Thalamus and Hypothalamus

Both the thalamus and hypothalamus play an important role in emotional experiences (LeDoux, 1996;

Papez, 1937, cited in Gluck et al., 2020), which is why we will look at them in more detail again in

Chapter 3.

The thalamus can be referred to as the “gateway to the cortex” because it receives and processes

sensory and regulatory input from the environment (with the exception of olfaction). The thalamus

filters the information depending on a person’s arousal state before forwarding the filtered information

to the cerebral cortex for further processing. The thalamus receives information from many brain

regions, including the amygdala (discussed in more detail below) and sends projections back to these

structures to create circuits involved in many different functions. The information passing through the

thalamus relates, for example, to motivation, behaviour planning and sleep regulation. The thalamus

also participates in learning and memory.

23 | 1.3 THE BRAIN

Figure 1.3.5. The thalamamus and hypothalamus by CNX OpenStax used under a CC BY 4.0 licence

The hypothalamus plays an important role in regulating the autonomic nervous system. It connects to

sites of the endocrine system that are involved in the release of hormones, including the adrenal glands,

which are critical for the release of so-called “stress hormones”. The hypothalamus is also involved in

regulating behaviours that are critical to keep us alive, including eating, drinking and temperature

control.

Basal Ganglia

The basal ganglia (BG) consist of a group of brain structures including the subthalamic nucleus, the

nucleus accumbens (sometimes called ventral striatum) and the corpus striatum, which again consists of

the caudate nucleus, the putamen and the globus pallidus. You don’t have to remember all the

substructures of the BG and their functions. You are introduced to these terms here because they may

appear in some readings relating to the neuroscience of conflict management. You can then refer back

to this chapter to make sense of any relevant readings. The BG are primarily involved in motor control

and movement but have also been found to be involved in the perception and interpretation of

emotions (Pierce & Péron, 2020) and emotional speech processing (Paulmann et al., 2011), which is why

we are mentioning the basal ganglia here. The nucleus accumbens, one of the substructures of the BG

that we mentioned above, is the region in which dopamine is released and research suggests a link

between the nucleus accumbens and positive arousal, as well as behaviours associated with that arousal

(Davidson, 2010).

1.3 THE BRAIN | 24

Limbic System

The term “limbic system” was first introduced in the middle of the 20th century by MacLean (1952) and

is still commonly used to describe several structures that are located on the inside edge of the cerebral

cortex and that are thought to play a significant role in motivation, memory and emotion.

Figure 13.6. BrainFacts.org 3D Brain allows you to move the image of the brain, looking at different

angles and different parts of the anatomy. Click on the image above to go to the section looking at the

used with permission)

There has been ongoing disagreement as to which structures exactly form part of the limbic system

(Ledoux & Phelps, 2008). Furthermore, neuroscience research has found that emotional processing

cannot be localised to the structures of the limbic system (Feldman Barrett, 2017a; Feldman Barrett,

2020; Ledoux & Phelps, 2008; Pessoa, 2017). Research has also found that some structures of the limbic

system, e.g., the hippocampus, are far more important for other cognitive processes (e.g., memory) than

for processes involved in the experience of emotions (Ledoux & Phelps, 2008). Furthermore, multiple

brain areas, of which many are not included in the limbic system, have been found to play an important

role in the perception, experience and communication of emotions (Feldman Barrett, 2017a; Feldman

Barrett, 2020; Ledoux & Phelps, 2008; Pessoa, 2017). Several contemporary neuroscientists reject both

the idea that there is an ancient, emotional centre in our brain as which the limbic system is frequently

presented in both scientific publications and popular press (and surely you would have come across

courses, books or articles that promised you to help you learn to control your emotional brain), and the

idea that emotions and cognitive processes can be clearly separated (Feldman Barrett, 2017a; Feldman

Barrett, 2020; LeDoux & Brown, 2017; Ledoux & Phelps, 2008; Lempert & Phelps, 2016).

While we acknowledge that the experience of emotions is not limited to the limbic system, we will

consider

25 | 1.3 THE BRAIN

the limbic system here as the umbrella term that typically refers to several brain structures that play an

important role in emotional experiences. Many sources include at a minimum the hippocampus,

amygdala and cingulate cortex, which we will introduce below in more detail. You may wish to watch

this short video as an introduction to these structures [1:52]:

One or more interactive elements has been excluded from this version of the text. You can view them

online here: https://oercollective.caul.edu.au/neuroscience-psychology-conflict/?p=72#oembed-4

Hippocampus

The hippocampus is located inside the temporal lobe and plays an important role in learning and

memory, especially for episodic memory and autobiographical events (note how these functions relate

much more to cognition than to emotions) (Gluck et al., 2020). The hippocampus is vulnerable to

damage caused by the experience of stress. People who are exposed to ongoing conflict may suffer

chronic stress and are thus vulnerable to hippocampus damage, which may again result in the loss of

memory.

