroscience and its consequences for psychiatry

Recent years have seen the emergence of a new interdisciplinary field called embodied or enactive cognitive science. Whereas traditional representationalism rests on a fixed inside–outside distinction, the embodied cognition perspective views mind and brain as a biological system that is rooted in body experience and interaction with other individuals. Embodiment refers to both the embedding of cognitive processes in brain circuitry and to the origin of these processes in an organism’s sensory–motor experience. Thus, action and perception are no longer interpreted in terms of the classic physical–mental dichotomy, but rather as closely interlinked. This paper describes the cycles of brain–organism interaction, of sensory–motor interaction with the environment and of embodied interaction with others. The brain is then interpreted as an organ of modulation and transformation that mediates the cycles of organism–environment interaction. Finally, consequences of the embodied and enactive approach for psychiatry are pointed out, in particular for a circular concept of mental illness.     

Estrogen treatment affects brain functioning after menopause

Sex hormones have powerful neuromodulatory effects on functional brain organization and cognitive functioning. This paper reviews findings from studies investigating the influence of sex hormones in postmenopausal women with and without hormone therapy (HT). Functional brain organization was investigated using different behavioural tasks in postmenopausal women using either estrogen therapy or combined estrogen plus gestagen therapy and age- and IQ-matched postmenopausal women not taking HT. The results revealed HT-related modulations in specific aspects of functional brain organization including functional cerebral asymmetries and interhemispheric interaction. In contrast to younger women during the menstrual cycle, however, it seems that HT, and especially estrogen therapy, after menopause affects intrahemispheric processing rather than interhemispheric interaction. This might be explained by a faster and more pronounced age-related decline in intrahemispheric relative to interhemispheric functioning, which might be associated with higher sensitivity to HT. Taken together, the findings suggest that the female brain retains its plasticity even after reproductive age and remains susceptible to the effects of sex hormones throughout the lifetime, which might help to discover new clinical approaches in the hormonal treatment of neurological and psychiatric disorders.     

An examination of the mechanisms underlying the effects of physical activity on brain and cognition

Physical activity positively influences brain health and cognitive functioning in older adults. Several physiological and psychological mechanisms have been identified to underlie such a relationship. Cardiovascular fitness is accompanied with changes in mechanisms such as cerebral blood flow, neurotrophic factors, neurotransmitter systems and neural architecture that have themselves been associated with cognitive performance. Factors associated with exercise such as arousal, mood and self-perception of competence seem also to influence cognitive performance. Other explanation for the benefits of exercise in cognition, results from the fact that the performance of motor skills involve an important cognitive component (e.g., executive functions and information processing speed). Evidence of brain plasticity and behavior has been provided from studies where animals are exposed to enriched or complex environments. Exposure to such paradigms in which physical activity plays an important role has been found to influence various aspects of brain function and structure. Studies using neuroimaging techniques have established a link between the acquisition of different motor skills and the occurrence of neuroplasticity in human adults. This literature review indicates that the type of exercise and its specific perceptual and cognitive characteristics may influence cognitive performance. However, most of the research has been focused on self-paced movements or automatized skills and few intervention studies have examined the results of merging exercise and cognitive training in a single program. An important scientific challenge for the coming years is to design exercise programs capable of mobilizing several type of mechanisms underlying the effects of physical activity on brain and cognition.     

