In examining the behaviours of consumers, researchers look for explanations, drivers and motives. The fields of economics and psychology approach consumer decision making through key concepts, some overlap but the theories may differ in their points of view on the related processes and effects. Marketing, consumer behaviour and behavioural economics borrow and integrate concepts from both fields. However, their models of decision processes could be missing or overlooking deeper underlying biological mechanisms that may provide genuine explanations of the origins of human behaviour, especially in decision making. A salient argument arising from this perspective addresses the possibility that two apparently distinct processes or effects are actually produced by the same biological mechanism. Furthermore, the mechanism or driver could be evolutionary, developed in the junction between biology (e.g., physiology, genes) and the environment, with a focus particularly on adaptation.

Neuroscience receives a special place in reviews and discussions of this school of research with regard to decision making from the perspectives of biology and evolution. Two sub-areas of specialisation can be particularly identified. From the side of biology, there is main focus on neurobiology, that is biology of the nervous system, primarily the brain (i.e., the central nervous system); biology of the brain concerns its physical structure and functions, and more specifically types of neuronal cells, component structures and systems, and associated neural activities. From the side of economics, there is increased research interest in the emerging conjoint field of neuroeconomics, concerning the potential contributions of neuroscience to explaining (and predicting) behaviour in economic contexts. (Similarly emerging is the specialised sub-field of consumer neuroscience, linked more closely to consumer behaviour and marketing.) The influences conceived from the perspectives of biology and evolution may attain to consumer behaviour more broadly in a wide range of contexts, yet the research addressed here deals mostly with decision making, information processing and choice.

In the latest edition of the Behavioral Economics Guide (2026), Isabelle Brocas [1] reviews and explains in an article on the biological foundations of decision making how biological mechanisms may operate ‘behind the scenes’ of judgement and choice decisions, beyond familiar concepts and phenomena from economics and the behavioural sciences. She further lays out a model that combines the impact and effects of psychological (primarily cognitive), biological (especially neural) and environmental variables and concepts on (consumer) decision making.

Studies of behaviour recognise distinct domains such as risk, intertemporal choice, self-control, social preferences, memory, attention, belief formation, and strategic sophistication. However, we may not find through them adequate answers on how consumers reach their decisions. While these domains have analytic value, they should not be confused with the “natural architecture of the mind” (i.e., they do not ascribe to separate modules in the brain). Additionally, preferences are recognised as a foundation of choice decisions. Yet, their value as “final explanations” of choices could be limited. Brocas does not suggest dismissing the role of preferences, rather treating preferences as summaries of stable choice patterns, and as “compact descriptions of behavior generated by deeper processes” (p. 3). There is the key in approach to preferences as well as cognitive concepts or domains as listed above: by recognising the deeper biological processes that enable their execution, and moreover the interactions between those processes: “Economic behavior arises from interacting biological processes, including perception, attention, memory retrieval, valuation, affective appraisal, inhibition control, and action selection” (p. 3).

The model proposed by Brocas for a biologically informed framework of decision making (Figure 1 in her article) identifies three ‘layers’: ‘biological’, ‘cognitive’ and ‘behavioural’. It should be noted, however, that the boundaries between them are not rigid. Economic behaviour emerges from interactions between the cognitive processes, which are shaped by the “biological endowments and environmental conditions”. In the ‘top layer’ of biology and the environment we find antecedents such as stress, genetic endowments, social conditions and early environment. The ‘mid layer’ comprises concepts or processes that are essentially cognitive, including perception, attention, memory, affect, valuation and self-regulation. In the ‘bottom layer’ of economic behaviour appear risk-taking, trust, intertemporal choice, cooperation, strategic reasoning, and consumer choice. The chart depicts links of influence among concepts from the ‘biological layer’ to ‘cognitive layer’ and from the ‘cognitive layer’ to ‘behavioural layer’ (one exceptional feedback stream ‘flows up’ from risk back to the environment). Conspicuously, Consumer Choice is shown isolated (no links). The conceptual model is also shown in a different form of a network (Figure 2 by Brocas) which suggests inter-relations between a mixture of neurobiological, cognitive and emotional processes and the decision-making behaviours they influence (e.g., intertemporal choice, memory-based choice).

• Comment: Cognitive concepts and processes (mental) are described also as biological mechanisms and processes. This ‘dual’ presentation apparently aims to note that the mental processes are actually driven by underlying biological mechanisms (e.g., neural systems and processes) that enable their operation and execution. The confound between levels is indeed conceivable yet not elucidated enough in the article and hence can be confusing to readers.

