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Neyda Ma Mendoza-Ruvalcaba, Elva Dolores Arias-Merino, María Elena Flores-Villavicencio, Melina Rodríguez-Díaz and Irma Fabiola Díaz-García Neyda Ma Mendoza-Ruvalcaba, Elva Dolores Arias-Merino, María Elena Flores-Villavicencio, Melina Rodríguez-Díaz and Irma Fabiola Díaz-García Additional information is available at the end of the chapter

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.71551

#### **Abstract**

The study of cognitive function in gerontology is considered relevant because it is an important risk factor for other pathologies in the old age, such as physical disability and dependence, depression, and frailty, mainly because of early pathological changes in cognitive function which are considered a preclinical state that may progress to dementia. In this chapter, cognitive functioning and the dimensions that are included in it (attention, memory, meta-memory, processing speed, executive functions, visuospatial skills, and language) are conceptualized. Additionally, the current evidence is analyzed regarding age-associated changes that are experienced during cognitive aging. These changes, or cognitive decline, are distinguished from those that are part of cognitive pathologies, the most common mild cognitive impairment and dementia. Such pathologies are conceptualized based on the current diagnostic criteria, and controversies and challenges are discussed. Additionally, we analyze the risk factors for cognitive functioning in aging, both modifiable and nonmodifiable ones. A review of the main nonpharmacological intervention techniques used from the gerontology approach is made. It includes the cognitive training in the case of age-related decline or techniques of stimulation and cognitive rehabilitation in the case of mild cognitive impairment or dementia. Finally, we conclude with an analysis of the current state of this topic in the field of gerontology and its relevance in professional practice.

DOI: 10.5772/intechopen.71551

**Keywords:** cognitive aging, age-related decline, mild cognitive impairment, dementia, cognitive intervention

#### **1. Introduction**

Population aging is a global reality that is happening in a gradual and unavoidable manner, as a result of the low birth rate and mortality in the population, and at the same time, due to

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

the increase in life expectancy. However, aging is not only a population phenomenon but also an individual reality [1], which involves a series of changes in people at biological, psychological and social levels. In the psychological field, changes in the domains related to personality, affectivity, emotions, emotional control, and interpersonal relationships have been reported [2].

Cognitive functioning has been defined as an evolutionary process in which individuals are immersed, which begins in fertilization and ends in death. In this process, both the organism in general and the nervous system in particular experience a series of changes that, in interaction with the environment, enable the development and maturation of both the nervous

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http://dx.doi.org/10.5772/intechopen.71551

A more integrative view of mind-brain relationships defines the cognitive functions as functional interactions within and among cortical networks, which in turn are distributed throughout the cerebral cortex as memory, attention, perception, language, and intelligence;

From another perspective, cognitive functions come from the information processing activity in neural networks distributed along the cortex and represent past and future schemes of action. This perspective suggests that temporal organization affects perceptual processes,

From a psychopedagogical framework, complex cognitive functions consist of the organizing and sequencing of plans, the ability to respond to various stimuli at the same time, cognitive flexibility, the ability to respond according to the context, resistance to distraction, and inhibi-

From Piaget's theoretical position, cognitive functions are considered as the mechanisms of information processing, which main function is to transform the internal and external stimuli into inputs for development and, in addition, to provide the individual with tools to face the positive entropy, and also the trend to exhibit states of thermodynamic equilibrium [12].

From the point of view of the structural cognitive modifiability theory, the cognitive functions are classified as perceptual thinking (basic functions), strategic (executive functions), analogical (educational functions), and reflexive (meta-cognitive functions) according to the

Finally, from the neuropsychology perspective, the different components of cognitive functions are defined as the abilities developed by brain structures that allow them to work with the information that is acquired from the environment. These cognitive abilities are divided into two groups: those known as basic cognitive functions such as sensation, perception, memory, attention and concentration; and higher cognitive functions such as thought, language, and intelligence, which are considered complex systems and also group different functions [14].

During the last decades, several scientific efforts have been focused on the study of normal cognitive aging. This has resulted in agreements, as well as numerous discrepancies around the topic, mostly regarding the use of different research methodologies, as well as the little control of other variables that are considered to be closely related to cognitive functioning.

In addition, finding differences between normal cognitive aging and a cognitive impairment involving pathology is clinically difficult, since the limits of diagnosis are not precise.

action, and cognition within a sequence designed to achieve a goal [10].

system itself and the behavior [9].

all sharing the same structure [4].

tion of inappropriate behaviors [11].

