1. Why are we sad? Why do we commit suicide?
Psychology 320

2. Moving on… to Sadness Thought questions for today
What kinds of things make us sad?
What is the difference between sadness, grief, and depression?
Is there any evolutionary advantage to experiencing any of these?
What do we do when we are sad?
What do we feel (physiologically)?

3. Moving on… to Sadness Arguably the most negative, aversive emotion
Also referred to as “distressed”
Arises from failure or separation
What is ”failure” (or separation) if not the result of an incorrect prediction?
What are predictions if not “associations” that have been conditioned?
The sensation is so intense, that we desperately seek “negative reinforcement”
We often seek to restore things to “the way they were” before the sadness came on
“I wish I could go back”
Serves as heavily adaptive
To restore an “environmental homeostasis”
To ensure no failure
To ensure social cohesion

4. Sadness in social context
Most often, sadness is the result of failure in some social context
Most often, in a social context, saddness is associated with “grief”
Death
Break up/divorce
Argument
Grief is not just social
Grief is, essentially, the “sadness” associated with loss
Grief is so predictable, that we have 5 stages (Kubler-Ross & Kessler, 2005)
Denial
Bargaining
Anger
Depression – often the longest stage
Acceptance

5. Sadness
We could talk about sadness in gradations
Disappointed
Sad
Distraught
Heartbroken
Hopeless
Grief-stricken
As sadness continues, it gradually leads to more and more inactivity, lethargy, and eventually, withdrawal
Withdrawal can occur in all aspects of life, though social is most evident

6. Sadness And “arousal”…
Enhanced or increased neural activation
Generally speaking, arousal is a good, positive thing
Though can be negative, i.e. fear and anger
Sadness is associated with reduced arousal – which kinda makes sense…

7. Sadness “Depression” = a neural depression of activity
So, not surprising that:
If sadness = reduced arousal
And “Depression” is “depressed neural activity”
That “Depression” = pervasive sadness
Depression is often associated with “lack of motivation”
And “motivation” or “being motivated” is most always associated with a drive to act, or in essence, arousal

8. Sadness – when there’s too much…
Depression is often associated with:
Lack of motivation (arousal)
General cortical depression; systemic dysfunction; hightened HPA (and, perhaps – exhaustion)
Feeling of despair (no goals will come to fruition; no expectations will be met)
Learned helplessness – Seligman and Maier, 1967
Disruption of PFC and downstream targets (i.e. amygdala and dorsal raphe nucleus)
Probably a misnomer
Lack of desire
The pursuit of something and/or feeling of want/wish
Disruption of PFC and nucleus accumbens; amygdala
Anhedonia
The lack of desire and/or enjoyment of things pleasurable

9. Sadness and the Brain
Sadness associated with a disruption in predictive power of associations
PFC are especially lowly active

10. Sadness and the Brain
Depression is associated with decreased cortical volume (thus grey matter) of the:
PFC
Cingulate Cortex
Hippocampus
Depression is associated with decreased connectivity (thus white matter) of:
PFC-dependent, top-down inhibitory control of emotion
Reward pathway (mesolimbic pathway)
Depression is associated with:
Increased activity in the amygdala
Dysfunction of the “Dorsal Raphe Nuclei”
A brainstem region that is responsible for making and projecting serotonin

11. The Brain and Suicide
Recall again what we have going on in cases of depression (but also PTSD, Bipolar, and as we’ll see in a coming lecture, drug abuse and alcoholism):
Decreased PFC control
Increased Amygdala
So what does that mean?
Decreased logic and reason; Decreased ability to effectively predict causality; Decreased inhibition of amygdala
More fear; More irrationality; More “Act now, Think later”
Taken together – More Impulsivity

12. The Brain and Suicide So what is “impulsivity”
So what do we know about suicide?
10th leading cause of death worldwide
Approximately 43,000 deaths in US in 2014
Approximately million attempts per year worldwide
3 of 4 deaths are male but 4 of 5 attempts are female
In US, it is most often attempted by adolescents

13. The Brain and Suicide So what do we know about suicide?
Most describe feeling “despair”, “hopeless”, “sad”, “depressed”, “alone”, etc.
Approximately 2/3 of suicide victims are clinically depressed
But how can we truly trust this statistic isn’t higher?
Brains of suicide victims have decreased serotonin
Brains of suicide victims have increased GABA
Suicidality corresponds with structural abnormalities of PFC and PFC dysfunction including deficits in executive function
Behavioral inhibition
Spatial working memory
Visuospatial conceptualization
Visual attention
Increased impulsivity
Increased amygdala size (though equivocal – that is to say, the research is back and forth on this)
Probably not causal but merely correlational

14. The Brain and Suicide
Recall that more young people attempt suicide in US
Increased stress on youth?
Increased attention on suicide?
Increased access to methods?
Increased pressure from peers?
Decreased PFC function!!!!
Irrespective of sadness/depression/suicide risk – the PFC is not fully “online”, not fully developed until around age 25.
Adolescents are behind the 8 ball already, let alone when their stress levels and/or depression start negatively influencing PFC activity.
Males tend to be more impulsive than females
Perhaps why males are “successful” more often – perhaps due to method

15. Well… this is depressing
So what can we do to help this?
Given what we know about depression, at-risk youth, and the brain… what kinds of things can we do to minimize the risk of suicide?
In adolescents?
In adults?
Consider “learned helplessness hopefulness”
Hypothetically – what could we do to manipulate the brain (at a reductionistic level) to overcome depression, sadness, and/or suicide?