Researchers can find multiple opportunities for studying and analysing various decision processes in different situations. In such studies one should enquire about the bases of the more familiar and apparent concepts and constructs, where there may operate by common underlying biological or neural mechanisms. For example, Brocas refers to preferences for risk (uncertainty) and time (delay). They are usually regarded as separate constructs, until we consider mechanisms that may underlie both types of decisions (e.g., valuation, affective anticipation, learning from feedback, inhibitory control). Relatedly, risk-loving and impatience seem to be different forms of behaviour, yet in a person inclined to be impulsive they can be linked because both involve common patterns of reward sensitivity, limited future simulation, stress, or weaker self-regulation. When behaviour changes across contexts or when response to external interventions may vary across individuals, traditional economic construct are less useful explanations; thence we need to look deeper to account for the behaviour of agents (e.g., consumers). First, researchers may look for the underlying concepts or mechanisms (mental, biological) that different types of behaviours share. Second, they may seek to identify which of those deeper mechanisms have a stronger impact in shaping a behaviour of a certain type to explain observed differences.

The handling of choice problems by consumers can be approached through a neuroeconomic model of value-based choice, developed by Rangel, Camerer and Montague (2008, [2]) and advocated by Brocas; wherein a choice decision process comprises a succession of sub-processes of computations performed in the brain. It starts with representation of the problem, followed by the valuation of actions (considering internal and external states), then choosing an action based on those valuations, and subsequently evaluation of the outcomes following the action taken, thereon updating, based on this learning, the first three sub-processes. Brocas suggests that the logic of this neural-based process framework provides further impetus to rejecting the treatment of risk, time, social choice and self-control as self-contained domains. Another theme followed by Brocas, based on her previous work with colleagues, is seeing choice decision tasks as constrained optimisation problems. That is, human cognitive resources are limited and therefore the brain allocates and manages them under constraints of their availability (e.g., memory retrieval, attention, valuation, self-control) with respect to characteristics of the choice task.

As mentioned above, neurobiology is under main focus. From the broader perspective of biology, nevertheless, we may be called upon to account for organs and systems in other parts of the body, their functions and processes, that may be implicated during decision making. Consider, for example, the feelings of stomach nervousness, faster heart pace and a difficulty to catch one’s breath that are often experienced in situations that evoke tension, anxiety or anger. Of particular relevance are interactions between the brain and body while transferring information bi-directionally.

Somatic markers, as proposed by Antonio Damasio, are bodily sensations or subtle feelings that signal to the human’s brain a predicted future outcome of an action to notice before making a decision — similar to the function of gut feeling. Damasio defined somatic markers as “a special instance of feelings generated from secondary emotions” (p. 174, italics in origin [3], secondary emotions are acquired). A predicted outcome, constructed through learning, can be negative, whereby the somatic marker serves as an “alarm bell”, or positive, whereby the somatic marker acts as a “beacon of incentive”. Accordingly, a somatic marker, as a bodily signal, may serve an important role as a corrective internal intervention in a decision process of reasoning and rational thinking. Brocas [1] refers to how learning from past outcomes helps in “marking some options more salient, dangerous, or attractive than others”. She sees the value of somatic markers in “identifying a process by which past experience, bodily state, affective appraisal, and valuation interact to shape action” (p. 10). Brocas directs us, nonetheless, also to other areas beyond the neuroscientific perspective (or neuroeconomics), and which can be related to biology, including genetics, developmental science, endocrinology, psychiatry, and modelling of internal resource constraints.

The analysis and appraisal of decision-making behaviours may not be complete without taking into account issues such as heterogeneity, personality and emotion — usually not in the purview of economics. Differences between individuals can be found in personality, developmental history and environments in which individuals have grown up. Genes and the environment take part in shaping personality traits and other aspects of brain functions, and these will consequently affect patterns of decision making. Additionally, cognition and emotion have to be regarded as working in tandem, side-by-side and interactively (e.g., signalling, contemplating and regulating), in the course of making decisions.

The viewpoint of evolution introduces us to plausible roots of differences in behaviour of humans overall, as consumers in particular, and with regard to other animal species as well. The evolution-oriented explanations may be based on differentiations between individuals (e.g., biological, physiological, neural) and changes in environmental conditions (e.g., physical, social, cultural); these could have developed over many years and following events that occurred a very long time ago. Griskevicius and Durante (2015, [4]) propose an evolutionary approach to consumer behaviour, based on two founding tenets: (1) “All human behavior includes an evolutionary explanation“, and (2) “Evolutionary explanations concern the adaptive function of behavior” (emphases added). They deal mainly with cases of consumer choices.

• Griskevicius and Durante describe (following Tinbergen) four types of explanation of behaviour: Proximate Mechanism (immediate causes), Development (Ontogeny), Ultimate Function (adaptation), Evolutionary History (Phylogeny). The third type on which they concentrate addresses the question: “What adaptive problem(s) does a behavior ultimately function to solve?” — the ultimate functions are derived from their explanation of how the behaviour enhanced fitness and increased the chances of survival and success throughout evolutionary history (e.g., babies cry because this behaviour proved a reliable way to elicit care, like food or holding, from a caregiver). The authors suggest, however, that each type of explanation can make a valued contribution to the analysis, hence it is best advised to combine explanations from the different perspectives complementarily.