Computing brains: learning algorithms and neurocomputation in the smart city

ABSTRACT

This article examines IBM’s ‘Smarter Education’ program, part of its wider ‘Smarter Cities’ agenda, focusing specifically on its learning analytics applications (based on machine learning algorithms) and cognitive computing developments for education (which take inspiration from neuroscience for the design of brain-like neural networks algorithms and neurocomputational devices). The article conceptualizes the relationship between learning algorithms, neuroscience, and the new learning spaces of the city by combining the notion of programmable ‘code/space’ with ideas about the ‘social life of the brain’ to suggest that new kinds of ‘brain/code/spaces’ are being developed where the environment itself is imagined to possess brain-like functions of learning and ‘human qualities’ of cognition performed by algorithmic processes. IBM’s ambitions for education constitute a sociotechnical imaginary of a ‘cognitive classroom’ where the practices associated with data analytics and cognitive computing in the smart city are being translated into the neuropedagogic brain/code/spaces of the school, with significant consequences for how learners are to be addressed and acted upon. The IBM imaginary of Smarter Education is one significant instantiation of emerging smart cities that are to be governed by neurocomputational processes modelled on neuroscientific insights into the brain’s plasticity for learning, and part of a ‘neurofuture’ in-the-making where nonconscious algorithmic ‘computing brains’ embedded in urban space are intended to interact with human cognition and brain functioning.     

Basic‐Level Categories,Mirror Neurons,and Joint‐Attention Schemes: Three Points of Intersection Between G.H. Mead and Cognitive Science

Recent research in cognitive science has provided broad empirical support for the model of cognition and self‐development formulated by G.H. Mead. This is demonstrated specifically through three distinct cognitive mechanisms: basic‐level categories, mirror neurons, and joint‐attention schemes. These mechanisms illustrate a form of embodied sociality that underscores the intersubjective foundation of mind and self articulated by Mead. Research on basic‐level categories, mirror neurons, and joint‐attention schemes further extends Mead's relevance outside standard sociological and social psychological circles to the field of cognitive science and its emerging focus on sociality and social interaction.     

Cognitive function in toddlers with congenital heart disease: The impact of a stimulating home environment

Infants born with congenital heart disease (CHD) are at increased risk of neurodevelopmental difficulties in childhood. The extent to which perioperative factors, cardiac physiology, brain injury severity, socioeconomic status, and home environment influence early neurodevelopment is not clear. Sixty-nine newborns with CHD were recruited from St Thomas’ Hospital. Infants underwent presurgical magnetic resonance imaging on a 3-Tesla scanner situated on the neonatal unit. At 22 months, children completed the Bayley Scales of Infant and Toddler Development-3rd edition and parents completed the cognitively stimulating parenting scale to assess cognitive stimulation at home. Level of maternal education and total annual household income were also collected. Hospital records were reviewed to calculate days on the intensive care unit post-surgery, time on bypass during surgery, and days to corrective or definitive palliative surgical intervention. In the final analysis of 56 infants, higher scores on the cognitively stimulating parenting scale were associated with higher cognitive scores at age 22 months, correcting for gestational age at birth, sex, and maternal education. There were no relationships between outcome scores and clinical factors; socioeconomic status; or brain injury severity. Supporting parents to provide a stimulating home environment for children may promote cognitive development in this high-risk population.     

The “fetus-infant”: Changing classifications ofIn Utero development in medical texts

This paper examines several aspects of the changing cultural classifications of reproduction through a close reading of obstetrics textbooks. Through the discursive construction of the fetus in obstetric texts, medical accounts are beginning to classify the fetus as a baby. In investigating this transformation, I focus upon two cognitive processes: the splitting of the fetus apart from the pregnant woman and the concurrent lumping of two distinct mental entities—a fetus and an infant into one new medical category: the fetus-infant. In addition, textual evidence shows a shift in cognitive orientation away from classifying fetuses based on gestational age to an emphasis on what I term functional age. Further, new knowledge enables physicians to affect functional age, making the fetus with mature function in utero conceptually no different from a baby. An earlier version of this paper was presented at the American Sociological Association Meeting, Washington, DC, August, 1995.     

Cognitive,social, and neural determinants of diminished decision-making and financial exploitation risk in aging and dementia: A review and new model

ABSTRACT

In this article we will briefly review how changes in brain and in cognitive and social functioning, across the spectrum from normal to pathological aging, can lead to decision-making impairments that increase abuse risk in many life domains (e.g., health care, social engagement, financial management). The review will specifically focus on emerging research identifying neural, cognitive, and social markers of declining financial decision-making capacity in older adults. We will highlight how these findings are opening avenues for early detection and new interventions to reduce exploitation risk.     

