Understanding Depression

Depression

• Depressed Individuals often struggle with processing written or spoken information.
• Conversations may be a challenge for depressed individuals, characterized by slow speech, long pauses, limited vocabulary, and a monotonous tone.
• Some depressed individuals may prefer solitude and silence, while others exhibit agitation, restlessness, pacing, hand-wringing, excessive sighing, moaning, and complaining.
• Problem-solving becomes difficult for those experiencing depression, as they struggle to generate solutions.
• Depression often brings a heavy feeling to each moment, accompanied by internal self-recriminations.
• Depressed individuals may neglect personal hygiene and appearance, frequently reporting somatic symptoms lacking an apparent physical basis.
• Feelings of utter dejection, hopelessness, and lack of initiative are commonplace, often accompanied by apprehension, anxiety, and despondency.
• Depression in children can manifest as somatic complaints such as headaches or stomachaches.
• Older adults with depression often exhibit distractibility and memory loss.
• Cultural variations may influence the symptoms of depression, potentially stemming from differing standards of acceptable behaviour.

Mania

• An individual in the throes of a manic episode typically:

• Speaks loudly and incessantly, often incorporating puns, jokes, rhyming, and interjections.

• Exhibits a rapid shift in topics during conversations.

• Displays an increased need for activity, leading to excessive sociability, intrusive behaviour, and a tendency to be constantly busy.

• May be oblivious to the potential pitfalls of their actions.

• Becomes quickly angered or enraged when attempts are made to curb their momentum.

• Experiences sudden onset of manic symptoms over a day or two.

• Manic episodes can last from several days to several months.

• The diagnostic criteria for Bipolar disorder are a "bridge" between schizophrenia spectrum disorders and depressive disorders, reflecting similarities in symptomatology, family history, and genetics.

Prevalence of Major Depressive Disorder (MDD)

• The lifetime prevalence of MDD exceeds 20%, potentially reaching as high as 50%.
• The broad spectrum of severity suggests that not all individuals meeting DSM-IV criteria for MDD require intensive treatment.
• A 2012 Canadian Community Health Survey (CCHS) found that 3.9% of participants met criteria for MDD in the past year.
• Approximately two-thirds of those with past-year MDD sought treatment, and about one-third used antidepressant medication.
• Prevalence of MDD is higher in women and younger age groups.
• MDD is roughly twice as common in women compared to men, a gender difference observed across numerous countries and ethnic groups.

Understanding Gender Differences in Depression Prevalence

• Understanding the cause and timing of the gender disparity in depression prevalence may provide insights into the etiology of the disorder.

Persistent Depressive Disorder

• DSM-5 includes a category for persistent depressive disorder, encompassing chronic depression and dysthymia.
• A large Australian study (Murphy & Byrne, 2012) found that persistent depressive disorder is a prevalent condition.

Biological Theories of Mood Disorders

• Research supports the theory that mood disorders have a biological basis.
• These biological theories do not negate the relevance of psychological perspectives.
• Both biological and psychological perspectives may describe the same phenomena, but using different terms, such as learned helplessness vs. low serotonin.
• These perspectives are considered complementary rather than incompatible.

A Developmental Model of Depression (Beck, 2008)

• Research comparing the cognitive model of depression with neurophysiological studies suggests a possible link between cognitive processes and biological mechanisms in depression.
• The cognitive model proposes that anomalous genes, cognitive biases, activation of the hypothalamic-pituitary-adrenal (HPA) axis, and dominance of limbic activity over prefrontal function can lead to depressive symptoms.

Key Biological Factors in Depression

• Genetic diathesis
• Low serotonin or norepinephrine levels in depressed phase
• High norepinephrine levels in manic phase
• Activation of the HPA axis
• Dominance of limbic activity over prefrontal function
• Deficient reappraisal of negative cognitions

Major Biological Theories of Mood Disorders

• Genetic predisposition
• Neurotransmitter imbalances (e.g., serotonin, dopamine, norepinephrine)
• Structural and functional brain abnormalities
• Neuroendocrine dysregulation
• Inflammation