Mismatch theory helps us to understand gaps between the function of behaviour that developed adaptively to the ancestral environment and the function or implication of a similar behaviour in our modern-day environment. It corresponds to a gap between the pace of evolution of the brain which may take thousands of years and the more rapidly changing environment (especially since the industrial revolution and the technological race thereon). It is therefore even harder for the human brain to produce adaptive behaviours that comply effectively with changes in conditions and means during shorter periods (on a scale of a few centuries to decades) in recent times. For example, human affinity to sugar (e.g., in chocolate cakes) and fats was borne out of facing scarcity of nutrients and calories in ancient times, but such ingredients are abundant in food in modern society particularly in developed countries, and hence this behaviour leads to increase in incidence of Obesity and Diabetes.

Griskevicius and Durante discuss implications of fundamental motives. Beyond goals of survival or reproduction, as indicators of “evolutionary success”, or even nourishment and shelter, we should look further at social motives. The authors address different challenges humans have had to confront since ancestral times: (1) evading physical harm; (2) avoiding disease; (3) making friends; (4) attaining status; (5) acquiring a mate; (6) keeping a mate; and (7) caring for a family. This perspective seems to have provided Griskevicius and Durante a fertile ground to explore and discuss a range of contemporary behaviours with respect to these motives. They give interesting examples of differences in behaviour — for instance, between men and women in their use of products (e.g., luxury, perfumes, fashion), whether for attracting a mate (men) or retaining a mate (women). Yet, even for a given individual, actions and choices may vary, sometimes even inconsistently, between periods and according to their current fundamental motive. They consider specifically behavioural changes among women during the ovulatory cycle (i.e., the Ovulatory Shift Hypothesis). The authors consider the different kinds of products men and women might use to signal their value to a mate (men: jewellery, designer clothes, exotic vacations; women: cosmetics, botox, diet plans) and what strengths they would want to signal (men: commitment, willingness and ability to invest in a mate; women: youth & fertility). They recommend further research on spending and consumption behaviour in relationships, particularly the romantic ones, and family life, with an eye on influencing factors from an evolutionary perspective.

• A Sidenote: If we take a step backwards from humans in the pathway of evolution, some cognitive phenomena specified in behavioural economics (e.g., biases, framing effects, preference reversal, risk and reward discounting) have been found in research to be exhibited in nonhuman primates, the animal species phylogenetically closest to us. This would indicate that their occurrence may require just basic, elementary cognitive abilities that exist in both nonhuman primates and humans alike, although their manifestation in primates could be more limited (e.g., the endowment effect restricted to food items). Santos and Rosati (2015, [5]) argue that “if psychologists want to truly understand human decision making, we should also be interested in the evolutionary origins of decision-making biases”.

Biology and evolution are not commonly accepted or adopted perspectives as yet in the contexts of consumer behaviour and decision making, from a marketing orientation or economic orientation (e.g., behavioural economics). Knowledge from the perspectives of biology and evolution can enlighten our understanding of how decision processes emerge and build-up from biological mechanisms and processes, with emphasis on neurobiology, and may be explained through long-lasting evolutionary factors. They involve complementary or interactive relations (e.g., between brain and body, cognitive processes and the underlying biological mechanisms, cognition & emotion) in shaping consumer choice behaviour. Notwithstanding, greater clarification of the inter-relations and effects between the cognitive, neural and biological processes and systems is required. Consequently, the unique contributions of adopting the biological as well as evolutionary perspectives should be marked more lucidly to encourage their employment in the economic and marketing contexts. Hence, there is substantive reason to motivate continued research and studying consumer decision making and choices in these routes.

Ron Ventura, Ph.D. (Marketing)

References:

[1] Beyond Preferences: The Biological Foundations of Decision-Making (Editorial); Isabelle Brocas, 2026; The Behavioral Economics Guide, pp. 2-15, BehaviouralEconomics.com

[2] A Framework for Studying the Neurobiology of Value-Based Decision Making; Antonio Rangel, Colin Camerer, & P. Read Montage, 2008; Nature Reviews (Neuroscience), Vol. 9 (July), pp. 545-556 (available at Rangel Neuroeconomics Lab, California Tech Institute, CalTech)

[3] The Somatic Marker Hypothesis (Chapter 8); Antonio Damasio, 1994; Descartes’ Error: Emotion, Reason, and the Human Brain, Penguin Books

[4] Evolution and Consumer Behavior (Chapter 5); Vladas Griskevicius and Kristina M. Durante, 2015; in The Cambridge Handbook of Consumer Psychology (Editors M.I. Norton, D.D. Rucker, & C. Lamberton) [pp. 122-151], Cambridge University Press

[5] The Evolutionary Roots of Human Decision Making; Laurie R. Santos and Alexandra G. Rosati, 2015; Annual Review of Psychology, Vol 66, pp. 321-347