Page 12 - JCBP-3-3

Journal of Clinical and
Basic Psychosomatics Non-invasive neuromodulation for geriatric depression

attracted widespread attention. In particular, a study in a single session. Theta-burst stimulation (TBS) is a
93
adjusting rTMS frequency based on individual alpha specific stimulation pattern in rTMS that simulates theta
frequency (IAF) showed that the closer the IAF and waves in the brain and delivers rapid pulse patterns to
114
rTMS frequencies, the more significant the therapeutic induce changes in neural plasticity. TBS mainly includes
effect on MDD. Individual differences are not only two stimulation paradigms: iTBS, which has excitatory
106
exhibited by IAF but also suggest its heritability and effects, and continuous TBS, which has inhibitory effects.
stability over time. This discovery provides a scientific In clinical applications, iTBS is commonly used to treat
107
basis for personalized rTMS treatment, which is expected neurological and psychiatric disorders such as depression
to promote precision and effectiveness. Future research and anxiety, and iTBS positively affects older patients with
should focus on advancing personalized rTMS for older depression. 98,99,114 Compared with traditional rTMS (which
people with depression to enhance targeted treatment and takes 37.5 min), iTBS (approximately 3 min) has a shorter
significantly increase remission and cure rates. stimulation time and higher treatment efficiency. 115-117 In
recent years, researchers have begun to explore different
Deep transcranial magnetic stimulation (dTMS) is stimulation modes to optimize the therapeutic effect of
an innovative non-invasive neuromodulation technique dTMS. Attracting significant attention, the TBS burst mode
that has evolved from rTMS technology. This technique stands out for its rapid ability to generate substantial neural
generally uses H1 coils to stimulate the LDLPFC at regulatory effects. The application of TBS mode in dTMS
high frequencies, achieving a stimulation depth of 4 – provides new approaches to optimizing brain stimulation
5 cm. 93,96,108 It addresses the limitations of conventional therapy. 118,119 However, its safety and effectiveness in
rTMS treatments for depression in older people. Recent clinical treatment require further research to establish
empirical investigations have highlighted its substantial these findings.
efficacy in MDD in older adults. In a randomized controlled
trial using the H1 coil over a 4-week intervention period, 2.4. BLT
dTMS achieved response and remission rates of 44% BLT has garnered significant attention given its rapid
and 40%, respectively, in the treatment of MDD in older and significant neuroregulatory effects. This therapy
individuals, surpassing the outcomes observed in the is primarily implemented through the visual pathway,
sham stimulation group. A separate investigation of where intrinsic photosensitive retinal ganglion cells serve
109
depression in individuals aged ≥70 years demonstrated that as the main photoreceptors responsible for transmitting
dTMS significantly ameliorated depressive symptoms. light signals to the suprachiasmatic nucleus (SCN) of
110
In addition, a multicenter phase IV open-label study the hypothalamus. 120,121 SCN activation is one of the
documented response and remission rates of 73% after 20 key mechanisms by which BLT affects emotions, sleep
sessions, thereby reinforcing the potential efficacy of rTMS patterns, circadian rhythms, and hypothalamic–pituitary–
in treating depression among older people. Although adrenal axis activity. 122-124 Targeting SCN to regulate
111
dTMS in treating geriatric depression remains under melatonin production can positively affect patients with
investigation, current evidence indicates that it is a safe and depression, by influencing circadian rhythms, enhancing
well-tolerated therapeutic option. Continued research into mood, and improving sleep quality. 123-126 In BLT, intrinsic
the efficacy of rTMS may improve the clinical applications photosensitive retinal ganglion cells are capable of
and guidelines that more effectively assist older patients in transmitting light signals captured by the retina to the
managing depression. lateral habenular nucleus in the brain, thereby exerting
127
dTMS is a non-invasive brain stimulation technique antidepressant effects. Initially developed for treating
developed from rTMS and is capable of stimulating a wider seasonal affective disorder, BLT has since been widely
and deeper range of brain regions. The FDA has approved adopted to address non-seasonal depression, including
the use of dTMS, specifically with H1 coils, for the geriatric and chronic forms of the condition. 128
treatment of depression in older people, including those BLT can effectively regulate the circadian rhythms
with treatment-resistant depression. The eight-shaped of older adults. A 3-week randomized controlled
111
129
coil used in conventional rTMS mainly generates shallow trial, conducted with 126 older patients suffering from
cortical stimulation, with a penetration depth of induced depression, revealed that BLT significantly alleviated
current being approximately 1 – 4 cm. In contrast, the H1 symptoms of non-seasonal depression. Similarly,
130
112
coil can achieve deeper stimulation, with a depth of up to 4 Riemersma-van der Lek et al. confirmed the efficacy of BLT
– 5 cm. Compared with traditional transcranial magnetic in symptom relief and preventing further deterioration.
113
131
stimulation therapy, dTMS requires a shorter treatment Another study indicated that the therapeutic effects of
time and fewer pulses, providing better therapeutic effects BLT can persist for up to 1-month post-treatment. In
132
Volume 3 Issue 3 (2025) 6 doi: 10.36922/jcbp.5019