**2. Age-associated changes**

last generation of the constructivism paradigm [13].

Regarding cognitive functioning, the changes that occur during aging are of increasing interest for gerontology because of the implications they could have in case they finally appear in their most pathological form: dementia.

Historically, the research of cognitive functions has its epistemological origin in the studies carried out by the philosopher Galenus, who argued that in the ventricles of the brain, the consciousness of the human being was found as a set of different capacities: perception, intellect, and memory. From the philosophy of Rene Descartes (1596–1650) arises the neurophysiological theory, which defined the relationship between body and spirit and tried to find the explanation of mental function in the ventricles as the basis of psychic functions, later setting the pineal gland as related to mental disorders.

Later, Flourens (1794–1867) argued that all neural tissues are involved in the different cognitive functions. But it was until Gall's studies (1758–1828) with his Frenology theory, that on one side, cognitive functions were associated with structures by examining the skull, and on the other side, the role of the cerebral cortex in relation to cognitive functions was presented. It was until the nineteenth century, with the establishment of the neuropsychology, when the correlation of anatomo-clinical structures with the alterations in cognitive functions was clearly set up [3, 4].

During the nineteenth century, the first stage of neuropsychology was established. Its study object is the relationship between the cerebral organization and the behavior in its broadest sense: actions, emotions, motivations, and social relations. The unit of analysis of neuropsychology is the individual, including his personal history, and his social and cultural environment. The founders of this approach are Luria, Vygotsky, and Leontiev, with the concern of locating psychological functions within circumscribed parts of the brain, defined higher mental human functions as complex reflex-like processes of social origin whose functioning is both conscious and voluntary and are possible due to their structure and functioning [5]. Later, in 1981, Luria proposed that cognitive functioning analysis should be done by looking for what is located outside the individual, the place where the origins of conscious activity are found. He also developed the idea that several macroanatomical areas and brain regions help each other to ensure control of the so-called human cognitive functions [6]. The cognitive psychology perspective studies the cognitive functioning as the way to know the world, through the construction of reality guided by experience. From there, the cognitive structure is formed and the concept of a cognitive scheme arises [7].

Piaget's theory can be found under this perspective, where the study of structures is left aside to focus on the development of cognitive functioning and its schemes, from a constructive approach of knowledge that at the same time disproves empiricists and innatists theories, based on a psychogenetic perspective [8].

Neuropsychology is a discipline with an integrative view, which today contributes decisively to our knowledge about how the brain and the alterations of its functioning work, focused on the cognitive development in relation to sociocultural factors.

The conceptualization of cognitive functioning functions had several meanings.

Cognitive functioning has been defined as an evolutionary process in which individuals are immersed, which begins in fertilization and ends in death. In this process, both the organism in general and the nervous system in particular experience a series of changes that, in interaction with the environment, enable the development and maturation of both the nervous system itself and the behavior [9].

A more integrative view of mind-brain relationships defines the cognitive functions as functional interactions within and among cortical networks, which in turn are distributed throughout the cerebral cortex as memory, attention, perception, language, and intelligence; all sharing the same structure [4].

From another perspective, cognitive functions come from the information processing activity in neural networks distributed along the cortex and represent past and future schemes of action. This perspective suggests that temporal organization affects perceptual processes, action, and cognition within a sequence designed to achieve a goal [10].

From a psychopedagogical framework, complex cognitive functions consist of the organizing and sequencing of plans, the ability to respond to various stimuli at the same time, cognitive flexibility, the ability to respond according to the context, resistance to distraction, and inhibition of inappropriate behaviors [11].

From Piaget's theoretical position, cognitive functions are considered as the mechanisms of information processing, which main function is to transform the internal and external stimuli into inputs for development and, in addition, to provide the individual with tools to face the positive entropy, and also the trend to exhibit states of thermodynamic equilibrium [12].

From the point of view of the structural cognitive modifiability theory, the cognitive functions are classified as perceptual thinking (basic functions), strategic (executive functions), analogical (educational functions), and reflexive (meta-cognitive functions) according to the last generation of the constructivism paradigm [13].

Finally, from the neuropsychology perspective, the different components of cognitive functions are defined as the abilities developed by brain structures that allow them to work with the information that is acquired from the environment. These cognitive abilities are divided into two groups: those known as basic cognitive functions such as sensation, perception, memory, attention and concentration; and higher cognitive functions such as thought, language, and intelligence, which are considered complex systems and also group different functions [14].