Does physical exercise improve perceptual skills and visuospatial attention in older adults? A review

Neuroimaging studies suggest that when the brain ages, more areas are involved to perform a task in order to obtain the same results. This, together with the increase in crystalized intelligence and wisdom, is usually considered as a compensatory strategy. Research has demonstrated that physical activity might also act as a strategy and be one of the main factors that can slow down age-related perceptual and cognitive decline. Research also suggests that different types of physical exercise and sport lead to different changes in perceptual and cognitive skills as well as in several areas of the brain, especially those involving multiple domains, such as exergaming, dance or some sports. This review summarizes the findings of recent studies with older adults investigating the brain and cognitive benefits of different forms of physical exercise. Visuospatial attention, which plays a critical role in our daily lives, especially for older adults, is a central part of this analysis.     

The urban neighborhood and cognitive functioning in late middle age

This study examines the association of cognitive functioning with urban neighborhood socioeconomic disadvantage and racial/ethnic segregation for a U.S. national sample of persons in late middle age, a time in the life course when cognitive deficits begin to emerge. The key hypothesis is that effects of neighborhood on cognitive functioning are not uniform but are most pronounced among subgroups of the population defined by socioeconomic status and race/ethnicity. Data are from the third wave of the Health and Retirement Survey for the birth cohort of 1931 to 1941, which was 55 to 65 years of age in 1996 (analytic N = 4,525), and the 1990 U.S. Census. Neighborhood socioeconomic disadvantage has an especially large negative impact on cognitive functioning among persons who are themselves poor, an instance of compound disadvantage. These findings have policy implications supporting "upstream" interventions to enhance cognitive functioning, especially among those most adversely affected by neighborhood socioeconomic disadvantage.     

The problem of being a paradigm: the emergence of neural stem cells as example for “Kuhnian” revolution in biology or misconception of the scientific community?

In a thought experiment we want to test how the emergence of adult neural stem cells could constitute an example for a scientific revolution in the sense of Thomas Kuhn. In his major work, “The structure of scientific revolutions, 3rd edn, University of Chicago Press, Chicago” (Kuhn 1996), the philosopher of science, Thomas Kuhn, states that scientific progress is not a cumulative process, but new theories appear by a rather revolutionary sequence of events. Kuhn built his theory on landmark events taken from chemistry and physics, lacking examples from biology. Beginning with Ramon y Cajal’s famous quote, “no new neurons after birth”, from the early years of the twentieth century, and Reynolds and Weiss’s conflicting finding in 1992 of adult neural stem cells giving rise to new neurons, we will test how the finding of neural stem cells in the adult brain matches with Kuhn’s theory. The pivotal problem of defining a paradigm will be our main focus, since the emergence of adult neural stem cells has been acclaimed by the scientific community as the rebuttal of Ramon y Cajal’s paradigm.     

Lipofuscin and aging: a matter of toxic waste

Lipofuscin is membrane-bound cellular waste that can be neither degraded nor ejected from the cell but can only be diluted through cell division and subsequent growth. The fate of postmitotic cells is to accumulate lipofuscin, which as an "aging pigment" has been considered a reliable biomarker for the age of cells such as neurons and, by extension, their hosts. In the aging human brain, deposits of lipofuscin are not uniformly distributed but are concentrated in specific regions of functional interest. The prevailing thought is that the major source of lipofuscin is incomplete lysosomal degradation of damaged mitochondria. Accumulating evidence suggests that lipofuscin is not benign but can impair the functioning of seemingly unrelated cellular systems, including the ubiquitin/proteasome pathway. A damaging feedback loop of lysosomal and proteasomal inhibition may occur as lipofuscin accumulates, leading to what has been appropriately named a "garbage catastrophe." Reversing this catastrophe presents a formidable challenge.     