Amygdala

The amygdala has been found to play an important role in emotional memories, identifying emotional

stimuli, including the emotional stage of other people, and physical arousal in response to certain stimuli

(Davidson, 2010; Freberg, 2019). The amygdala is particularly active when we are confronted with

danger/ thtrets and when we are in negative emotional states, but it also appears to play a role in

reward and some positive emotional states (Freberg, 2019; Ledoux & Phelps, 2008). Furthermore,

research has found that the amygdala also reacts to emotionally neutral, but unusual stimuli, which may

suggest that the amygdala processes novel, unusual stimuli, especially those that might be important to

safety and survival (Freberg, 2019; Ledoux & Phelps, 2008). We will look at the amygdala in much more

detail in Chapter 3 since this structure has been found to play an important role in the perception and

experience of emotions (as well as during “the stress response”). If you want to learn a bit more about

the amygdala as early as now, please watch this video:

One or more interactive elements has been excluded from this version of the text. You can view them

online here: https://oercollective.caul.edu.au/neuroscience-psychology-conflict/?p=72#oembed-5

1.3 THE BRAIN | 26

Cingulate Cortex

The cingulate cortex consists of the anterior cingulate cortex (ACC) and posterior cingulate cortex (PCC).

You may come across both terms in readings on neuroscience and conflict management, which is why

they are both briefly mentioned here. The ACC is involved in emotion regulation and decision-making,

while the PCC is of interest for its involvement in memory and consciousness.

Figure 1.3.7. Illustration of brain regions by National Institute of Mental Health, National Institutes of

Health is in the public domain

27 | 1.3 THE BRAIN

1.4 THE PERIPHERAL NERVOUS SYSTEM, NEUROTRANSMITTERS AND HORMONES

The Peripheral Nervous System

Our nervous system can be divided into two major parts: the central nervous system and the peripheral

nervous system (PNS). We covered the central nervous system (the brain and spinal cord), in the

previous topic, and will now turn to the PNS. The main role of the PNS is to facilitate the communication

of the body with the spinal cord and the brain. It contains two subsystems: the somatic nervous system

(SNS) and the autonomic nervous system (ANS).

Figure 1.4.1. This image by The Saylor Foundation used under a CC BY-NC-SA licence.

Please watch the following video to learn more about the nervous system [2:01]:

1.4 THE PERIPHERAL NERVOUS SYSTEM, NEUROTRANSMITTERS AND HORMONES | 28

One or more interactive elements has been excluded from this version of the text. You can view them

online here: https://oercollective.caul.edu.au/neuroscience-psychology-conflict/?p=74#oembed-1

The SNS consists of the cranial nerves and the spinal nerves and is involved in voluntary movement. The

ANS controls vital organs like the heart, lungs and the digestive system and participates in regulatory

functions like blood circulation and reflex behaviours (e.g., respiration, coughing and vomiting). The ANS

is regulated by the hypothalamus, which we described earlier in this chapter. Since the hypothalamus

gets activated when we are aroused, emotional experiences frequently involve changes in our ANS.

The ANS can be further divided into two main parts: the sympathetic and the parasympathetic nervous

system (there is a third system, the enteric nervous system, but we will not cover this system in this

eBook).

Sympathetic Nervous System

The sympathetic nervous system is of great importance to this eBook since it is involved in the

experience of stress and intense emotions. You will most likely have heard about it as the fight or flight

system. This system prepares our bodies for action when we perceive danger, threat or some other

form of emergency, like witnessing an accident unfold in front of us. When we are faced with danger or

another type of emergency, the sympathetic nervous system will kick in in various ways, including by

increasing our blood and oxygen flow to the essential body parts like the heart, lungs and large muscle

groups. At the same time, other functions like digestion and salivation are placed on standby. We will

learn more about this system in Chapter 3 when we consider the stress response in more detail.

Parasympathetic Nervous System

The parasympathetic nervous system balances the sympathetic nervous system’s actions during the

stress response. Its role is mainly to provide rest, repair, and energy storage. It is also activated by

internal stimuli like the arrival of food in the digestive system.

Methods and Digital Technologies to Measure Brain Activity

Many of the readings that discuss implications from neuroscience research for conflict management

mention methods and digital technologies that are commonly used in such research. If you don’t have a

29 | 1.4 THE PERIPHERAL NERVOUS SYSTEM, NEUROTRANSMITTERS AND HORMONES

background in medicine or neuroscience, you may not be familiar with all these methods. Therefore, we

will very briefly introduce you to the most used methods to facilitate your understanding of such

research. These methods and technologies include:

• EEG (electroencephalography)

• MEG (magnetoencephalography)

• CT (computed tomography)

• PET (Positron emission tomography)

• MRI (magnetic resonance imaging)

• fMRI (functional magnetic resonance imaging).

Figure 1.4.2. PET/MRI by Tomas Vendis used under CC BY SA 4.0 licence

1.4 THE PERIPHERAL NERVOUS SYSTEM, NEUROTRANSMITTERS AND HORMONES |