Cognitive and affective neuroscience: approaches and applications

KEYWORDS:

• Emotion
• language
• bilingual
• long-term potentiation
• forensic
• flexibility
• EEG
• transcranial magnetic stimulation

Cognitive and affective neuroscience are the disciplines that draw on neuroscientific evidence to further our understanding of cognitive processes like memory, language, attention, and consciousness; and of affective processes like emotion, empathy, and motivation. For this special issue, we invited cognitive and affective neuroscientists from across New Zealand to share their research and their expertise. The resulting nine articles reflect the many methods used across our universities, ranging from animal models, to cutting-edge neuroimaging approaches, to the study of changes associated with aging, criminal activity, and bilingualism. They also cover a diverse range of research questions, from fundamental processes of learning and memory, to the nature of consciousness itself.

Sateesh and Abraham (2021) describe basic preclinical research on the role of the hippocampus in memory consolidation. The review focusses on the phenomenon of long-term potentiation, an increase in synaptic efficacy, that is produced following a brief period of electrical stimulation of the hippocampus. They review electrophysiological, biochemical and molecular tools that are used to study synaptic plasticity using this model. They also discuss genetic, receptor and pharmacological mechanisms underlying the induction and expression of long-term potentiation. A description of potential mechanisms of disruption to long-term potentiation in various neurological conditions and the potential to apply this basic information to treatment approaches is also provided.

Kirk et al. (2021) provides evidence to support the proposal that ‘LTP-like’ changes in EEG-derived human visual evoked potentials have the same characteristics (and are thus driven by the same mechanisms) as long-term potentiation (LTP) studied in experimental animals. The ability of to measure LTP mechanisms in humans allows for the exploration of the role of synaptic plasticity in human memory and other cognitive processes. This ability also allows for the direct study of synaptic plasticity in a number of human disorders (e.g. schizophrenia, depression, Alzheimers) in which LTP has been proposed to be atypical.

Eisenbarth (2021) reviews the literature on forensic neuroscience and describes the way that neuroscience can help to inform the causes and consequences of criminal behaviour. This paper provides an excellent foundation of the approaches. A description of how various neuroscience methods have been, and are being, applied to the study of some components of criminal behaviour is provided. As an example, a potential link between cognitive empathy and violent behaviour is presented. Examples of the use of various neurophysiological methods to understand and potentially modify violent behaviour are discussed.

Hamm (2021) explores the nature of research, including the interplay between theoretical, methodological, and data areas (which he refers to different types of research ‘space’). For example, psychological research is unable to control all aspects of methodological space, as individual participants always bring in uncontrolled values (e.g. their own personal level of visual sensitivity, word familiarity, etc). Hamm uses Illusory Line Motion as an example of this, discussing why we see motion when none exists under different circumstances.

Waldie et al. (2021) reviews whether there is a cognitive advantage to bilingualism and whether the bilingual brain is different in terms of both executive functioning and lexical decision-making. She focuses on two of her functional MRI studies, where task performance and brain activation from late proficient bilinguals (when using their first and second languages) are compared to monolinguals. She concludes that learning a second language after age 6 years may confer a benefit to executive functioning but at the expense of decreased cortical efficiency.

Highgate and Schenk (2021) review the animal and human literature on cognitive/behavioural flexibility. The review is intended to inform the non-specialist. They provide an overview of the most commonly used procedures including diagrams to facilitate understanding, highlight how procedures used in humans have been adapted for study in non-human animals and provide a brief description of the neurobiological mechanisms. They point out how deficits in behavioural flexibility contribute to a number of different disorders.

Machado (2021) takes a lifespan perspective to study changes in cognition that occur with healthy aging and brain disease, and to show how those changes can be mitigated by lifestyle choices such as diet, exercise, and volunteering. She and her colleagues have used near-infrared spectroscopy (NIRS), a portable technology that allows researchers to identify brain networks that are activated during complex cognitive tasks. Her research shows that these networks change across the lifespan, with recruitment of more anterior and bilateral networks compensating for age-related declines.

Bareham et al. (2021) use transcranial magnetic stimulation (TMS) to determine how brains create conscious experience. In contrast to neuroimaging methods, which can identify brain activity that is correlated with conscious awareness, TMS can be used to temporarily disrupt brain function, allowing researchers to draw causal inferences about this relationship. In their review, they address two distinct questions about consciousness: how our brains create transitions between the states of sleep and wakefulness, and how neural activity determines the contents of our awareness at any moment in time. Although this research is still in its infancy, Bareham and colleagues show how new methodological approaches are shedding light on age-old problems.

Our nervous systems extend beyond the brain. Grimshaw and Philipp (2021) take their research into the periphery, showing how activity in the autonomic and somatic nervous systems can be used to address questions about social and emotional processes. They provide a primer on the primary paradigms used in psychophysiological research, and demonstrate how these methods have yielded insights on conscious awareness, emotion regulation, and the social functions of smiles.

Disclosure statement

No potential conflict of interest was reported by the author(s).