Dementia with cerebrovascular disease

In this case study, we review the symptoms, cognitive testing, brain imaging, and brain pathology of a woman with dementia, for whom the neuropathological findings suggest a prominent contribution of cerebrovascular disease. Vascular dementia is the term commonly used for persons with dementia resulting from strokes, either clinically evident or subclinical "silent" events. "Mixed dementia" is the term used when there is an admixture of pathological findings related to Alzheimer's disease (AD) and cerebrovascular disease, as in this situation. In some cases of mixed dementia, the pathological involvement of AD may be the principal contributory cause of the cognitive symptoms, and in others, the vascular changes may give the greater contribution.     

亚健康试试推拿(英文)

现代社会发展迅速,人们的社会压力、心理压力不断增加,使机体常常处于疲劳状态.大脑、内脏器官就会出现功能失调或功能减退,或机体组织结构老化变快,这种没有疾病而又有自我不适的状态被称为亚健康状态。推拿疗法为治疗亚健康提供了一种有效的保健手段,它具有中医疗法的优越性——简便有效、易为人接受。推拿治疗的过程,让人感觉到机体的轻松、心情的舒畅。     

Triadic balance in the brain: Seeking brain evidence for Heider’s structural balance theory

Structural balance theory is a foundational theory of social network research. Despite enduring interest in seeking network evidence for the theory, the fundamental question of why people care about structural (im)balance has received relatively little attention. The original answer to the question, dating back to Heider’s work six decades ago, is that structural imbalance causes a person to experience cognitive dissonance and sentimental disturbance. In this paper, we used a state-of-the-art neuroimaging technique to test the argument. Our study shows that individuals’ psychological states, evidenced by the activation of brain areas, are different when they are situated in unbalanced rather than balanced triads. More specifically, the differences in the brain activation between triadic imbalance and balance were found in brain regions known for processing cognitive dissonance, as discovered by previous research. Our study provides novel brain evidence in support of Heider’s original account for the psychological and biological foundations of structural balance theory in the formation of social networks.     

Two sources of human irrationality: Cognitive dissonance and brain dysfunction

Akerof and Dickens explored the relevance of cognitive dissonance theory for economics, and the theory is shown here to predict occasional irrational thinking. Secondly, it is proposed that the focus of neuroeconomics on brain dysfunction and the role of neurotranmitters on cognition suggests two ways in which the functioning of the brain can impair rational decision-making.     

Cognitive and behavioural assessment of people with traumatic brain injury in the work place: occupational therapists' perceptions

Cognitive and behavioural impairments, in the absence of severe physical disability, are commonly related to poor return to work outcomes for people with traumatic brain injury (TBI). Along with other health professionals, occupational therapists make judgements about cognitive and behavioural dimensions of work capacity of clients with TBI during the return to work process. Unlike many physical functional capacity evaluations, there is no standard method that therapists use to assess the ability of people with TBI to perform cognitive operations required for work. Little is known about what information occupational therapists use in their assessment of cognitive and behavioural aspects of client performance within the work place. This study employed qualitative research methods to determine what information is utilised by 20 therapists who assess the work capacity of people with TBI in the workplace. Results indicated that the process of making judgements about cognitive and behavioural competence within the work place is a multifaceted process. Therapists triangulate client information from multiple sources and types of data to produce an accurate view of client work capacity. Central to this process is the relationship between the client, the job and the work environment.     

Visual metaphors of living with brain injury: exploring and communicating lived experience with an invisible injury

Brain injury can affect cognitive, emotional and physical functioning – consequences that pose challenges to understanding survivors' perspectives on their lives. Furthermore, the injury may be invisible, even clinically, causing additional confusion for affected individuals, family members, co-workers and clinicians. The present study used photovoice with adult brain injury survivors so they could communicate their lived experience. Participants took photographs, discussed them, and selected some for captions. Half of their selected images are visual metaphors that foster a multifaceted view of brain injury with room for negative as well as positive aspects of their experience. Photovoice provided opportunities to communicate a personal voice during group discussions and in study binders, and a group voice in outreach products. Visual metaphors became vehicles for voice as participants used photovoice to make visible their brain injuries and their efforts to wrestle with the impacts and discover new purpose and meaning in life.